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Home > Read > Work > How Creches At Indian Offices Can Empower More Women To Work
How Creches At Indian Offices Can Empower More Women To Work
Women can't have it all precisely because they are responsible for too many things! Would creches at Indian offices help to level the playing field for women?
The recent confessions by Indira Nooyi on why "women can't have it all" started a different kind of debate with a lot of women around me. A lot of the debate material revolved around lack of support structures for women to pursue their jobs with greater efficiency. I heard a lot of statements, all signifying the lack of support structures.
"You need a support structure. You have to work outside for money and also because you want to." "Lack of support to fulfill the multiple roles that have fallen in our arms make us helpless."
Women make up 24% of India's workforce. But only 5% of them reach the top layer, compared to the global average of 20%. A majority of them give up their jobs or fall behind on performance during their 'start a family' period in life. When we think of the reasons for this imbalance, one major point seen is the sheer absence of day-care at the workplace keeping millions of working women from working. Indian work places and environments force women to choose between work and children, instead of adapting itself to the changing roles of women in our society.
She has to take the harsh decision of choosing between what she wants more and what is expected out of her.
Over the years the concept has been this: if the mother works, the grandparents take care of the child. While the mother is expected to take jobs like teaching or banking, her exploring and being outgoing to take up challenging tasks and high profile jobs is looked down upon. She has to take the harsh decision of choosing between what she wants more and what is expected out of her.
It is not that she lacks efficiency but the dual burden makes it difficult for her to handle both, thus defining the why she "can't have it all". This "all" is always defined in a way that makes it difficult for us to differentiate between her needs and her desires, her expected roles and her capabilities. Often this leads to us saying, "women can't work hard", "they take too many leaves", "they can't give in extra hours". Saying all this, we ignore the root of the problem and on the surface, think that the solution is to not employ women at all.
"Who doesn't want to give efficiency? But with dual burden of children and work, we just fall flat. Our society thinks its only mothers job to take care of the children. But now that we work, do we get enough support from our environment? No."
Gender needs is a very broad term to look at here. With the changing social and global roles, the practical and strategic gender needs have evolved too. What can be done to make them more efficient? Maternal leave? Crèche facilities at work place? What is it that can be provided from thegovernment or organizations that make them more at ease?
A Practical Gender Need (PGN) would be to have a crèche available in the vicinity/workplace, a long term impact-creating Strategic Gender Need (SGN) would be to create a Bill that promotes the women's participation in decision making acknowledging the changing gender relations and roles of men and women in the society.
Creches: Facilitating functioning at multiple levels
In India, nuclear families are growing, with the middle class growing dramatically, especially in urban areas. The traditional concept of joint families has shifted and so the need for caregivers and caretakers of the children has taken a turn too. The old idea of grandparents taking care of children is changing and there is a strong need to create spaces of support for these couples and most importantly, the women looking to balance work and family.
After all, the modern Indian family has the woman donning multiple roles of wife, mother and business executive. Each of these roles demands her very best. And because of her changing role, there is an increasing need for a support system other than family to help balance home and work. No longer is it a social stigma if the woman looks at child-care options to look after her child while she works. This is indicated by the growing number of daycare centres, nurseries and pre-schools in India's largest cities.
And it is not just the women who will benefit for the crèches in establishments as they move away from the stereotypes related to working of women. Companies will become more employee-friendly, improve their image along with the reduced attrition of working parents. The financial stress on parents will be reduced as both participate in childcare. A child will remain close to parents during early childhood and the grandparents will find time for themselves, and the freedom to pursue hobbies.
" I left my job because I had to start a family and none of the work places gave me the space to take care of my child alongside. It is expected from the mother to leave her job."
"My friend is delaying having a baby because she knows that once that happens, she will be stuck between the two – family and work. Obviously, she will have to give up work."
The history of legislation on creches in India
In the case of Indian women who are still struggling to find a space in the decision making of this country and their own homes, having a bill that makes it mandatory to have certain rights given to her at the work place will only make her task much more efficient and hasten development of family and work spaces too.
It is not that such a bill hasn't been thought of ever. We have had systems that have tried to create such a support structure through government interventions. One of this has been the Rajiv Gandhi National Crèche Scheme for Children of Working Mothers currently covering tribal, rural and urban children across 449 districts. And in 2013, the Ministry of Women and Child Development passed a resolution (No. 16-1/2012-CW-I) to "provide and promote crèche and day care facilities for children of working mothers, mothers belonging to poor families, ailing mothers and single parents."
While this is laudable, if a crèche facility is mandatory for factories, plantations and beedi and cigarette workers, what is stopping the government from making it mandatory for private companies?
In 2006, a draft bill on Crèches in Establishments was proposed but was stalled without any reason with no document available till date. The Country's National Policy for Children talks about providing and promoting crèche and day care facilities for children of working mothers, mothers belonging to poor families, ailing mothers.
A Working group on Development of Children in the XIth Five Year Plan also looked at expanding the National Creche Scheme for children of working mothers so as to increase the number of crèches for children from 30,000 to 100,000 by 2012 and also support single parents. Though there has been a frequent mention on development of new legislation for crèches and day care services for children, a concrete step is still not taken.
How can we promote more creches at work?
There are a few organizations that are committed to campaigning in India for the rights of survival, development and protection among poor and underprivileged 0-to-6-year-olds like the Forum of Creche and Childhood Services. But there is a strong need that we take this to a higher level of including establishments like the multinationals and other corporate firms with women employees to include such structures as a mandate in their companies.
It is time we as women working and facing such issues and including our male counterparts take this issue forward. Its time we advocate the reopening and drafting of a Bill for 'Crèches in Establishments'.
During these discussions, I came to know about a campaign that has been started at the Greenpeace website in this regard which points out the need to make crèches at workplace a rule. While it's a story of how a woman left her job for her daughter, it is the story of many of us. We always talk about issues, here is how we participate and advocate in action mode!
Go ahead. Sign the petition for the benefit of many.
She says, 'women can't have it all'. I say, let's facilitate them towards the direction of having what they can completely, with efficiency.
Pic credit: opensource.com (Used under a cc license)
Suchi Gaur
A Development Communication & Social Work professional working in the field of gender, health and technology
Bindu (@hope_a_holic) -	July 25, 2014 at 11:03 am
Thanks for citing my petition. Wonderful article and well researched! A mother CAN continue working without worrying about her child's safety! This is possible if creches at all workplaces become compulsory. In 2013, the Ministry of Women and Child Development passed a resolution (No. 16-1/2012-CW-I) to "provide and promote crèche and day care facilities for children of working mothers, mothers belonging to poor families, ailing mothers and single parents.
Let's make this happen! Please help me get support for my campaign by sharing this link as widely as you can! http://www.greenpeacex.in/petitions/make-creches-at-workplaces-a-rule-not-an-exception?bucket=ww
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Syntax is a royal pain in the neck for beginning programmers. For a lot of kids learning computing or programming syntax is the single largest hurtle. It's hard to teach both a new (programming) language and a new way of thinking and problem solving at the same time. This tends to be a big stumbling block for teaching a lot of basic computing concepts. For years there have been tools developed that remove syntax from the equation. Alice and Scratch are probably the most well-known and popular of these tools. But there are other options and I find that many people don't know about them all. I'm not sure I know them all but I do know something about a bunch of them. I thought it might be useful to list the ones I know about to help others find what might work for them. Feel free to tell me about any I am missing BTW. I'm always looking for new things to try.
All of these tools have some great features and either university or private research behind the development. Curriculum for them can be found through their web sites or Internet searching. Textbooks exist for some of them as well. They're listed in no particular order so check out something new to you.
GP is a free, general-purpose blocks programming language (similar to MIT's Scratch) that is powerful yet easy to learn. It runs on most platforms, including laptops, Chromebooks, tablets, and web browsers. This one looks particularly interesting as the GP stands for General Purpose.
Alice Alice is a 3-d environment from Carnegie Mellon. It is probably the most popular and best known of all of these tools as CMU has been promoting it for some years. It can be a bit resource intensive but the ability to create 3D worlds is a big plus. The latest version, Alice 3.0, allows users to export to Java programs. This makes Alice very popular with APCS teachers.
Kodu is a coding environment originally developed by Microsoft Research for the Xbox 360 but now also available for Windows PCs. It is highly graphical with a simple When/Do model of programming. Designed for younger students (8 is the target age) it is very usable by precocious younger students and powerful enough for older students.
Scratch Scratch was developed at MIT at the Lifelong Kindergarten Research Group. This 2D platform is less resource intensive than Alice and Kodu. The Scratch web site with its sharing and social abilities really adds to the value of the Scratch platform.
Scratch Jr is a version of Scratch for even younger children.
Snap! (formerly BYOB – Build Your Own Blocks) Snap! nee BYOB is an expansion of Scratch that has been developed at the University of California at Berkeley. It adds new blocks and OOP features. It's being used by a number of AP CS Principles pilots. Snap 4.0 is currently in early beta but the cool thing about it for many schools is that it is completely web browser based so no software installation.
App Inventor for Android Think about App Inventor as being Scratch for developing Android phone apps and you get the basic idea. While not strictly Scratch is was developed by people from both Google and MIT. It resides at MIT these days and is being developed there using ideas from Scratch, Blockly and other sources as a teaching language. For students (and their teachers) who want to get into phone apps it is about the easiest tool there is. It is mostly web based as well.
Thunkable - Thunkable supports Android and they are working on iOS support. Thunkable is based on MIT App Inventor.
Tickle is a fairly new product (Released: Mar 24, 2015 on iTunes) on the Scratch model. "Tickle is the world's first app that enables anyone to program an air drone. You can now program the Sphero robotic ball, Parrot mini quad copter, and Philips Hue lighting system, all wirelessly right from your iPad." I don't own any of the supported devices to try it out. Let me know if you do and what you think of it.
CodeWise A card game and an application. Designed to help very young students start programming.
"By using the CodeWise card game pupils can learn how to 'program' each other. You can find an assignment on each card such as: sing a song, jump, stand up/sit down or move forward.
Groups of pupils can create a programming code together in a fun and interactive way by placing the cards in a certain sequence. The code can be checked by a different group. The game can also be conducted by two pupils."
AgentCubes online is the first of its kind 3D online programming environment and was developed by the people who created AgentSheets.
Hopscotch is another iPad app from the same people who created Daisy the Dinosaur. It's a lot like a very basic Scratch and pretty limited as of this review (Hopscotch–Visual Programming for iPads). But it does run on an iPad and that makes it accessible to a lot of people.
Stencyl borrows heavily from Scratch but is focused on creating games. Games may be created and published for iOS, Android, HTML5, Windows and Mac according to the web site.
Move the Turtle (available for iPhone/iPad, $2.99): From what I read this is a lot like Daisy the Dinosaur. The object of Move the Turtle is to use commands to move the turtle though a series of puzzles.
PocketCode allows you to create your own games, animations, interactive music videos, and many kind of other apps, directly on your Android phone or tablet.
RoboMind RoboMind is software specifically developed to support technology education. By programming a robot, students learn about logic, computer science and robotics.
Waterbear Waterbear is a toolkit for making programming more accessible and fun. Having a visual language means you don't have to focus on learning a syntax to start programming.
Actimator is web based and games can be played on Android and iOS devices.
I have never met a student who cut their teeth in any of these languages and did not come away profoundly damaged and unable to cope.
You would do well to read some Dijkstra.
I mean this reads to me very similarly to teaching someone to be a carpenter by starting them off with plastic toy tools and telling them to go sculpt sand on the beach.
Not one thing they learn will bear any piece of resemblance to real work. All you're doing is teaching them misimpressions of what the job is, and tricking them out of having meaningful formative experiences.
This is 101 never-do-this material to anyone with actual training as a teacher.
I take it that John Haugeland is of the 'everybody can learn to be a computer programmer and therefore everyone should learn how to write code' school?
These are not proper programming languages, anyone with half a brain knows that, but why deny those who can't or don't want to 'code' the opportunity of being creative with these tools and learning some logic skills along the way. Not everyone wants to be a computer programmer but a lot of kids like to create their own game or 'app' for fun.
These are all great tools. I have used Scratch, Alice, and Kodu in primary, secondary schools, and colleges with a lot of success.
@John – can you confirm the scope of the research you cite or this just anecdotal evidence? Because most of the literature I have read indicates a very positive trend.
BTW I have no idea what this means "This is 101 never-do-this material to anyone with actual training as a teacher." Can anyone understand what John is trying to say here?
John, ouch. I am not quite sure what you mean by real work. A 5th grader is not going to do much commercial programming but they sure could have some fun learning to problem solve with these languages. Give the average 5th grader Java or C++ and see what their opinion of programming is after a week. My sophomore Programming I kids that may take only one programming course in their life can learn some problem solving, procedural thinking, the basics of coding language (If, Repeat, etc) and have a little fun writing stupid little games. They usually get an idea of what programming can do if they learn a big kid language. A good carpenter that is an artist with wood probably started with plastic toys on the beach when they were kids. It is possible to have some serious fun with all these languages and stimulate a kid's curiosity to go further. All of these languages need to be on a beginning programming teacher's must learn list.
My son is 12 and he's been doing Small Basic for years now and we will start with a higher typed language like C in language soon and he has had NO problem with syntax at all or progression to a C based language. He started with a visual based interface like the tools used in FIRST Lego League Robotics and moved forward to more advanced languages as his knowledge grew mathematically and logically. The key is for the foundation and the interest to be laid first with these types of tools that are TARGETED for the right age group. Who would foolishly think a 5 year old with NO Algebra, Calculus, Discrete Math (etc) experience would start right the gate writing Lambda functions with C++. Utter foolishness to think that we start them out with an higher end language without the background needed for mastery. ...was the comment posted as a joke?
These tools are all great, if you see syntax as a major obstacle to programming and/or computer science.
However, I don't think semicolons and curly braces are what's holding us back.
I completely agree with Alfred and completely disagree with John.
I am a trained and experienced teacher and have found that using these tools is an excellent introduction to programming. Using them, young children can focus on important concepts and problem-solving and less on finding syntax errors.
There have in fact been studies done on these programs' efficacy, and they are positive. This is one such study I have found.
Sure, there are young children (such as Anonymous' son) who can take to pure coding languages easily. And there is certainly reason to argue for using proper coding languages with older (High School) students. However, with elementary or middle school students it is perfectly reasonable to use simpler tools.
Take the frustrations away and allow the students to experience the joy of creation. When they're ready to move on, they can take the concepts of loops, threads, conditionals, variables, etc. and start learning where to put the curly braces and semicolons.
For those who prefer the purity of code but still want an easier interface for the students to grasp, check out Greenfoot.
Greenfoot is a simple introduction to Java. It's not blocks, but there's a simple GUI that lets you manage some of the aspects of the program.
It's also worth pointing out that the new version (3) of Alice aims at being a good transition to Java, including a NetBeans plugin.
You forgot the parent of these which is around since the late 90s and still more versatile than any of its descendants: Squeak Etoys. This year the new 5.0 version was released.
Squeek eToys! Yes I knew I was forgetting something important but for some reason that slipped my mind. I will update the post. Thanks!
Emmanuel you are right that these are only the "solution" if you identify syntax as the major problem. There are other suggestions and I know you teach one of them with great success. Want to do a guest post on that?
Alfred, I teach using App Inventor in a Grade 10 course (intro) and using Python in a Grade 11 course (intro). Some of my students in Grade 11 have taken my Grade 10 course and I can state that they are not "damaged goods". I feel that they have a distinct advantage in experience multiple programming paradigms. The students that follow on to the second course are now able to appreciate the power of Java and O-O design also.
Keep up the great discussions.
Personally, I have no problem with people learning these tools, but I would *really* like to hear more from Mr. Schanzer, and applaud Mr. Thompson's suggestion that he write a guest post here on the topic.
Some of us in physics use VPython, which is the Python language with the Visual extension. http://www.vpython.org/ It's a great way to use programming as an extension and learning tool in physics as students have to create and modify the representations of physics in the 3d world they create.
As a classroom teacher who taught novice high school freshman to sort lists and do recursive math, I would disagree loudly with John. I had students take the concept of recursion and graphic flood fill and apply it into java to solve a problem that while it was easier to solve in other ways, was a perfect solution. I know that I have students who learned with both BYOB and/or Alice who are making Dean's honor roll in CS programs in several major Texas universities.
I kind of think John has not seen the power especially of BYOB/Snap where recursion, searches, sorts, etc are possible while letting the kids focus on the algorithm. Once a kid understands how recursion flood filled a square graphic, converting the algorithm to language is much simpler.
Sorry John but not every kid can focus on the algorithm when a semicolon error frustrates them way too much before the first successful code execution. I challenge any master teacher to take novice freshman female programmers, force them to learn any text based language, have them writing their own recursive sorts in under 4 six week class terms.
Did I mention the best 3 programmers in the room were two freshman female cheerleaders and a girl who was the mascot.
14 years old and writing and understanding recursion.
I am no expert - just a high school CS teacher with 19 years of battling syntax induced anxiety/failure with students.
Move the turtle is a lot more complex that Daisy the dinosaur.
Daisy has a very simple set of control structure and preset moves.
The turtle has a set structure of activities that can build a skill set and understanding, you can create and save your own functions (sub routines) then use them again..
Its great for students Y3-Y6.
Then Id suggest a move to scratch..
Thanks for the other options in the list..
A lot of people are good in programming and they do good things for it. But with all these a lot of people do not like Programming and they just simply work on the things they can do best. Your post has different ideas that we can learn and apply at the time when we require these types of stuff for the learning purpose.
I think Pocketcode from Catrobatqualifies as a nice addition to this list.
Developed by Wolfgang Slany and his team from Graz University of Technology it brings coding with block to mobile devices. There are special blocks to use the sensors of the device and he result is immediately playable on the device.
If you could only download one app it should be this one :-) All the other apps left as exercise!
Old and tired said..."Teaching logic is no bad thing however it is done. Teach them to stop, think, plan, implement and test." It's a tremendous change of attitude I see in 3rd grade class as the children work with Scratch and Wedo. They also learn to learn from each other instead of being dependent on the teacher for everything.
"A common response to my [Victor's] work is 'experts don't need that'. Galileo didn't 'need' algebra either. Just 30 yrs to do something trivial today."
Just as many classrooms today are nearly the same as their counterparts from 50-100 years ago, programming today hasn't moved in a major way since before...well, Dijkstra. It would be hard to argue that we've found the optimum solution in either case. We see a similar argument in math class, we we say using tools like Wolfram Alpha to solve equations is not "real math" - that "real" mathematics is done with pencil and paper and maybe a TI calculator. Nonsense.
As a professional software developer for 30 years, it saddens me to see a mentality - that one needs to use text-based languages to be a "real" programmer - that is mainly about being exclusionary. Yes, text-based languages prevail now, but it's not because they are the be-all end-all solution to the problem of expressing computational thinking.
Now.. think of every step forward we have seen in the last 45 years.... many of them.
Think of the various generations of languages in business. Each one has taken us a little further away from the binary bits..closer to human visual language.
I am now retired from teaching at a community college and am focusing of helping the youth of america to become creators rather than consumers.
Blockly is great! not just for kids. It empowers everyone, every age to use the "universal machine" - a computer -- to solve their very own problems.!
Once I got Hal Abelson's kitty to meow, I was hooked! And the Google Intern got us to complete the program in less than 1/2 hour!
It is fun, engaging and the very intuitive.
We are beyond the point where CS can look down our noses at those who do not excell in Calculus.
Computer Science is the cortex of STEM. -- every scientist, technologist, engineer and mathmatician needs to use programming to solve their problems in the future.
Alfred, thank you for your wonderful posts that bring so many comments!
I, too, learned programming with punch card. I carried giant tape reels on airplanes to update banking clients, and had to go down to the cubbies in the basement of our office to pick up printouts after our jobs were runt.
But I digress...today I had the opportunity to work with block coding for the first time with a class of 2nd graders and a class of 3rd graders. It was amazing to see kids learning to think creatively. Teachers were surprised at which students progressed quickly. And most importantly, an hour of code wasn't enough for them...they wanted to bring their lunches in and stay after school.
I imagine that the third grader who practices problem solving and logical thinking skills now will be the one choosing to study and learn syntax and nuances of various languages because they have seen what can be done. Once they've moved the turtle they want to create their own.
If I have the opportunity to work with more elementary students perhaps you secondary teachers will find students eager and receptive to 'real' programming.
I teach programming to kids in primary schools in the UK. We use Scratch Jr and then move onto Scratch in KS2 (K2). We also use Kodu (more as a lunchtime club) and the children progress onto Raspberry Pi programming on Python.
Programming re-imagined for the connected world.
I am a Teacher of Computing in the UK. I have programmed for 30 years; I have only taught for 6. I am one of the generation of programmers Dijkstra suggested would be damaged in exactly the same way because they were taught unstructured BASIC first. The first time I saw Pascal (my second high-level language) I took to it like a ten year old to Oreo cookies. I have never looked back or used a GOTO since.
Teaching my Year 9 Computing GCSE students structured BBC Basic today I realised something quite startling.
So, for my tuppence-worth, I believe the reason that the likes of Scratch are rightly hugely successful is precisely because the tools work closer to the way many children (visual, creative, constructivist lego buiilders!) and adults think, whatever languages they become proficient in. A good toolmaker makes tools that fit the hands and minds of the craftsman doing the creative work. Otherwise, why aren't we all coding in hand-crafted machine-code? Or Z notation?
I am 72 and have seen a lot of programming languages since the Hollerith machines.
All the negative comments I can only (-sorry guys-) see as Blah Blah.
If we follow the code geeks we would write our applications still in Assembler or even worse in RPGII.
Every smart programmer has in his own toolbox lots of fuctions and procedures he can call on and rely on. And it was Bill Gates who said "good programming is smart copying"
We have all written or copied thousand lines of codes over and over again.
Nowadays there are lots of tools for smart database programming without a line of code.
And you see the same trend for roboting computing.
And the real nerds among us like Garth should concentrate on developing smart visual blocks which applications programmers can use and make a lot of money by doing so. And yes Garth for that you need C++. And keep in mind Garth not every good soccer player needs to be a Messi, Maradonna or Cruyff.
This is definitely a great resource!
As a programmer myself what I like about Scratch, is that it is good representation of modern Integrated development Environment (IDE) approach to programming. It has drag and drop type display window but it also has script, run and break functions and libraries of resources.
My daughter (aged 10) has started using it at home lately and I find myself giving her tips such as moving her sprite back to its start position at the top of the code: I know that might be redundant but it makes fixing what she is doing easier if she always starts off at the same place. She likes it because she likes her art and its an easy way for her to create simple animations.
So I would say give it a go and see what you can do.
As ones who know the field, what are your thoughts on the viability of creating an extra-curricular environment to 'play' with these tools à la a karate class or Kumon? Too niche? Would parents see the value? Be willing to pay? Thoughts?
Jeffrey there are programs like that around the country. I don't know how much (or if they charge).
Where is Logo? Even older than Squeak (I think), and a great introduction that stresses functional programming and recursion, capable of generating fascinating graphics, but also capable of doing so much more (multiple programming paradigms (imperative, object oriented, functional, metaprogramming). It is in the LISP/Scheme family and a great introduction to either of those languages, as well as others from that family, such as Racket and Clojure.


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Michel Thomas Beginner Italian Lesson 5
Geschrieben von: Michel Thomas
Gesprochen von: Michel Thomas
Serie: Michel Thomas Beginner Italian, Titel 5
Kategorien: Bildung & Lernen, Sprachen lernen
What is the Michel Thomas Method?
The Michel Thomas Method teaches everyday conversational language that will allow you to communicate in a wide variety of situations, empowered by the ability to create your own sentences and use the language instinctively, having absorbed the vocabulary and grammatical structures. These all-audio courses were perfected over 25 years by gifted linguist and teacher Michel Thomas, and provide an accelerated method for language learning that is truly revolutionary.
Lessons 1-7, the beginner course: This course makes no assumption of knowledge of any language other than English and gives the beginner practical and functional use of the spoken language. It is also appropriate for anyone who has studied Italian before, but has forgotten much of it or does not have confidence in speaking. The Beginner course is designed to take you from complete beginner to intermediate level.
Lessons 8-11, the Intermediate course: This course is for those with an intermediate-level foundation in Italian, or those who have completed lessons 1-7 and want to take their learning to an advanced level and speak Italian proficiently and easily.
Unlike most language courses that focus around topics or grammar forms, the Michel Thomas Method works by breaking a language down into its component parts, enabling you to reconstruct the language yourself - to form your own sentences, to say what you want, when you want. Within the first 10 minutes of the course, you will be generating complete sentences on your own. It is important that you complete the lessons in order. The Method is successful because it builds on the language you learn in each lesson and "recycles" language taught in earlier lessons, allowing you to build ever-more complicated sentences. Because the Method is based on understanding, not memorisation, there is no set limit to the length of time that you should study each lesson. Once you feel you have a good grasp of the language taught in one lesson, you can move on to the next.
In lesson 5 of the Italian Beginner course, you'll learn how to talk about the past with the following:
Use of "could" ("'was able" and "would be able")
Future tense and conditional of the "handles"
Time expressions: "yesterday", "next time", "once", "twice", "soon", "all day long"
Verbs: "to owe", "to think/plan", "to hope", "to feel like" ("to have the want"), "to need" ("to have the need")
Handles: "should", "ought to"
Words ending in -ty, -al: "university", "normal"
Nouns followed by verbs: "time to do it", "opportunity to see it"
Pronoun: "everything"
Past tense (straight line in the past): "I could" ("I was able"), "I had to", "I wanted", "I had", "I/it was"
Past tense ("diving" into a point in the past): "I ate/I have eaten"
"Diving towers" ("to have" and "to be") and "diving forms" ("eaten", "gone", "done", etc.): "he told me", "I went" etc.
In the next lesson you'll be able to use reflexive verbs and more past tenses and talk about getting things done.
©2013 Michel Thomas (P)2013 Hodder & Stoughton
Michel Thomas Beginner French Lesson 4
Das sagen andere Hörer zu Michel Thomas Beginner Italian Lesson 5
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redpajama_set_name: RedPajamaCommonCrawl


Family run hotel situated on the Palmira Beach in Peguera next to the sea.
Hotel by the beach in Can Picafort.
Hotel located in the centre of Cala Rajada, near the beach of Cala Agulla.
Hotel located 300 metres from the beach in Cala Rajada.
Hotel by the beach in Ciutat Jardí (Palma).


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Moors murderer Ian Brady dies aged 79
Sadistic killer died in Ashworth Hospital this evening
Moors Murderer Ian Brady (Image: Handout/PA Wire)
Moors murderer Ian Brady had died, Ashworth Hospital has confirmed.
The 79-year-old child killer had been held at Ashworth for more than 30 years.
More recently he started a legal bid to get himself transferred to a mainstream prison, it was reported, so he could starve himself to death - he is currently force fed since going on hunger strike.
However, it is understood his condition has now deteriorated to the point he is being cared for by staff who help terminally ill patients.
Brady and Myra Hindley, who died in prison in 2002, tortured and murdered five children in the 1960s.
Former Formby Times journalist went Ian Fowler went on to become the first person to link the deaths in the Moors Murders case
Tributes paid to former Formby journalist who linked the Moors Murders
Ian wrote a feature on the disappearances of Pauline Reade, 16, John Kilbride, 12, Lesley Anne Downey, 10, and Keith Bennett, 12, which was published on February 19, 1965 – eight months before Ian Brady and Myra Hindley claimed their last victim, 17-year-old Edward Evans, and precipitated their arrest.
Mr Fowler looked at the pattern and concluded that they must be linked. He used the article to call for the setting up of a central missing persons bureau.
He went on to cover the first court appearance of Brady at Hyde magistrates and later corresponded with Hindley in prison and visited her several times with his wife Patricia Roberts, also a M.E.N. journalist, for a series of features.
Brady was jailed for three murders in 1966 and has been at Ashworth since 1985.
Jeremy Corbyn is coming to Southport
Shoplifter banned from town centre
200 homes to be built in Burscough
Drunken yob jailed for unprovoked attack
SouthportMemories of the famous Southport to Preston rail link, 50 years after it closedSteve Craddock looks back at the lost vital rail line
BurscoughJoin Martin Mere on their Evening Bat WalksThe latest news from the Wildfowl & Wetlands Trust


Promote solutions to maintain and improve our standard of living. We need to make sure the American economy is self-sustaining in order to support its people and resilient and flexible enough to meet the many challenges of the future.
The key to a prosperous economy is open and competitive markets that reward innovation, creativity and value and operate in an open, transparent and honest manner under the rule of law.
Live within our means, as a nation.
Adopt user fees where possible.


Singapore's Transport Minister Khaw Boon Wan has issued a stern warning against Malaysian vessels allegedly encroaching the territorial waters of Singapore, and declared that the Republic will not hesitate to take "firm actions" against further intrusions.
In a statement on Thursday (6 Dec), Mr Khaw added that in response to the "provocative action on the part of Malaysia", Singapore will be extending port limits "within Singapore Territorial Waters" under the Maritime and Port Authority of Singapore (Port Limits) (Amendment) Notification 2018 with immediate effect.
He elaborated that the extension "tracks the eastern boundary of the 1999 Johor Bahru Port Limits".
Mr Khaw also claimed that there have been "14 intrusions" by Malaysian vessels into Singapore's maritime boundaries, with three vessels still present in Singapore as of Wednesday (5 Dec).
"Singapore had protested the repeated intrusions via three TPNs [Third Person Notes]", said the minister, and highlighted that Singapore has urged Malaysia to "cease their intrusions and return to the status quo before 25 Oct 2018".
"Our security agencies will continue to patrol the area, and respond to unauthorised activities on the ground. They have so far responded with restraint against aggressive actions by the Malaysian Government vessels," said Mr Khaw.
Previously on 25 Oct, Malaysia had issued a government gazette announcing the extension of Johor Bahru's port limits, which Singapore claims has encroached into Singapore's territorial waters off Tuas.
"As such, the government of Malaysia refutes the view that Malaysia's government vessels had intruded into Singapore territorial waters off Tuas," Wisma Putra said.
Mr Khaw disputed the Malaysian government's claim, stating: "In 1979, when Malaysia published its map, it did not consult Singapore before drawing its territorial claim line. In fact, in 1979 no reclamation at Tuas had taken place.
"So the Malaysian unilateral territorial claim of 1979 (which we do not recognise) could not possibly have taken into account any reclamation by Singapore," stressed Mr Khaw.
Bloomberg reported Mr Loke as saying on Wednesday (5 Dec) that Malaysia's deployment of its government enforcement agencies such as the Malaysian Maritime Enforcement Agency and the Marine Department of Malaysia has not violated international law, and has not resulted in intrusion of Singapore's waters.
Consequently, Mr Loke reminded Singapore's maritime enforcement agencies to cease intruding into Malaysia's waters.
"These actions by Singapore amount to serious violations of Malaysia's sovereignty and international law, and are unconducive to good bilateral relations," said Mr Loke, adding that such intrusions "cause confusion for the international shipping community, and lead to increased navigational and safety risks to all parties".
Previously on Wednesday (5 Dec), Singapore's Minister for Foreign Affairs Vivian Balakrishnan urged Malaysia to "cease" ongoing "provocative intrusions" by the neighbouring nation's vessels into Singapore's maritime territory in order to "avoid escalating tensions on the ground" and to remain compliant "with international law".
In a press release by Singapore's Ministry of Foreign Affairs, which detailed a phone conversation between Dr Balakrishnan and his Malaysian counterpart Saifuddin Abdullah on the same day, Dr Balakrishnan spoke about "Malaysia's recent purported extension of the Johor Bahru Port Limits (JPL)", which he claimed has encroached into "Singapore Territorial Waters off Tuas".
Dr Balakrishnan added, according to the statement by MFA, that "the JPL now extends beyond even the limits of Malaysia's territorial sea claim in the area, as set out in Malaysia's own 1979 map, which Singapore has never accepted".
Berita Harian Online, a Malay-medium mainstream Malaysian news outlet, reported on Wednesday (5 Dec) that Malaysian Prime Minister Dr Mahathir Mohamad has given the assurance that the JPL does not trespass or encroach into Singapore's maritime borders in Tuas.
Dr Mahathir added that Malaysia will ensure that the port's expansion will be carried out at the nation's borders, and that the borders can be measured to verify the accusations made by Singapore.
Bernama reported that Putrajaya has proposed to hold a meeting with Singapore in a bid to resolve the ongoing territorial disputes surrounding the maritime and airspace borders of Malaysia and Singapore.
Following Malaysia's objection to the new flight paths and the Instrument Landing System (ILS) being put in place by Singapore from Seletar Airport, which was raised by Malaysia's Transport Minister Anthony Loke in Parliament on Tuesday (4 Dec), Wisma Putra indicated that the upcoming meeting will involve efforts to find a solution to the ILS problem.
In his statement in Parliament on Tuesday, Mr Loke cited the possibility of the new flight paths and the ILS stunting the development around the industrial Pasir Gudang area in Johor as the reason for objecting Singapore's move.
He added that Singapore had proceeded to broadcast the ILS on 1 Dec without Malaysia's consent, and despite being notified of Malaysia's objection twice on 28 and 29 Nov, adding that the implementation of the ILS without Malaysia's permission violates the principle of national sovereignty as accorded under the Convention of Civil Aviation 1944.
In a separate statement, according to Bloomberg, Mr Loke said that the Malaysian government aims to put forth a counter-proposal to the Civil Aviation Authority of Singapore (CAAS) regarding the new flight paths.
"Our position is loud and clear, the instrument landing system landing approach toward Pasir Gudang is a no-no to us," he said.
Malaysian daily Malay Mail reported that the Malaysian government, in a bid to reclaim the nation's airspace between next year and 2023, will be sending a protest note to the Republic over Singapore's decision to operate its instrument landing system (ILS) for the Seletar Airport near the border with Johor despite Malaysia's protests.
His Singaporean counterpart, however, said that he found it "kind of strange" for the neighbouring nation to flag concerns over the ILS.
"There have always been flights up north, so the procedures take into account existing entities in Pasir Gudang," said Singapore's Transport Minister Khaw Boon Wan in a media statement.
Mr Khaw added that the new flight paths are in line with current flight paths into Seletar, adding that the flight paths have been utilised for decades and are in line with International Civil Aviation Organisation (ICAO) standards.
Singapore's Ministry of Transport (MOT) revealed, according to The Straits Times, that the ILS procedures have been relayed to the Civil Aviation Authority of Malaysia (CAAM) in December last year.
"However, despite repeated reminders, we received no substantive response from CAAM until late November 2018," said the ministry.
MOT added that the new system will not "impose any additional impact on other airspace users as well as businesses and residents in Johor".
The ministry's rationale behind implementing the ILS is to increase safety and precision for pilots approaching the runway and the airport in general via instruments rather than by sight alone.
The implementation of the system is a part of the turboprop operations from Changi Airport to Seletar Airport.


I didn't expect to be interviewing Ben Adamowski for the Reader's first issue. I'd been recruited by pals from Carleton College to be the paper's managing editor and moved into the four-bedroom walk-up at 48th and Dorchester (torn window shades, roaches, mattress on the floor) a couple of weeks earlier. The first issue was intended to be 16 pages filled with free classifieds (I helped copy notices from neighborhood bulletin boards), entertainment listings, feature stories, and about, say, 50 percent display ads. But as deadline day approached, a paltry few ads had been sold and more columns of text were needed. Meanwhile, there wasn't much to edit (or to manage). What to do?
I'd started teaching myself about Chicago, a city I'd visited briefly once before, by reading Mike Royko's Boss on the plane. Ben Adamowski figured prominently, as the only candidate who'd ever been much of a mayoral opponent for Richard J. Daley (back in 1963). I looked in the White Pages (remember those?), found his law office, called him up. Sure, he'd be happy to talk.
For the next six years I taught myself about Chicago. Local history, politics, literature, architecture . . . whatever I learned, I wrote about. There wasn't much background research in my early stories; the stories were the research. History of the skyscraper? Visit the Monadnock Building, 700 words. A view of the west side from the windows of the Halsted bus? One two-hour ride, 1,600 words. After the little display sales problem was worked out (thank you, Ace Hardware!) the paper grew—and needed more words than ever. With more room I developed a smart-alecky style and had fun with "creative" touches (this was the heyday of New Journalism, after all).
When I recall those years I always think of working with a trio of talented photographers: Marc PoKempner, Mike Tappin, Kathy Richland. And several of my earliest pieces ran with distinctive (!!!) illustrations by Andrew Epstein, most memorably the pregnant angel, complete with backpack and pubic hair, who was evidently supposed to symbolize the pending death of the Chicago Maternity Center (March 30, 1973). The center's clients were mostly women of color hoping to give birth at home, not hippie backpackers—but never mind. Epstein's drawings were at least as "alternative" as my writing, and more important to the Reader's identity out on the streets.
Today what strikes me about those old words is how much I loved roaming around the city. It was a rougher, grittier place back then, and Chicago didn't have a Jane Jacobs praising its diversity and livability. But the Reader made it possible for me to discover what a great city this is, and I like to think I helped the Reader's readers discover it too.
Nancy Banks served briefly as the Reader's first managing editor and wrote features and the Neighborhood News column during the Reader's first six years. She then moved to Berkeley, where she cofounded and served as publisher of the East Bay Express. She retired and moved to New York in 1999.


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Cannibalism and activity rate in larval damselflies increase along a latitudinal gradient as a consequence of time constraints
Szymon Sniegula1,
Maria J. Golab1 &
Frank Johansson ORCID: orcid.org/0000-0002-2302-26032
Predation is ubiquitous in nature. One form of predation is cannibalism, which is affected by many factors such as size structure and resource density. However, cannibalism may also be influenced by abiotic factors such as seasonal time constraints. Since time constraints are greater at high latitudes, cannibalism could be stronger at such latitudes, but we know next to nothing about latitudinal variation in cannibalism. In this study, we examined cannibalism and activity in larvae of the damselfly Lestes sponsa along a latitudinal gradient across Europe. We did this by raising larvae from the egg stage at different temperatures and photoperiods corresponding to different latitudes.
We found that the more seasonally time-constrained populations in northern latitudes and individuals subjected to greater seasonal time constraints exhibited a higher level of cannibalism. We also found that activity was higher at north latitude conditions, and thus correlated with cannibalism, suggesting that this behaviour mediates higher levels of cannibalism in time-constrained animals.
Our results go counter to the classical latitude-predation pattern which predicts higher predation at lower latitudes, since we found that predation was stronger at higher latitudes. The differences in cannibalism might have implications for population dynamics along the latitudinal gradients, but further experiments are needed to explore this.
Predation is ubiquitous, and theory as well as empirical studies suggests that predation is higher at lower latitudes [1,2,3]. However, we have little knowledge on how intraspecific predation, more commonly referred to as cannibalism, varies along a latitudinal gradient, but see Pereira et al. [4]. Cannibalism may be density dependent (such that a higher risk is achieved with more potential cannibals), or density independent where cannibalism varies with other environmental variables besides density of conspecifics [5, 6]. In this is study we focus on the density independent cannibalism driven by seasonal time constraints along a latitudinal gradient.
Cannibalism, defined as the killing and eating of individuals of the same species, is common in many organisms [7]. There are several potential advantages. First, there could be a direct, greater nutrient effect from consumption, and hence increased growth and development [8]. Second, there could be an indirect advantage in that a conspecific competitor is eliminated, thus reducing competition in the future; growth and development are also enhanced thereby [9, 10]. Cannibalism does, however, also have certain disadvantages. For example, there is a risk that the potential cannibal becomes the victim [9, 11]. Moreover, there is a risk of cannibalising a related individual, which will decrease inclusive fitness [12]. Finally, there is also a higher risk of pathogen and parasite infection when cannibalising a conspecific compared to preying on a non-specific [13]. Hence, we expect cannibalism to vary with environmental factors and to be more common when the benefits are greater than the costs.
Usually, cannibalism is more common when individuals differ in size, but cannibalism among similarly sized individuals also occurs [7, 14, 15]. In general, cannibalism is higher at high population densities because encounters between individuals increase [16]. Also, resource levels could affect cannibalism intensity. As food levels go down, body condition also deteriorates, which affects cannibalism [17]. For example, when prey is scarce, starvation levels increase, which could increase cannibalism [18]. The higher level of cannibalism in starved individuals is believed to be a result of higher levels of aggression [18]. However, it could also be a result of more encounters between individuals since the encounter rate should go up when starved animals are actively searching for food [19, 20].
One factor that could affect cannibalism is the time constraints that are imposed by seasonality (but see [10, 21]). Seasonal time constraints are set by the variation in temperature that cause the annual cycles of winter and summer [22, 23], and in most situations day length is an environmental cues that can be used for estimation length of the potential season. Note that at higher latitudes a long day length the weeks before and after summer solstice, although it allows for more foraging and growth (since more hours of light are available), actually is a cue that signals seasonal time constraints. Such constraints are common in organisms with complex life cycles, such as insects and amphibians [24,25,26]. Seasonal time constraints usually increase with latitude and altitude because the time available for growth and development decrease with these variables [27]. Similarly, time constraints are stronger in organisms with obligate one-year life cycles, since they have to complete their life cycle within one growing season. An organism with a flexible life cycle could add another year of growth and development if the season is too short, thereby lessening the time constraint. Since cannibalism may increase growth and development by the addition of extra nutrients and the reduction of potential competitors [9, 10], we can hypothesise that cannibalism should increase with the intensity of time constraints. For example, De Block and Stoks [10] found that time constrained damselfly larvae increased cannibalism, which resulted in faster development rate and growth. Hence, along a latitudinal gradient in a species with an obligate one-year life cycle, cannibalism should be stronger in the season time constrained north than in the south. Indeed, many studies have shown that northern populations do have a higher growth and faster development than southern populations, e.g. [27,28,29,30], but no studies have examined how cannibalism varies along a latitudinal gradient.
In this study we focused on non-filial and non-sexual cannibalism in larvae of the damselfly Lestes sponsa (Hansemann). The main aim of the study was to examine how cannibalism changes in damselfly larvae along a latitudinal gradient. We compared populations from three latitudes: south, centre and north. We predict a higher level of cannibalism in the northern populations and a higher level of cannibalism under more time-constrained environmental conditions. Since cannibalism increases with activity we also assessed this behaviour in the larvae. We predict a higher level of activity where time constraints are greater, since these larvae have to search more actively for food. We also predict a positive correlation between cannibalism and activity.
The damselfly Lestes sponsa (Hansemann) has a one-year obligate life cycle consisting of a long-lived aquatic larval stage (2–3 months), during which the main part of growth and development occurs, and a relatively short-lived terrestrial adult stage (days to weeks), when reproduction takes place. The European distribution of L. sponsa ranges from southern France to northern Sweden [31].
We examined cannibalism in L. sponsa under two environmental conditions: a common garden experiment and a simulated natural condition experiment. For both experiments eggs from two replicate lake populations per latitude were collected using a common method [32]. By sampling and analysing two populations per latitude (random population effect) we decreased the influence of lake specific environmental effects. The populations were situated in southern France (43°N), Poland (54°N) and northern Sweden (66°N). Estimates of population densities at these populations are given in Sniegula et al. [30], and in general the densities are lower in the north. The distances between the replicate populations ranged from 5 to 151 km and they were all permanent waters. The temperatures that the eggs and larvae experienced during both experiments were derived from the FLake lake model [33]. For a detailed description of the FLake model, see Sniegula et al. [30]. All applicable institutional and/or national guidelines for the care and use of animals were followed.
Cannibalism: Common garden experiments
For the common garden experiment, eggs were collected on 28 June 2013 at the southern latitude, 28 July 2013 at the central latitude, and 3 Aug 2013 at the northern latitude. We sampled 25, 25 and 50 egg clutches from the southern, central and northern latitudes, respectively. These egg clutches were sampled by catching mating females and putting them separately in small glass jars with a moist filter paper wherein females deposited their eggs. Upon arrival at the laboratory, we placed the eggs in separate plastic containers (12 × 8 cm, height 5 cm) filled with 250 ml of dechlorinated tap water and put them in a climate chamber with temperature 21.9 °C and photoperiod L-D 19:25–4:35. We set this temperature because individuals from each latitude experience it for at least several hours a day during the main growing season in nature [30]. The photoperiod reflected the longest day length at the mid-latitude across our sampled latitudes, 55°N.
After 17 days we initiated winter conditions. We lowered the temperature to 15 °C while maintaining the existing photoperiod regime. The following day we further reduced the temperature to 5 °C and set the light level to 24 h of darkness to simulate winter conditions, which were simulated for 28 days. Thereafter the eggs were transferred to a climate chamber with a constant temperature of 21.9 °C and L-D 19:25–4:35. Importantly, the L-D 19:25–4:35 triggered the eggs from the central and southern latitudes to hatch very synchronously and the northern latitude eggs to hatch synchronously enough for there to be a sufficient number of individuals for the cannibalism experiment [30]. Note that due to different sampling dates (see above), the cannibalism experiment started at different days for each latitude.
The northern latitude eggs hatched 14 days (2 Oct 2013), the central latitude eggs 7 days (26 Sept 2013) and the southern latitude eggs 5 days (27 Aug 2013) after we had transferred them to the climate chamber with the constant summer temperature and light regime. Immediately after hatching, the eggs from all the clutches originating from the two populations per latitude were mixed in a plastic bucket (5 l volume). Thereafter, we randomly divided the hatchlings into groups of ten individuals and introduced them into plastic containers (12 × 8 cm, height 5 cm) filled with 400 ml of dechlorinated tap water. The number of replicates was 50, 25 and 25 for northern, central and southern latitudes, respectively. Each container had two strips of nylon net (14 cm long and 3 cm wide) crossing each other in the centre of the container. The larvae were fed twice a day for 14 days with Artemia nauplii (the mean Artemia portion: 113.25, SD: 10.25, N = 10). We did not observe cannibalism during this time. After 14 days, we reduced the feeding rate to three times a week: Monday, Wednesday and Friday. To check for cannibalism, we counted the individuals every fourth day, and for the statistical comparisons of cannibalism we used the numbers of individuals cannibalized on days 12 and 28, corresponding to an age of 26 and 42 days, respectively. We estimated the rate of cannibalism by taking into account missing and dead individuals with signs of attack (extrinsic causes of death). Damselfly and dragonfly larvae are not scavengers, and only strike against moving prey [34]. We did not observe individuals that died due to intrinsic effects, e.g. due to developmental errors.
Cannibalism: Simulated natural conditions
For the simulated natural condition experiment we collected eggs on 15 June 2015 in southern populations, on 5 Aug 2015 in central populations and on 12 Aug 2015 in northern populations. The populations and the egg sampling method were the same as in the common garden experiment. Similarly, the cannibalism experiment on different latitudes started at different days due to different sampling dates across latitudes. We sampled 20 clutches from the two replicate populations per latitude. After arrival at the laboratory, the eggs were placed in plastic containers filled with 250 ml of dechlorinated tap water and put in climate chambers with temperatures and photoperiods simulating late summer conditions at each latitude of origin of the populations, i.e. the environmental conditions of the source animals. For the northern, central and southern latitudes the temperatures were 19.2 °C, 21 °C and 24.8 °C, respectively, and the photoperiods were L-D 20:57–3:03, 17:38–6:22, and 16:31–7:29, respectively.
Seventeen days after the eggs had been placed in the climate chambers, we initiated simulated winter conditions. We lowered the temperature to 15 °C while maintaining the existing photoperiod regime. The following day (29 Aug 2015, 22 Aug 2015 and 2 July 2015 for the northern, central and southern latitudes, respectively) we reduced the temperature to 5 °C and set the photoperiod to 24 h of darkness. Winter conditions were simulated for 48, 50 and 50 days for northern, central and southern latitudes, respectively.
Immediately after the end of the simulation of winter conditions, as in the common garden experiment, all the eggs were transferred to another climate chamber with temperature 21.9 °C and photoperiod L-D 19:25–4:35. We knew from the previous experiment that such a temperature and photoperiod would trigger synchronous hatching [26]. The northern eggs hatched 10 days (27 Oct 2015), the central eggs 4 days (16 Oct 2015) and the southern eggs 2 days (24 Aug 2015) after the simulation of winter conditions had ended. Directly after hatching, 10 hatchlings were chosen at random from each container (= egg clutch) and transferred to another container (12 × 8 cm, 5 cm high) with 400 ml of dechlorinated tap water with two nylon net strips crossing the inner part of the container. The number of replicates was 20, 20 and 20 for northern, central and southern latitudes, respectively. On the same day, these hatchlings were moved back to their original chambers with programmed spring conditions.
The simulation of spring conditions reflected the dates when the temperature exceeded 12 °C at each latitude: northern latitude, 30 May, 14 °C; central latitude, 25 Apr, 13.3 °C; southern latitude, 4 Apr, 13.8 °C. To simulate the progression of spring and summer, we simulated weekly changes of temperature and photoperiod until the end of the experiment (Additional file 1: Fig. A1). The larvae were fed twice a day with Artemia nauplii (mean nauplii portion: 121.83, SD: 9.48, N = 10). As in the common garden experiment, we reduced the feeding rate to three times per week after 14 days. To check for cannibalism, individuals were counted every fourth day, but for the statistical comparisons of cannibalism we used the number of individuals cannibalized on days 12 and 28, corresponding to an age of 26 and 42 days, respectively. We estimated the rate of cannibalism by taking into account missing and dead individuals with extrinsic causes of death. No individuals died as a result of intrinsic causes. In this experiment we did not mix individuals originating from different families, which allowed us to associate activity level and cannibalism rate at the family level. Hence, all observed cannibalism was within a family (clutch).
Experiment: activity
Activity was estimated on the same group of larvae, i.e. originating from the same egg clutches as were used for the cannibalism experiment performed in the simulated natural conditions in 2015. On the day when the eggs hatched in the climate chamber at 21.9 °C and photoperiod L-D 19:25–4:35 (see above), we randomly chose 8 individuals from each family and placed them individually in round plastic containers (diameter 7 cm, height 4 cm) filled with dechlorinated tap water. Thereafter we reared the larvae under two conditions: 1) common garden conditions (larvae reared in the same chamber as where they had hatched), and, 2) simulating the native latitudinal temperature and photoperiod conditions as described above. We kept individual larvae in separate chambers until the larval activity experiment started, which took an average of 69.4, 70.8 and 58.8 days, respectively, for southern, central and northern latitude populations grown in common garden conditions, and 85.2, 77.0 and 62.5 days for southern, central and northern latitude populations grown in simulated conditions. Larvae were fed every morning and afternoon with Artemia nauplii (mean nauplii portion: 121.83, SD: 9.48, N = 10). Three days after the larvae had moulted into the final instar, we ran the behaviour observations. The larvae were not fed the day prior to the activity observations. On the first day of the activity observation, each larva was removed from the climate chamber and individually placed in a bigger container, 12 × 8 cm, 5 cm high, with a grid of 2 × 2 cm drawn on the bottom. Larvae were allowed to acclimate in the container 30 min before the observations started. After these 30 min 10 laboratory cultured Daphnia sp. of standardized size were introduced and the behavioural observation started. Depending on the number of larvae that reached the appropriate stage on a given day, we observed between 2 and 10 larvae per day. Larval moves were monitored continuously for 20 min by the same person. Activity was scored by measuring movement in relation to the grid pattern (2 × 2 cm squares) at the bottom of each container. A move was recorded when a larva had moved its head (Additional file 1: Figure A2). From these observations we calculated the total number of moves, the total distance moved, and the mean distance per move. All the experiments were run between 11:30 and 15:00. We did not measure activity on the larvae from the cannibalism experiment, since the larvae that were left at the end of the cannibalism experiment differed in age and hence the number of moults they had gone through. Nevertheless, behavioural studies on activity of damselfly larvae show that larvae differ in their personality and that such larval differences are consistent over time, all else being equal. For example, Brodin [35] showed that Lestes congener individuals remained active over time compared with their conspecifics, independent of state or predator treatment. Similarly, general activity did not change among treatments in Lestes sponsa larvae over a four week period in an outdoor field experiment [36]. We therefore suggest that the difference in the experimental design between the cannibalism and the activity estimates did not bias our results.
For all the statistical analyses we used R 3.3.2 [37]. For all models we used Wald χ 2 statistics to test for fixed effects (car package, [38]) and then, if needed, assessed significance of the differences among levels by changing reference level of the categorical variable (latitude). This method does not include multiple testing, since all variables are already included in the model (thus, differences are corrected for all other factors) [39]. In the common-garden experiment we used generalized linear model GLM (glm function, [39]) with binomial error distribution with latitude (three levels) and time in days (two levels), and the interaction between the two as explanatory variables to analyse the difference in number of larvae cannibalized across experimental groups over time. For the simulated natural conditions experiment we used the same model structure to analyse the difference in number of larvae cannibalized over time, except that we added population within region as random effect and run generalized linear mixed model with binomial error distribution, GLMM (glmer function from lme4 package, [40]).
We used GLM function with quasi-Poisson error distribution to account for the overdispersion to analyse the differences in the number of days until one larva was left in each container. Time (days) was a response and latitude was an explanatory variable. We did not include rearing treatment (simulated natural and common-garden conditions) as a factor since the food level and the way we mixed individuals between families differed between these treatments. Hence, we ran separate tests for common garden and simulated conditions.
To analyse the number of moves we used GLMM model (glmer function [40]). To analyse the mean distance per move and the total distance moved we used linear mixed models (lmer function [38]). We log-transformed the variables mean distance per move and the total distance moved to improve the normality of errors. Latitude was a factor and population within a region was a random effect for these three response variables. We used the same model structures when analysing data for simulated and common garden conditions.
To explore whether there was a relationship between cannibalism and activity we used GLM, and to check whether this relationship differed across latitudes we used GLMM (number of moves) and linear mixed model function (mean and total distance moved) (glmer and lmer functions, respectively) [40]. Cannibalism rates were response variables, activity traits were covariates and latitude was a factor. Population within region was a random effect. These relationships were estimated with larvae from the simulated natural condition experiment. We used mean family values, since activity is difficult to estimate during the cannibalism experiments. Hence, we assumed that activity and the cannibalism rate are associated within sibs, and used the average family value on activity and cannibalism as our replicated unit.
The number of larvae cannibalized increased with latitude, and over time (Fig. 1a), and the probabilities of survival of larvae from northern, central and southern populations until day 12 were 0.45, 0.72 and 0.87, respectively, and until day 28 were 0.19, 0.34 and 0.78, respectively. These patterns were significant since the GLMM showed a significant latitude effect (χ 2 2 = 198.259, P < 0.001) and also a significant change over time (χ 2 1 = 79.197, P < 0.001). The interaction between latitude and time was significant (χ 2 2 = 7.609, P = 0.022), indicating higher increase in cannibalism intensity over time in northern populations. In addition, there was a significant difference in the number of larvae cannibalized between all three latitudes (all P-values <0.05).
a, b Number of Lestes sponsa larvae cannibalized at day 12 (filled symbols) and day 28 (open symbols) and c, d number ofdays until only one larva was left in the experiments under simulated and common garden environmental conditions. Error bars are ±SE
The number of days until one larva was left decreased with latitude and thus showed the same latitudinal pattern as for the number of larvae cannibalized (Fig. 1c). Hence, the cannibalism rate at the northern latitude was higher compared to the south (GLM: χ 2 2 = 125.31, P < 0.001). The GLM showed that northern latitude differed significantly from the central (P = 0.002) and southern (P < 0.001) ones, but that the central and southern latitudes did not differ from one another (P = 0.604).
Cannibalism: Common garden
There was a significant latitudinal effect (GLM: χ 2 2 = 26.669, P < 0.001; Fig 1b) and temporal effect (GLM: χ 2 1 = 205.632, P < 0.001) on the number of larvae cannibalized, but no interaction effect (GLM: χ 2 2 = 0.616, P = 0.735). Curiously, cannibalism was higher in northern and southern populations than in central latitudes (both P < 0.001), but cannibalism in northern and southern populations did not differ from one another (P = 0.305). The probabilities of survival of larvae from northern, central and southern populations until day 12 were 0.40, 0.58 and 0.44, respectively, and until day 28 they were 0.14, 0.22 and 0.16, respectively.
There was an overall significant effect on the number of days until one larva remained (GLM: χ 2 2 = 30.078, DF = 2, P < 0.001; Fig. 1d). There was a significant difference between northern and central, and between central and southern latitudes (P < 0.036, for both comparisons), but no difference between northern and southern latitudes (P = 0.951).
In the simulated conditions experiment the number of moves differed between latitudes (χ2 2 = 413.2, P < 0.001). Number of moves was high in the northern latitude, low in the southern latitude and intermediate in the central latitude population (Fig. 2a). There was significant difference between latitudes (P < 0.001 of all pairwise comparisons). In the common garden experiment there was no difference in the number of moves between the populations from the different latitudes (χ 2 2 = 2.056, P = 0.358). Neither of the latitudes differed between each other (all P-values ≥0.172) (Fig. 2b).
a, b Number of moves, c, d mean distance per move, and e, f total distance moved (±SE) in the experiment under (a, c, e) simulated natural light and temperature conditions and (b, d, f) in a common garden experiment with a light and temperature environment simulating a constant average over latitude and time
The mean distance per move was high in southern populations under southern conditions and low in northern populations under northern conditions, and intermediate for the central populations (Fig. 2c). There was overall significance of these differences (χ2 2 = 11.863, P = 0.003). There was a borderline difference between northern and southern latitudes, and between central and southern latitudes (P = 0.055 and P = 0.065, respectively) and no difference between northern and central latitudes (P = 0.858). A similar pattern with respect to latitude was found in the common garden experiment (χ 2 2 = 22.844, P < 0.001; Fig. 2d). There was a difference between northern and southern latitudes (P < 0.001), and between central and southern latitudes (P < 0.001) and no difference between northern and central latitudes (P = 0.708). The total distance moved was high in northern populations under northern conditions, low in southern populations under southern conditions and intermediate in central populations under the central latitude conditions (Fig. 2e), and, in general, these differences between populations were statistically significant (χ 2 2 = 31.812, P < 0.001). Northern latitude differed from central and southern latitude (P = 0.021 and P = 0.013, respectively), but there was no statistical difference between central and southern latitude (P = 0.509). Overall, in the common garden experiment there was a significant difference in the total distance moved between populations (χ2 2 = 8.579, P = 0.014; Fig. 2f). However, when we compared parameter estimates for each level of the variable latitude, we found that there was no difference between northern and southern latitude (P = 0.170), no difference between northern and central latitude (P = 0.318), and borderline difference between central and southern latitudes (P = 0.053).
Correlation between cannibalism and activity
There was a significant effect of the number of moves on the number of larvae cannibalized when latitude was not included in the model (GLM: χ2 1 = 30.477, P < 0.001; Fig 3a). When the significant effect of latitude (χ2 2 = 40.555, P < 0.001; Fig 3a) was included in the model, the number of moves became non-significant (GLMM: χ2 1 = 0.0001, P = 0.993). The number of days until one larva was left was significantly affected by the number of moves (GLM: χ2 1 = 92.82, P < 0.001; Fig 3b), but when the significant effect of latitude (χ2 2 = 15.997, P < 0.001) was included in the model, the number of moves turned to no significant (χ2 1 = 0.601, P = 0.438). These results suggest that the correlations between cannibalism and activity were not statistically detectable at the population level, but instead were detectable across populations, i.e. at the species level. We also used models to examine the relationship between the mean distance moved and the number of larvae cannibalized, and the total distance moved and the number of larvae cannibalized (in both cases using data on the number of larvae cannibalized until day 28 and until one larva was left), and to examine whether latitudes affected cannibalism. The results from these models showed the same patterns as when using the mean number of moves as a response variable. The numerical results and figures are given in Additional file 1: Table A1, Figure A3.
a The number of larvae cannibalized by day 28 and b the number of days until one larva was left, regressed against the number of larval moves during the experiment simulating natural conditions. The regression lines are based on the studied populations at all latitudes: adjusted R 2 = 0.327 and P < 0.001, and adjusted R 2 = 0.142 and P = 0.002 for the (a) and (b) figures, respectively
We found support for our predictions that cannibalism should increase with stronger time constraints, because cannibalism was higher at northern latitude conditions. When northern populations were raised at northern latitude light and temperature conditions, cannibalism was significantly more intense than in the southern populations raised under southern latitude light and temperature conditions. This experiment with simulated environmental conditions does not tell us whether the observed higher level of cannibalism in the north is a fixed genetic effect for more cannibalism or an induced effect caused by the light conditions which simulates a shorter season. However, our common garden experiment suggests that the observed difference is not a pure genetic effect because cannibalism patterns was not similar to the simulated conditions experiment. The common garden experiment used a light regime that simulated a late season photoperiod for newly hatched larvae. Thus, this photoperiod, i.e. the day length, was an environmental cue for seasonal time constraints. This photoperiod simulated a perceived time constraint effect, being high for the southern, intermediate for the central and low (but still time-constrained) for the northern populations (northern populations would have needed a much longer daylight period to simulate very strong time constraints). If it was driven by phenotypic plasticity the southern damselflies would have had the highest level of cannibalism, the central the intermediate and the northern the lowest, but we did not observe this. Nevertheless, our results clearly show that L. sponsa larva reared at environmental conditions simulating natural temperature and light regimes at northern latitudes have higher cannibalism, compared to larvae raised at temperature and light conditions simulating those at southern latitude. However, more experiments are needed to evaluate how much of this is due to genetic and phenotypic plasticity, since northern population did not differ from southern ones in the common garden experiment.
The stronger cannibalism probably accelerates development and growth, although we have no direct evidence for this. However, in a manipulation experiment, De Block and Stoks [10, 21] found that a time-stressed population of Lestes viridis increased cannibalism, and that this cannibalism was correlated with a faster development rate and growth, as a consequence of greater food intake and less intraspecific competition. Such effects are probably adaptive in organisms at high latitudes, and can lead to a larger size at emergence [19, 36].
Cannibalism was mirrored in the pattern of the number of moves and the total distance moved, such that a high activity was correlated with a high level of cannibalism. However, activity and cannibalism were not associated within latitude. Nevertheless, the correlation across latitudes suggests that part of the cannibalism rate is a consequence of more frequent encounters (see also [20]). Larvae that are more time-constrained probably search more actively for prey, which in turn results in a higher encounter rate with conspecifics, and this potentially results in cannibalism. In support of this, Johansson [19] found that activity increased with lower prey density and that this resulted in a higher level of cannibalism in several species of odonate larvae. However, a higher level of cannibalism in more time-constrained individuals could also be an effect of a more general aggressive behaviour per se. Since we only had one alternative prey available in our experiment we cannot rule out the possibility that a general predation effect intensifies faster than cannibalism. However, one alternative prey (Artemia) was present during the experiment and despite this we observed higher cannibalism in northern environmental conditions. An interesting extension of our experiment would have been to provide another damselfly species as an alternative prey.
Nevertheless, the absence of a significant effect of activity on cannibalism when latitude was included in the model, suggests that the relationship between cannibalism and activity was not detectable within latitudes. This implies, that other factors besides activity also might contribute to differences in cannibalism along the latitudinal gradient. For example, more time-constrained animals might be more aggressive because they need more energy to develop and grow faster. Such energy effects of cannibalism was found in spiders where cannibalism was higher in starved larvae compared to non-starved ones [18].
In contrast to the number of moves and distance moved, we found that the mean distance moved was not positively correlated with cannibalism. In fact, it went in the opposite direction for the northern population under simulated conditions, suggesting that it is not important for cannibalism intensity. Northern individuals moved many times and at very short intervals, suggesting a very intensive hunt for prey. This very intensive movement over very short distances could lead to a high encounter rate between potential cannibals if during their first encounters they perceive each other as prey. However, movements and distance moved and their relationship with potential prey is dependent on the density of potential prey and activity of the prey and hence more work is needed to understand how cannibalism is affected by activity and density at a mechanistic level.
Interestingly, we found that the level of cannibalism and activity in southern populations raised in the common garden conditions were as a high as in the northern populations. We interpret this result as an effect of a very strong time constraint on these southern populations under these environmental conditions. The simulated photoperiod mimics a very late season for the southern population, and hence the larvae experience a strong time constraint, which should speed up their development, activity and cannibalism. In contrast, for the northern populations the common garden photoperiod, though simulating a time constraint, through a day length environmental cue, was much less strong. Had we used a longer photoperiod, simulating a stronger time constraint for the northern populations, these populations may have displayed a higher level of cannibalism and activity compared to the southern populations. We also found that number of days until one larvae was left was much shorter in the common garden experiments. This was probably an effect of temperature since temperature was high from the beginning of the experiment in the common garden conditions. Predation rate is temperature dependent in many invertebrates and peaks at optimal temperature [41]. Our comparison was only across latitude and not between the common garden and simulated conditions and therefore this temperature effect should have little impact on the interpretation of our result.
In this study we showed that more time-constrained populations in northern latitudes and individuals subjected to higher time constraints exhibited a higher level of cannibalism. Such higher levels of cannibalism in time-constrained animals have been observed in other studies. For example, studies that manipulated the perceived time available for growth within a season found higher levels of cannibalism in time-constrained damselfly larvae [10, 20, 21]. However, our study is the first to focus on how time constraints and cannibalism are associated using a latitudinal gradient [42]. These cannibalism patterns may affect population dynamics, and whether it has stabilizing or de-stabilizing effects on population dynamics of the cannibalistic population depends on the age and size structure and whether density-dependent effects are due to causes other than cannibalism [43]. The studies reviewed in Claessen et al. [43] focused on biotic variables, however. In contrast, time constraint is an abiotic variable that does not necessarily have the same population dynamic effects as biotic variables since these tend to act on the population independently of population density. Exploring the combined effects of biotic and abiotic effects such as time constraints on population dynamics would be interesting.
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We thank Monika Prus for help in the laboratory experiment, Maciej J Dańko and Michał Żmihorski for advice in statistics, Philippe Lambret for providing information on damselfly populations in southern France, and the Camargue Regional Nature Park, France, for sampling permission in southern France.
SS was supported by the National Science Centre (grant number 2012/05/N/NZ8/00981 and PhD scholarship 2014/12/T/NZ8/00522) and the Institute of Nature Conservation, Polish Academy of Sciences. MJG was partially supported by the Institute of Nature Conservation, Polish Academy of Sciences.
Data available from the Dryad Digital Repository: http://dx.doi.org/10.5061/dryad.s8k68.
Department of Ecosystem Conservation, Institute of Nature Conservation, Polish Academy of Sciences, al. Mickiewicza 33, 31-120, Krakow, Poland
Szymon Sniegula & Maria J. Golab
Department of Ecology and Genetics, Uppsala University, SE-751 05, Uppsala, Sweden
Frank Johansson
Szymon Sniegula
Maria J. Golab
SS, MJG and FJ conceived and designed the experiments. SS and MJG performed the experiments. SS analyzed the data. FJ and SS wrote the manuscript. All authors read and approved the final manuscript.
Correspondence to Frank Johansson.
The research has been carried out within an appropriate ethical framework. The study organism is neither protected by low nor endengenred in coutries where the field sampling was done. Field sampling in France was under the permit of the Camargue Regional Nature Park, France.
Contains Table A1 and Figs. A1–A3. (DOCX 2346 kb)
Sniegula, S., Golab, M.J. & Johansson, F. Cannibalism and activity rate in larval damselflies increase along a latitudinal gradient as a consequence of time constraints. BMC Evol Biol 17, 167 (2017). https://doi.org/10.1186/s12862-017-1010-3
Abiotic constraints
Phenotypic plasticity
Photoperiod
Evolutionary ecology and behaviour