Kara's Evolution Blog

Genetic Drift - The Bottleneck Effect The population starts off normally. Then a catastrophic event happens, a chasm opens up in the cats' habitat and swallows up a good chunk of the population. This chasm, as a result, erases all of the orange cat population. The orange cat population did not go extinct because they were not "fit" enough or "good" enough to survive, this was simply due to random chance. The grey or calico cats are not better adapted, they just got lucky they were not in the area where the chasm opened up in. By luck, the grey and calico cats survived. The not-so-lucky orange cats go extinct, which will change the allelic frequency of the population due to this random catastrophic event. This illustrates the bottleneck effect. Genetic Drift - The Founder Effect The population starts off normally. There is a dry river in between the high land, and the lowland. Some of the cats get curious and decide to wander off to the lowland to see what is ove...

Phenotypic plasticity, and how to determine if the trait is plastic or not! Check out my youtube video for the explanation! :)

Phenotype is the outside characteristics that is changed by genotype and affects the survival of the species involved. Selection acts on phenotype to produce evolutionary change as it is what affects the survival of the specifies involved. If it is a beneficial phenotype that increases survival rate, it will then increase the reproduction rate of that species that will produce evolutionary change as the members of the species with the beneficial phenotype will outlast those without the beneficial phenotype, thus producing more offspring with the genotype for the beneficial phenotype. 

How an individual in a population's absolute fitness can be different than their relative fitness.  The traits and population can be real or imaginary.  Then  take the population through positive selection  on any trait you choose, explain how the population changes, over what time periods, and what drives the changes. 

'Survival of the good enough' is a more accurate description of natural selection than 'survival of the fittest' because not every species has to be the fittest to survive long enough to reproduce. Using 'survival of the good enough' is more accurate because most species aren't the strongest or the best, they are just able to survive long enough to be able to reproduce.   'Survival of the good enough' relates to natural selection, as this survival is what drives evolution. Those species that are able to survive long enough to reproduce will have their genes passed down to the next generation!

1.) A great example of convergence from the "Improbably Destinies" Chapter 1 was the example of caffeine-producing species. 2.) Convergent evolution is when multiple species have similar traits but do not have a common ancestor. The multiple species independently evolve these similar traits. Divergent evolution is quite the opposite of convergent evolution. Divergent evolution is when related species have evolved similar traits, while convergent evolution is for species who have evolved similar traits and do not have a common ancestor. 3.) The example in #1 showcases convergent evolution because it talks of how these multiple species, cacao, tea, and coffee all produce caffeine but they are on different branches of the evolutionary tree as the diagram below shows. This shows that these species, cacao, tea, and coffee all evolved the caffeine-producing trait independently from one another.  4.) Due to natural selection, these species could have developed convergent features be...