content
stringlengths 15
400k
| pred_label
stringclasses 1
value | pred_score
float64 0.7
1
|
|---|---|---|
I need a simple windows program that:
- quickly selects an extension by the user typing in part of a name
- dials that number when clicked or press ‘enter’
- find this information from the FreePBX databases
The previous system had a program that did this, and more, but this functionality is really all that’s needed. The UCP is functional, but not as quick to use and the users are accustomed to, and the directory on the phone is ok but also too cumbersome. Quick, simple, and hopefully free.
Anyone know of something suitable?
I think Zulu may be over featured for what I’m looking for.
|
__label__pos
| 0.891676 |
Hello,
I have two college-aged daughters. I work part-time for a home health agency.
I am excited to teach another year with first graders.
|
__label__pos
| 1 |
This video is called Most Beautiful Sea Anemones.
From Wildlife Extra:
Study of sea anemones leads to new branch on the tree of life
A deep-sea animal with tentacles more than six and a half feet long was once thought to be one of the world’s largest sea anemones, but has now been reclassified as belonging to a new order of animals and is not a sea anemone at all.
This animal, previously called Boloceroides daphneae, was discovered in [[phy_address]] Pacific Ocean and labelled as one of the largest sea anemones in existence. But a new DNA-based study led by the American Museum of Natural History shifts it outside of the tree of life for anemones. Instead, researchers have placed it in a newly created order—a classification equal to carnivoria in mammals or crocodilia in reptiles—under the sub-class Hexacorallia, which includes stony corals, anemones, and black corals. The new name of the animal, which lives next to hydrothermal vents, is Relicanthus daphneae.
Relicanthus daphneae is a classic example of convergent evolution, the independent evolution of similar features in species of different lineages.
“Even though this animal looks very much like a sea anemone, it is not one,” said Estefanía Rodríguez, lead author of the report published in the journal PLOS ONE, and an assistant curator in the Museum’s Division of Invertebrate Zoology. “Both groups of animals lack the same characters, but our research shows that while the anemones lost those characters over millions of years of evolution, R. daphneae never had them. Putting these animals in the same group would be like classifying worms and snakes together just because neither have legs.
“The discovery of this new order of Cnidaria—a phylum that includes jellyfish, corals, sea anemones, and their relatives—is the equivalent to finding the first member of a group like primates or rodents. The difference is that most people are far more familiar with animals like chimpanzees and rats than they are with life on the ocean floor. But this amazing finding tells us that we have so much more to learn and discover in the ocean.”
Rodríguez, along with an international team of researchers, conducted a four-year study to organise sea anemones in a “natural,” or phylogenetic way, based on their evolutionary relationships. Sea anemones are stinging polyps that spend most of their time attached to rocks on the sea floor or on coral reefs. Although they vary greatly in size and colour, anemones have very few defining structures. As a result, classifying these animals based on morphology alone can be difficult.
“Anemones are very simple animals,” Rodríguez said. “Because of this, they are grouped together by their lack of characters—for example, the absence of a skeleton or the lack of colony-building, like you see in corals. So it wasn’t a huge surprise when we began to look at their molecular data and found that the traditional classifications of anemones were wrong.”
The researchers compared particular sections of DNA of more than 112 species of anemones collected from oceans around the world. Based on genetic data and the organisation of their internal structures, the scientists reduced the sub-orders of anemones from four to two.
|
__label__pos
| 0.960803 |
Midweek Musings – No Neat Endings
A good ending is important.
Do ever turn to the end of a book to see how it ends so you can relax into the story? Or is that just me?
Do you ever to the end of a film and ask ‘is that it?’, feeling somehow cheated at the loose ends that haven’t been tied, or worse, with a feeling that the actors and directors got bored and just stopped!
|
__label__pos
| 0.83584 |
I finally got around to updating my Music Links List, which is a long list of bands, artists, labels and so on which either love, like, or have heard of.
Each one has a direct link to a relevant website, and also a series of links to other sites with more information (e.g. Discogs.com), or a chance to listen to some music (e.g. Last.fm, Pandora). These links are auto-generated, so in some cases, there may not be an entry.
There are also a few dead links, but I’m in the process of weeding them out, and adding some new entries too. I’m going to try exporting an artist list from iTunes, so there may be a few more entries. Enjoy!
|
__label__pos
| 0.753742 |
is a tissue found in animals typically which generates the force necessary to move parts of ones body.
MUSCLE: "Muscle, is generally made up hundreds of muscle fibres which when stimulated either contract or relax producing movement."
Cite this page: N., Sam M.S., "MUSCLE," in PsychologyDictionary.org, April 7, 2013, https://psychologydictionary.org/muscle/ (accessed December 7, 2022).
|
__label__pos
| 1 |
UNITY TWP., Pa., — Mike Tomlin spoke to Pittsburgh media Tuesday at Saint Vincent College after the Pittsburgh Steelers’ players reported to training camp and ran their conditioning test.
For the most part, the Steelers reported to camp with a clean bill of health. But Tomlin did state that Minkah Fitzpatrick had been added to the team’s NFI (non-football related illness) list and Tyson Alualu had been placed on the PUP (physically unable to perform) list.
“(Fitzpatrick) sustained a wrist injury,” Tomlin said. “He sustained a wrist injury on vacation. I think he fell off a bike. It will create some short term discomfort, but I don’t expect it to be an issue in the overall trajectory of his development and place with this group. It’s just going to create some discomfort or him on the early stages of this.”
The NFI list only prohibits Fitzpatrick from team practices at training camp until he’s healthy enough to practice and is removed from the list. That’s a similar situation as Alualu being on the PUP list, as both shouldn’t miss game time. But both also won’t practice early in training camp.
“Tyson Alualu has been placed on PUP,” Tomlin said. “He has a knee that’s been swelling on him a little bit, probably from over-training. Similar discussion as Minkah; we don’t expect it to be significant from a long term perspective. But it will create some discomfort here in the early stages (of camp).”
Other than Tomlin’s note that the Steelers will treat Larry Ogunjobi’s early days in camp with caution, it appears the Steelers don’t have many injury concerns as practice beings Wednesday.
“We’ll monitor those guys,” Tomlin said. “There’s some other guys with minor things we’ll manage from a rep standpoint. But it won’t affect their designation in terms of participation.”
By CHRIS CARTER
Neither injury appears to be a serious concern for the Steelers’ hopes this season.
Fitzpatrick spoke with media Tuesday in a full scrum with no cast, bandages or anything on his wrists that would have happened with a serious wrist injury.
|
__label__pos
| 0.903834 |
12 pages.
Students will be flying high with their counting skills making this little 1-10 kite booklet.
Children trace and write the numbers + the number words.
Review addition and subtraction skills by singing the song!
Read the booklet aloud as a whole group and review concepts of print too.
|
__label__pos
| 1 |
tired.
you
take
me
apart.
————————
oh my dear sad heart
on far shore you proclaim
the strength of days the hope
of past mistakes restored i
am only ever waiting on a
star to fall from
outer reaches of the
dark, fragrant spaces.
oh the dearest, the best
save all the letters and
re-scatter them, make new
beds we lie in every Saturday
and new songs rewritten
in each small perfection
a confection of the melancholy
perfect symphony of catastrophe.
laid upon disaster oh the
vanishes of deep blue skies
and conflicting pinstripes call
nothing left on wasting time
floating on the current of the
day with light accompanying
you to heaven with a violent
twist, an aching kiss.
|
__label__pos
| 0.977954 |
Have questions? Need more Information?
Mission Foods Malaysia Sdn Bhd
PT 29516, Lengkok Teknologi 2,
Techpark @ Enstek,
71760 Bandar Enstek,
Negeri Sembilan, Malaysia
Tel: (60) 6 7986 988
Fax: (60) 6 7971 526
We value your comments, thoughts and feedback, please use the form below to send through your enquiry.
Please note that we will endeavor to respond to all enquiries in a timely manner and appreciate your understanding if delays occur.
|
__label__pos
| 0.953599 |
Here’s something new I put together for TheRoot. It’s a compilation of summer art festivals. Enjoy!
|
__label__pos
| 1 |
Beautiful Bay view! Waterfront property. Boat Dock. WiFi. Smart TV, Washer/Dryer, Dishwasher.
Cleaning included in rent. No pets or smoking.
Includes pillows. Tenant brings own linens, blankets/bedspreads and towels.
|
__label__pos
| 0.940569 |
- All Superinterfaces:
XmlObject,
XmlTokenSource
public interface CTFrame extends XmlObjectAn XML CT_Frame(@http://schemas.openxmlformats.org/wordprocessingml/2006/main). This is a complex type.
-
-
Nested Class Summary
Nested Classes Modifier and Type Interface Description
static class
CTFrame.FactoryA factory class with static methods for creating instances of this type.
|
__label__pos
| 0.997829 |
This qualification is aimed at those who work as glaziers, installing glass into frames (e.g. windows, doors), and those who work to maintain glazing installations (usually windows and doors). The standards cover the most important aspects of the job. This qualification is at Level 3, and should be taken by those who are experienced, capable of dealing with a wide range of problems, including working with glazing installations that have complex requirements. Candidates will often take a supervisory role, particularly in relation to less experienced workers. They will also work closely with customers and have well-developed customer service skills.
|
__label__pos
| 0.978838 |
A conversation with the feminist activist.
Question: Has feminism succeeded?
Gloria Steinem: It’s hard to measure success when we’re dealing with between 500 and 5,000 years of patriarchy depending on which continent we sit, so I would say feminism has been successful and we have a huge distance to go, huge. For instance, we’ve demonstrated in this and other modern countries or industrialized countries that women can do what men can do, but we have not demonstrated that men can do what women can do therefore children are still mostly raised, hugely mostly raised by women and women in industrialized modern countries end up having two jobs one outside the home and one inside the home. And more seriously than that children grow up believing that only women can be loving and nurturing, which is a libel on men, and that only men can be powerful in the world outside the home, which is a libel on women. So that's huge step we haven’t taken yet.
Question: Will same-sex parenting couples help to challenge these notions?
Gloria Steinem: Both single males who are parents and same-sex couples of men who are raising children that is certainly a great help because those children will grow up knowing that men can be as loving and nurturing as women. They will be much less likely to falsely divide the world into masculine qualities and feminine qualities, but there is a bigger and deeper connection between the women’s movement and gay and lesbian movements, which has always been true. I mean they always come together, and our adversaries are always the same because the male supremacist, patriarchal, ultra-right-wing, whatever you want to... religious fundamentalists, whatever you want to call it is devoted to saying that sex is only moral and okay when it is directed towards having children and occurs in patriarchal marriage, so the children are owned.
So what the means is that both for women, all women, whatever our sexuality, it’s crucial to our health that we are able to separate sexuality from reproduction. I mean whether or not we can control when we give birth is the biggest element in our health, our education, our economic welfare, our life expectancy, everything. So it’s crucial that we are able to separate sexuality and reproduction. And of course same sex couples stand for, in a way, the separation of sexuality from reproduction, so our adversaries are really all the same people.
On campus, sometimes kids ask me, “Well why is the... why are religious fundamentalists against both lesbians and birth control?” You know this seems inconsistent to them. But it’s not. It’s consistent because they are against any form of sexuality, of sexual expression that can’t end in conception, which happens to be a huge lie about human sexuality. Humans can experience the same sexual pleasure whether we can conceive or not. Sexuality has always been for humans a form of communication, a way we express love and caring and bonding, not only a way we have children if we choose to.
Question: Are men and women equal or do they have their own strengths and weaknesses?
Gloria Steinem: But there aren’t two sides. I mean I think what we… We don’t actually know because we’ve been so deeply propagandized with the idea of masculine and feminine we probably don’t know what differences may be in a group sense, but what we do know is that the individual differences are much greater, so the differences between two women are quite likely to be bigger than the differences, generalized differences between males and females as groups for every purpose except reproduction, just as the individual differences between two members of the same race or ethnicity are probably greater than the differences between two races which might just have to do with resistance to certain diseases or you know.
So the purpose of feminism is to free the uniqueness of the individual and to understand that inside each of us is a unique human being who is a combination of heredity and environment. I mean that is a binary too—I never understand why it’s heredity or environment; it’s both—that have for millennia upon millennia combined and resulted in this human being who could never happen before in quite the same way, could never happen again in quite the same way, so the purpose really is to free that in everyone and not look at labels. Obviously there is no such thing as race and in many ways sex is a continuum, not a binary. So it doesn’t make sense to label people in that way. Even when we do that we discover there is a huge overlap. There are perhaps poles of what seem to be masculine and feminine. Then there are 30% of each that are overlapped. That is a lot of people.
So I think if we could just lift up the labels and look at two things one, our uniqueness as individuals and what talents we bring to the world and what... You know there is a person inside every baby, right? And anybody who has ever met a baby knows there is already a person in there. That is one thing and the other thing is community. That human beings are communal beings and that we can’t exist or prosper by ourselves. We need each other’s support.
Question: What would have to happen for feminism to be no longer necessary?
Gloria Steinem: You know I don’t think we know. I never quite trust futurists, either, because I think they’re kind of telling us what they think our future should be. So what I think we need to do is infuse everyday and every action with the kind of values we hope will be in the future, with kindness, with nurturing, with dreams, ambition, using your talents, not resorting to violence, other forms of conflict resolution, with humor, with poetry, with music.
And if we do that one day at a time we don’t exactly know what is going to happen because we don’t know all the circumstances, but since Marx was right about a lot things, but not about one big thing, which is the ends don’t justify the means. The means are the ends, so I would not try to predict. I mean people ask me and I say kind of semi-serious things like: "Well I want to go out of my house and walk in the park and see white men wheeling babies of color and I want those guys to be well paid because…" And to love children, but right now I see women of color wheeling white babies all the time, so I know there is something wrong or I want to pass a newsstand and see erotica, real erotica, which has to do with love and free choice, not pornography, porno means female slavery. It’s all about passive dominance and pain half the time, so you know I can think of signs of success, but I think only those who live in the future will really, really see success, will really be freed and realize more human capabilities.
Question: Is the younger generation of women apathetic about feminism?
Gloria Steinem: No, I mean just even if you look at the public opinion polls as a kind of gross measure feminism is much bigger and stronger than it was in the 70s. The reason you know me is because there were like you know 500 crazy women who were... I mean so we got to be well known. But the fact is that now it’s the issues of… raised by feminism have majority support in all the public opinion polls. The word feminism even though the opposition has tried very hard to demonize it and to call us Femi-Nazis and terrible stuff still it’s there are about a third of American women who self-identify as feminists with no definition and with the definition it’s more than 60%. Actually more women self-identify, even without a definition, than identify as Republicans or Democrats.
So the idea that feminism has not succeeded or that this generation has rejected it is just a new form of the backlash. I mean when I started they would say... or when all of us started that feminism isn’t necessary. Women don’t want these things, you know? And now the form the backlash takes is to say well it used to be necessary, but it’s not anymore. It is the narrative with pretty much all social justice movements. People start to talk about post-racist, post-feminist. What does that mean? We’re clearly not post either. Would you say post-democracy? Clearly we haven’t reached true democracy yet.
Question: Why do some women vote for Republicans even though the party wants to take away their reproductive freedoms?
Gloria Steinem: It’s very difficult. I mean, of course any group of people that has been subordinate absorbs the idea of our own subordination, and that it is natural, and comes to think that the only way to survive is to identify with the powerful. And I think that is not surprising, and it is what happens to a lot of right-wing women. I mean they think they better do what the powerful tell them do otherwise they’ll be in even more trouble. So, I understand that, but anyone with any faith in the future, self respect, hope for themselves... you can’t vote for people who don’t vote for you and that is... There is a whole wonderful book called "The Republican War Against Women" that documents this from the '60s forward. It wasn’t always true. The Republican Party was the first to support the Equal Rights Amendment for instance, but it is true now.
Question: What happened to the Republican Party?
Gloria Steinem: The problem is that the old party of Goldwater, of Rockefeller—who were for instance, pro-choice, who supported the Equal Rights Amendment, who you know...—has been taken over by very ultra rightwing groups, some of whom are real totalitarians and so it looks like and the media treats it as if the country is evenly divided between Republicans and Democrats. Actually I believe there are more independents than either Republicans or Democrats, and yet those are the... that is the choice we have on the party ballot. So frequently people just vote for the party out of power because they’re disappointed or angry at what is happening at the moment. It makes it very volatile, very, very difficult to know. But I still hope that voters will look at the extreme positions of the Republican Party and know how bad they are for all of us.
For instance, the party platform includes a constitutional amendment to the U.S. Constitution which would make a direct relationship between the law and a fertilized egg, which is when they say life begins; every fertilized egg. What that would do in real life is nationalize women’s bodies. You could legally search a women’s womb to see if she was pregnant. You could forcibly restrain her for all nine months of her pregnancy. Really we would be nationalized. This is insane. This is a party that used to be conservative, but now they... you know conservatives might want to get government off the backs of corporations, but not into the wombs of women, not deciding who can marry whom.
So it’s important that we recognize how extreme the Republicans are in almost every case and how against our self-interest it is to vote for them whether or not we are disappointed with the current crew. At least they believe in the Constitution. At least they have an idea of economic justice. The Republicans are devoted to creating more rich folks. In this country the salary of the average CEO in 1970 was I think 70 times the average worker. Now it is 1,000 times the average worker. And this is bad for all of us because when you give more money to the very rich they don’t spend that much of it as consumers, but when you give it to the middle class they spend most of it, all of it, as consumers and it’s what drives… it’s why this economy is 70% driven by consumer purchases. So it’s good for everybody to diminish this huge social division and restore ideas of individual rights, which are in our constitution and which many of the republican candidates just don’t represent. It’s... I hope that real Republicans take back the Republican Party soon because the problem now is that a real centrist conservative Republican can’t get through the primaries to get to the general election.
Question: Why are mama grizzlies an inappropriate mascot for Sarah Palin?
Gloria Steinem: Well first of all, if Hilary Clinton hadn’t come within very close to the White House we would not see the Republicans recruiting obedient women. So it’s not really Sarah Palin's fault that she got named to be Vice President when obviously she was not prepared for this kind of position. In her current incarnation she has frequently talked about "mama grizzlies" as being kind of representing right-wing women and that is such a libel on mama grizzlies, who are so different. I actually researched them, inspired by her, and discovered that they are famous for their exertion of reproductive control in their lives. That even compared to other bears, brown bears say, they mate later; they have only one or two cubs instead of four; they wait four years instead of two between having cubs; and even once they’re pregnant if they see that it’s going to be a really hard winter, they themselves are not in good health or the food supply is low they reabsorb, their bodies reabsorb the fetus.
So, I mean, they are kind of the prophets. If you wanted to have a totem for reproductive freedom as a fundamental human right the mama grizzlies would be up there.
Question: What’s wrong with the political discourse about abortion?
Gloria Steinem: Well the democrats, many democrats in tight races have suddenly started talking about abortion when before even sympathetic ones who voted for that as a right to privacy and a woman and her doctor make the decision, even they didn’t want to talk about it. They sort of hoped it would go away. So as a result they really don’t know how to talk about it and they confine it to being a "social issue" and this is an "economic year."
Now it happens that first of all it’s not a social issue. It’s a fundamental human right to decide to have children or not to have children. But also it’s the biggest economic influence in a woman’s life whether she can decide when and whether to have children or not. They just are not phrasing it in the proper way, so it makes even voters think "Oh well, one in three women needs an abortion at some time in her lifetime and that is only once and even if it’s criminal and even if it’s dangerous, the fact is the economy affects us every day." But whether you have children or not is the biggest factor of a lifetime in your economic status... or whether you can decide when to have children.
So they’re just not… they just don’t understand how to talk about it even though we’ve been trying to say this for 40 years, so I wrote that op-ed in order to try to say to voters we have do it. We have to know how these folks stand. For instance, there is a candidate for governor of Illinois named Brady who not only loves assault weapons, not only thinks that guns should not be registered and all past registrations should be destroyed, but is also against equal pay—against any enforcement of equal pay—and is for the Human Life Amendment, which would nationalize women’s bodies, so I mean this is the perfect recipe for barefoot and pregnant. Women become what these authoritarian groups have in mind, which is cheap labor ourselves, as workers, and sources of ever-more-cheap labor.
Question: Can stripping or prostitution ever be empowering for women?
Gloria Steinem: The word "empower" is troubling. I mean I have spent 40 years talking to women. I sat before the election, interviewed prostituted women in Las Vegas and so it isn’t... You know little girls do not wake up in the morning and say "I dream of being a prostitute." It is a terrible, terrible life. Body invasion is more traumatic than even getting beaten up. In certain circumstances, obviously, it may be a way to survive. And we rationalize ways to survive. But I think what we need to look at is we need to pull back and say to ourselves why is it that men need... some men; it’s actually not the majority of men... but that some men go to prostitutes and need that kind of dominance. It’s the disease of... It’s getting addicted to masculinity. What is that about?
In the egalitarian cultures... People think prostitution has always existed, but it hasn’t and even rape was very rare. For instance, when Europeans arrived on this continent they wrote about how shocked they were that the 500 or so native groups here didn’t rape even their female captives. They were shocked. So we need to stop asking so many questions of the people who are in various circumstances and feel they have to do this and start asking on the demand side why is there a demand for this. What has been eroticized by male dominant systems of all kinds is dominance and passivity. We need to eroticize equality. I always say to audiences of men: "Cooperation beats submission. Trust me." At least it makes them laugh. That is what is troubling and of course in the meantime we have to stop arresting prostitutes and not arresting traffickers and pimps. It’s absurd. We’re arresting the victim or the survivor and not the oppressor.
|
__label__pos
| 0.958184 |
Looking for a specific article?
Recently I spent a weekend at Download, a heavy metal festival held in the middle of England. For obvious reasons it hasn’t taken place for
No, it’s not thank you and goodbye for me. This Tinnitus Tuesday is a thank you to my first meditation and mindfulness teacher, my Dad,
|
__label__pos
| 1 |
Arsenal team players, Right back; Bacary Sagna, central midfielder Per Mertesacker and new signing, Lukas Podolski arrived in Nigeria to attend the Malta Guinness Low Sugar Workout.
Kaffy, being the number one dancer in Nigeria, taught them some azonto and etighi moves. Malta Guinness and airtel sponsored the event.
|
__label__pos
| 1 |
LIVE HOUSEPLANT Gold Dust Dracaena Spotted. In small plastic pot. Order soon before COLD WEATHER SETS IN OR WAIT UNTIL WARM WEATHER IN SPRING.
|
__label__pos
| 1 |
Wakema is located in Myanmar country, in Southeast Asia continent (or region). DMS latitude longitude coordinates for Wakema are: 16°36'11.99"N, 95°10'58.01"E.
• Latitude position: Equator ⇐ 1846km (1147mi) ⇐ Wakema ⇒ 8161km (5071mi) ⇒ North pole.
• Longitude position: Prime meridian ⇒ 10015km (6223mi) ⇒ Wakema. GMT: +6.5h.
• Local time in Wakema: Saturday 1:57 am, December 3, 2022. [*time info]
Step for grid lines is 15°. On second map 15° latitude and 90° longitude line is numbered. Map pointer shows the 16.6, 95.18 lat-long coordinates.
» Sharing is cool
⇑TOP⇑
Latitude Longitude tools
[*time info] Shown time is in moment when this page is generated. For more accurate time in Wakema visit timein.org (new window).
|
__label__pos
| 0.95381 |
Archosaurs are a group of diapsid amniotes whose living representatives consist of birds and crocodilians. This group also includes all extinct non-avian dinosaurs, extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most recent common ancestor of living birds and crocodilians. It includes two main clades: Pseudosuchia, which includes crocodilians and their extinct relatives, and Ornithosuchia, which includes birds and their extinct relatives (such as non-avian dinosaurs and pterosaurs).
Contents
- Pl exam 2 lepidosaurs vs archosaurs avi
- Distinguishing characteristics
- Origins
- Archosaur takeover in the Triassic
- Main forms
- Modern classification
- History of classification
- Phylogeny
- Extinction and survival
- Hip joints and locomotion
- Diet
- Land water and air
- Metabolism
- Respiratory system
- Reproduction
- References
Distinguishing characteristics
Archosaurs can be distinguished from other tetrapods on the basis of several synapomorphies, or shared characteristics, first found in a common ancestor. The simplest and most widely agreed synapomorphies of archosaurs include teeth set in sockets, antorbital and mandibular fenestrae (openings in front of the eyes and in the jaw, respectively), and a fourth trochanter (a prominent ridge on the femur). Being set in sockets, the teeth were less likely to be torn loose during feeding. This feature is responsible for the name "thecodont" (meaning "socket teeth"), which paleontologists used to apply to many Triassic archosaurs. Some archosaurs, such as birds, are secondarily toothless. Antorbital fenestrae reduced the weight of the skull, which was relatively large in early archosaurs, rather like that of modern crocodilians. Mandibular fenestrae may also have reduced the weight of the jaw in some forms. The fourth trochanter provides a large site for the attachment of muscles on the femur. Stronger muscles allowed for erect gaits in early archosaurs, and may also be connected with the ability of the archosaurs or their immediate ancestors to survive the catastrophic Permian-Triassic extinction event.
Origins
There is some debate about when archosaurs first appeared. Those who classify the Permian reptiles Archosaurus rossicus and/or Protorosaurus speneri as true archosaurs maintain that archosaurs first appeared in the late Permian. Some taxonomists classify both Archosaurus rossicus and Protorosaurus speneri as archosauriforms (not true archosaurs but very closely related); these taxonomists maintain that archosaurs first evolved from archosauriform ancestors during the Olenekian stage of the Early Triassic. The earliest archosaurs were rauisuchians, such as Scythosuchus and Tsylmosuchus, both of which have been found from Russia and date back to the Olenekian.
Archosaur takeover in the Triassic
Synapsids (a group including mammals and their extinct relatives, which are often referred to as "mammal-like reptiles") were the dominant land vertebrates throughout the Permian, but most perished in the Permian-Triassic extinction event. Very few large synapsids survived the event, although one form, Lystrosaurus (an herbivorous dicynodont), attained a widespread distribution soon after the extinction.
But archosaurs quickly became the dominant land vertebrates in the Early Triassic. The two most commonly suggested explanations for this are:
However, this theory has been questioned, since it implies synapsids were necessarily less advantaged in water retention, that synapsid decline coincides with climate changes or archosaur diversity (neither of which tested) and the fact that desert dwelling mammals as well adapted in this department as archosaurs, and some cynodonts like Trucidocynodon were large sized predators.
Main forms
Since the 1970s, scientists have classified archosaurs mainly on the basis of their ankles. The earliest archosaurs had "primitive mesotarsal" ankles: the astragalus and calcaneum were fixed to the tibia and fibula by sutures and the joint bent about the contact between these bones and the foot.
The Pseudosuchia appeared early in the Triassic. In their ankles, the Astragalus was joined to the Tibia by a suture and the joint rotated round a peg on the astragalus which fitted into a socket in the calcaneum. Early "crurotarsans" still walked with sprawling limbs, but some later crurotarsans developed fully erect limbs (most notably the Rauisuchia). Modern crocodilians are crurotarsans that can walk with their limbs sprawling or erect depending on speed of locomotion.
Euparkeria and the Ornithosuchidae had "reversed crurotarsal" ankles, with a peg on the calcaneum and socket on the astragalus.
The earliest fossils of Avemetatarsalia ("bird ankles") appear in the Carnian age of the late Triassic, but it is hard to see how they could have evolved from crurotarsans — possibly they actually evolved much earlier, or perhaps they evolved from the last of the "primitive mesotarsal" archosaurs. Ornithodires' "advanced mesotarsal" ankle had a very large astragalus and very small calcaneum, and could only move in one plane, like a simple hinge. This arrangement, which was only suitable for animals with erect limbs, provided more stability when the animals were running. The ornithodires differed from other archosaurs in other ways: they were lightly built and usually small, their necks were long and had an S-shaped curve, their skulls were much more lightly built, and many ornithodires were completely bipedal. The archosaurian fourth trochanter on the femur may have made it easier for ornithodires to become bipeds, because it provided more leverage for the thigh muscles. In the late Triassic, the ornithodires diversified to produce dinosaurs and pterosaurs.
Modern classification
Archosauria is normally defined as a crown group, which means that it only includes descendants of the last common ancestors of its living representatives. In the case of archosaurs, these are birds and crocodilians. Archosauria is within the larger clade Archosauriformes, which includes some close relatives of archosaurs, such as proterochampsids and euparkeriids. These relatives are often referred to as archosaurs despite being placed outside of the crown group Archosauria in a more basal position within Archosauriformes. Historically, many archosauriforms were described as archosaurs, including proterosuchids and erythrosuchids, based on the presence of an antorbital fenestra. While many researchers prefer to treat Archosauria as an unranked clade, some continue to assign it a traditional biological rank. Traditionally, Archosauria has been treated as a Superorder, though a few 21st century researchers have assigned it to different ranks including Division and Class.
History of classification
Archosauria as a term was first coined by American paleontologist Edward Drinker Cope in 1869, and included a wide range of taxa including dinosaurs, crocodilians, thecodonts, sauropterygians (which may be related to turtles), rhynchocephalians (a group that according to Cope included rhynchosaurs, which nowadays are considered to be more basal archosauromorphs, and tuataras, which are lepidosaurs), and anomodonts, which are now considered synapsids. It was not until 1986 that Archosauria was defined as a crown-clade, restricting its use to more derived taxa.
Cope's term was a Greek-Latin hybrid intended to refer to the cranial arches, but has later also been understood as "leading reptiles" or "ruling reptiles" by association with Greek ἀρχός "leader, ruler".
The term "thecodont", now considered an obsolete term, was first used by the English paleontologist Richard Owen in 1859 to describe Triassic archosaurs, and it became widely used in the 20th century. Thecodonts were considered the "basal stock" from which the more advanced archosaurs descended. They did not possess features seen in later avian and crocodilian lines, and therefore were considered more primitive and ancestral to the two groups. With the cladistic revolution of the 1980s and 90s, in which cladistics became the most widely used method of classifying organisms, thecodonts were no longer considered a valid grouping. Because they are considered a "basal stock", thecodonts are paraphyletic, meaning that they form a group that does not include all descendants of its last common ancestor: in this case, the more derived crocodilians and birds are excluded from "Thecodontia" as it was formerly understood. The description of the basal ornithodires Lagerpeton and Lagosuchus in the 1970s provided evidence that linked thecodonts with dinosaurs, and contributed to the disuse of the term "Thecodontia", which many cladists consider an artificial grouping.
With the identification of "crocodilian normal" and "crocodilian reversed" ankles by Sankar Chatterjee in 1978, a basal split in Archosauria was identified. Chatterjee considered these two groups to be Pseudosuchia with the "normal" ankle and Ornithosuchidae with the "reversed" ankle. Ornithosuchids were thought to be ancestral to dinosaurs at this time. In 1979, A.R.I. Cruickshank identified the basal split and thought that the crurotarsan ankle developed independently in these two groups, but in opposite ways. Cruickshank also thought that the development of these ankle types progressed in each group to allow advanced members to have semi-erect (in the case of crocodilians) or erect (in the case of dinosaurs) gaits.
Phylogeny
In many phylogenetic analyses, archosaurs have been shown to be a monophyletic grouping, thus forming a true clade. One of the first studies of archosaur phylogeny was authored by French paleontologist Jacques Gauthier in 1986. Gauthier split Archosauria into Pseudosuchia, the crocodilian line, and Ornithosuchia, the dinosaur and pterosaur line. Pseudosuchia was defined as all archosaurs more closely related to crocodiles, while Ornithosuchia was defined as all archosaurs more closely related to birds. Proterochampsids, erythrosuchids, and proterosuchids fell successively outside Archosauria in the resulting tree. Below is the cladogram from Gauthier (1986):
In 1988, paleontologists Michael Benton and J.M. Clark produced a new tree in a phylogenetic study of basal archosaurs. As in Gauthier's tree, Benton and Clark's revealed a basal split within Archosauria. They referred to the two groups as Crocodylotarsi and Ornithosuchia. Crocodylotarsi was defined as an apomorphy-based taxon based on the presence of a "crocodile-normal" ankle joint (considered to be the defining apomorphy of the clade). Gauthier's Pseudosuchia, by contrast, was a stem-based taxon. Unlike Gauthier's tree, Benton and Clark's places Euparkeria outside Ornithosuchia and outside the crown group Archosauria altogether.
The clades Crurotarsi and Ornithodira were first used together in [[phy_address]] Paul Sereno and A.B. Arcucci in their phylogenetic study of archosaurs. They were the first to erect the clade Crurotarsi, while Ornithodira was named by Gauthier in 1986. Crurotarsi and Ornithodira replaced Pseudosuchia and Ornithosuchia, respectively, as the monophyly of both of these clades were questioned. Sereno and Arcucci incorporated archosaur features other than ankle types in their analyses, which resulted in a different tree than previous analyses. Below is a cladogram based on Sereno (1991), which is similar to the one produced by Sereno and Arcucci:
Ornithodira and Crurotarsi are both node-based clades, meaning that they are defined to include the last common ancestor of two or more taxa and all of its descendants. Ornithodira includes the last common ancestor of pterosaurs and dinosaurs (which include birds), while Crurotarsi includes the last common ancestor of living crocodilians and three groups of Triassic archosaurs: ornithosuchids, aetosaurs, and phytosaurs. These clades are not equivalent to "bird-line" and "crocodile-line" archosaurs, which would be branch-based clades defined as all taxa more closely related to one living group (either birds or crocodiles) than the another.
Benton proposed the name Avemetatarsalia in 1999 to include all bird-line archosaurs (under his definition, all archosaurs more closely related to dinosaurs than to crocodilians). His analysis of the small Triassic archosaur Scleromochlus placed it within bird-line archosaurs but outside Ornithodira, meaning that Ornithodira was no longer equivalent to bird-line archosaurs. Below is a cladogram modified from Benton (2004) showing this phylogeny:
In Sterling Nesbitt's 2011 monograph on early archosaurs, a phylogenetic analysis found strong support for phytosaurs falling outside Archosauria. Many subsequent studies supported this phylogeny. Because Crurotarsi is defined by the inclusion of phytosaurs, the placement of phytosaurs outside Archosauria means that Crurotarsi must include all of Archosauria. Nesbitt reinstated Pseudosuchia as a clade name for crocodile-line archosaurs, using it as a stem-based taxon. Below is a cladogram modified from Nesbitt (2011):
Extinction and survival
Crocodilians, pterosaurs and dinosaurs survived the Triassic–Jurassic extinction event about 200 million years ago, but other archosaurs became extinct.
Non-avian dinosaurs and pterosaurs perished in the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago, but birds (the only remaining dinosaur group) and crocodilians survived. Both are descendants of archosaurs, and are therefore archosaurs themselves under phylogenetic taxonomy.
Crocodilians (which include all modern crocodiles, alligators, and gharials) and birds flourish today. It is generally agreed that birds have the most species of all terrestrial vertebrates.
Hip joints and locomotion
Like the early tetrapods, early archosaurs had a sprawling gait because their hip sockets faced sideways, and the knobs at the tops of their femurs were in line with the femur. In the early to middle Triassic, some archosaur groups developed hip joints that allowed (or required) a more erect gait. This gave them greater stamina, because it avoided Carrier's constraint, i.e. they could run and breathe easily at the same time. There were two main types of joint which allowed erect legs:
It has been pointed out that an upright stance requires more energy, so it may indicate a higher metabolism and a higher body temperature.
Diet
Most were large predators, but members of various lines diversified into other niches. Aetosaurs were herbivores and some developed extensive armor. A few crocodilians were herbivores, e.g., Simosuchus, Phyllodontosuchus. The large crocodilian Stomatosuchus may have been a filter feeder. Sauropodomorphs and ornithischian dinosaurs were herbivores with diverse adaptations for feeding biomechanics.
Land, water and air
Archosaurs are mainly portrayed as land animals, but:
Metabolism
The metabolism of archosaurs is still a controversial topic. They certainly evolved from cold-blooded ancestors, and the surviving non-dinosaurian archosaurs, crocodilians, are cold-blooded. But crocodilians have some features which are normally associated with a warm-blooded metabolism because they improve the animal's oxygen supply:
So, why did natural selection favour the development of these features, which are very important for active warm-blooded creatures, but of little apparent use to cold-blooded aquatic ambush predators that spend the vast majority of their time floating in water or lying on river banks?
Paleontological evidence shows that the ancestors of living crocodilians were active and endothermic (warm-blooded). Some experts believe that their archosaur ancestors were warm-blooded as well. Physiological, anatomical, and developmental features of the crocodilian heart support the paleontological evidence and show that the lineage reverted to ectothermy when it invaded the aquatic, ambush predator niche. Crocodilian embryos develop fully 4-chambered hearts at an early stage. Modifications to the growing heart form a pulmonary bypass shunt that includes the left aortic arch, which originates from the right ventricle, the foramen of Panizza between the left and right aortic arches, and the cog‐tooth valve at the base of the pulmonary artery. The shunt is used during diving to make the heart function as 3-chambered heart, providing the crocodilian with the neurally controlled shunting used by ectotherms. The researchers concluded that the ancestors of living crocodilians had fully 4-chambered hearts, and were therefore warm-blooded, before they reverted to a cold-blooded or ectothermic metabolism. The authors also provide other evidence for endothermy in stem archosaurs. It is reasonable to suggest that later crocodilians developed the pulmonary bypass shunt as they became cold-blooded, aquatic, and less active.
If the original crocodilians and other Triassic archosaurs were warm-blooded, this would help to resolve some evolutionary puzzles:
Respiratory system
A recent study of the lungs of the American alligator has shown that the airflow through them is unidirectional, moving in the same direction during inhalation and exhalation. This is also seen in birds and many non-avian dinosaurs, which have air sacs to further aid in respiration. Both birds and alligators achieve unidirectional air flow through the presence of parabronchi, which are responsible for gas exchange. The study has found that in alligators, air enters through the second bronchial branch, moves through the parabronchi, and exits through the first bronchial branch. Unidirectional airflow in both birds and alligators suggests that this type of respiration was Present in basal Triassic archosaurs and their non-dinosaurian descendants, including phytosaurs, aetosaurs, rauisuchians, crocodylomorphs, and pterosaurs. The use of unidirectional airflow in the lungs of archosaurs may have given the group an advantage over synapsids, which had lungs where air moved tidally in and out through a network of bronchi that terminated in alveoli, which were cul-de-sacs. The better efficiency in gas transfer seen in archosaur lungs may have been advantageous during the times of low atmospheric oxygen which are thought to have existed during the Mesozoic.
Reproduction
Most archosaurs are oviparous. Birds and crocodilians lay hard-shelled eggs, as did extinct dinosaurs, pterosaurs and crocodylomorphs. Hard-shelled eggs are present in both dinosaurs and crocodilians, and have been used as an argument for the apparent absence of vivipary or ovovivipary in archosaurs. However, both pterosaurs and baurusuchids have soft-shelled eggs, implying that hard shells are not a plesiomorphic condition. The pelvic anatomy of Cricosaurus and other metriorhynchids,. as well as fossilized embryos belonging to the non-archosaur archosauromorph Dinocephalosaurus, collectively suggest that the lack of viviparity among archosaurs may be a consequence of lineage-specific restrictions.
Archosaurs are ancestrally superprecocial, as evidenced in various dinosaurs, pterosaurs and crocodylomorphs. However, parental care did evolve independently multiple times in crocodilians, dinosaurs and aetosaurs. Even in most such species, however, the animals bury their eggs, and are reliant on temperature-dependent sex determination. The exception are Neornithes, which incubate their eggs and rely on genetic sex determination, a trait that might have given them an advantage over other dinosaurs.
|
__label__pos
| 0.941648 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.