biology week 5 assignments

The Complexity of Life

How do you now suppose new species emerge?

There are four current theories regarding geographic Speciation- allopatric, Peripatric, Parapatric, and Sympatic 

During allopatric speciation, a population splits into two geographically isolated populations due to geographical change. The isolated populations then undergo genotypic and/or phenotypic divergence because they are living under different conditions. Peripatric speciation is actually a type of allopatric speciation that results from isolation. This isolation may be the result of geographic isolation or a single ecological event that terminates most of the population. With such a small gene pool, rare genes are passed down more often, which causes changes in the pre-existing species. During Parapatric Speciation species are not isolated by a physical barrier and instead co-exist yet do not mate across the entire population. The causation factors that contribute to individuals within the population to selectively breed remains unknown Sympatic Speciation sympatic speciation is another type of reproductive isolation. Reproductive isolation may be due to individuals coming into their mating seasons at different times or preference of where to find a mate.

Speciation also occurs through human cultivation and manipulation of the environment.

A rad article

http://www.simonsfoundation.org/quanta/20140604-evolving-with-a-little-help-from-our-friends/

Do you vote for the chicken or the egg?

I think it makes the most sense that the “chicken” egg came first, but that it was a result of speciation from another similar species. I also just like imagining ostriches giving birth to chickens and being totally confused.