These are means by which one species becomes multiple species. The difference is actually pretty simple: In allopatric speciation, a population becomes separated by some kind of geographical barrier that prevents genetic mixing. A simple example would be a pond that was once part of a river. The animals on either side of the barrier would now be subject to selective pressure independently. This is the most common type of speciation. In Sympatric speciation, species diverge without physical separation. One of the best studied examples of this is the rift lakes of Africa.
Manassas 10 Day Weather. 1  Thursday:The Manassas forecast for Apr 20 is 72 degrees and Partly cloudy. There is 60 percentage chance of rain and 3 mph winds from the South-Southwest. 2  Friday:The Manassas forecast for Apr 21 is 75 degrees and Sunny. There is 58 percentage chance of rain and 7 mph winds from the West.
Over the course of the year, the temperature in Managua typically varies from 71Â°F to 94Â°F and is rarely below 67Â°F or above 97Â°F. The hot season lasts for 50 days, from March 23 to May 12, with an average daily high temperature above 93Â°F. The hottest day of the year is April 25, with an average high of 94Â°F and low of 76Â°F.