September 30, 2019
The extinct Tasmanian tiger, or thylacine, was a marsupial predator with stripes, a pouch for its young, and a skull like a wolf. The thylacine and wolf lived on opposite sides of the globe and diverged from a common ancestral species 160 million years ago. Despite this the similarity in the shape of the two species, in particular their head shape, is striking.
A team of researchers from the University of Melbourne have looked at the genome of the thylacine and the wolf to find out if there was a genetic cause for this similarity. They compared not only the genes of the two species, but also the ‘non-coding’ DNA, which was traditionally thought of as ‘junk DNA’ with no real purpose. In fact, this non-coding DNA plays a role in regulating genes during development.
Sections of non-coding DNA associated with skull structure in both species showed signs of natural selection. This type of similarity can be attributed to convergent evolution, where two distantly related species evolve similar traits in response to similar challenges in their environment. It may be possible that the non-coding DNA is the driving factor behind convergent evolution, a hypothesis that will require further study.
Source: The University of Melbourne
Read more: http://ow.ly/DZJb50wtYH6
