Module 2.1 Evidence in Evolution

 

One of my favorite predictions of Darwin's idea of descent with modification makes species change through time. In other words, I will be researching evidence on the theory of microevolution. Specifically, I will be looking into evidence of Drosopholas (a species of mosquito) and their loss of chromosomal diversity due to climate change.

    So in this case study, scientists have observed are taking interest in how our earth's rapid global warming is changing some of the biological systems and causing them to adapt quickly in response. Ever since the 1970's the O chromosomal polymorphisms of Drosophila subobscura have been studied in concerns for the correlation between the drastic environmental changes and their adaptive genome. In only a time span of about 16 years, the Drosophila species have lost 18.3% of their chromosomal diversity. These adaptive changes have also been found in many other mosquitoes and insect like species. 

    When the scientist continued to perform this study, their site was located on the south slope of O Pedroso mountain which is in northwestern Spain. The samples we collected by nets sweeping over a banana scented bait. In the lab is where the scientist isolated the chromosomes and stained them. 

As we look at this scatter plot above, we can observe that as time moved forward (scatted plot A), the O chromosomal diversity started to decrease from a 0.31 1-IFR starting diversity and decreasing all the way down to 0.26 1-IFR over a span of just 16 years. The reason that scientists are tying the loss of chromosomal diversity to climate change is because of the similar trends between the two variants. A question that came to my mind while I was reading this scientific article was "Why would their chromosomal diversity descrease with an increase of temperature?" By no means am I a scientist or nor do I know much about Drosophilas, but I wonder if their chromosomes that helped their survival rate increase in cooler environmental conditions has no longer been needed so the genome of this species has chosen to not keep carrying a trait that currently serves no purpose. Just a thought!