(I originally wrote this up to share my research with my non-scientific friends and family and realized it fits well within the scope of my blog so here you go)
In most phylogenetic studies, the ultimate goal is to construct a tree that accurately reflects evolutionary relationships between species. We used to do this by entirely comparing anatomy, but once DNA sequencing was introduced, things were revealed to be more complicated than we could have anticipated. In the beginnings of DNA sequencing, we were pretty limited in how much we could sequence. People would sequence a single gene and be pretty pumped about their phylogenetic tree. But with advances in sequencing, we learned that the phylogenetic tree created from a single gene merely reflects the history of that gene, not necessarily the species themselves – each gene has its own evolutionary history. So folks were like, okay, we’ll just get a few more genes and maybe a phylogenetic signal will emerge, a consensus between gene trees, thus giving us the true species tree.
Then there’s my project. We sequenced 962 gene regions – surely such an absurd amount of genes that would tell us a relatively clear story of evolutionary history? But it hasn’t. It’s an absolute mess. There is a profound amount of disagreement between all of the genes, each telling a conflicting story about what happened in the past. And I am fascinated with this mess. I looked into this group of species because we suspected hybridization, and this mess of gene histories further supports that – maybe the reason there are so many mixed signals is because we’re not getting genes that have stayed with a single species throughout time, maybe they’ve have been passed between species.
Anyway, I am super super pumped. I’ve wrapped up the project for the purposes of the class I’m doing it for, but I am absolutely going to push further. This is so much more exciting to me than a clean and tidy phylogenetic tree!