Evolutionary biologists are the last people you’d expect to be playing with time travel. But in a recent experiment, that’s just what they appear to have done.
Top it all off with the “resurrection” of an ancient ancestor to an integral component to modern humanity, and you’ve got a case for “alternate” evolutionary paths that show a very different history than the one we all know.
Evolutionary biologists experimenting with the the cellular receptor for cortisol, a hormone produced within the body when it undergoes stress, discovered that the protein could not have evolved within humans to function the way it does today without at least two significant mutations somewhere along the way. More specifically, these mutations were key in allowing the furtherance of later mutation which would allow the evolutionary path leading to our present humanity to become viable.
But what could have been the factors determinant in “steering” the course of human evolution in such a way?
Interestingly, a recent paper published in the journal Nature suggests that it’s all the result of “very unlikely chance events that happened in our deep evolutionary past,” according to Joe Thornton, PhD, a geneticist and professor of ecology and evolution at the University of Chicago. Biochemical processes have allowed researchers like Thornton to study the way that proteins behave, and even to synthesize proteins that function much like the ones which governed ancient processes within the body.
In other words, evolutionary biologists are able to watch the way proteins behaved in the body hundreds of millions of years ago, almost as if they were literally traveling back in time.
To be exact, it was like traveling 450 million years ago, to a time when our ancestors produced what is known today as a glucocorticoid receptor, but not one capable of interacting with cortisol as it does in modern humans. The results of the study help researchers understand the unique role that “permissive mutations” play in evolution, and perhaps most incredibly, the fact that the effects of chance events on evolution is literally contained within a molecule’s atomic structure, almost as if by design.
So what if evolution hadn’t occurred the way it did?
“If evolutionary history could be relaunched from ancestral starting points, we would almost certainly end up with a radically different biology from the one we have now,” Thornton told Phys.org. “Unpredictable genetic events are constantly opening paths to some evolutionary outcomes and closing the paths to others, all within the biochemical systems of our cells.”
Indeed, the world we know today, right down to the roles we play in it and the way we have evolved, could have been vastly different had certain random and unlikely events not occurred. It boggles the mind to consider what kinds of “chance” occurrences on Earth today could be further altering the path we will take, as a species, or how life anything like us on some distant planet might be affected by the outcome of random occurrences that could make them vastly alien in comparison with us.