As I explained before, “The hypothesis of front-loading evolution would thus predict that significant transitions in evolution would depend on preadaptation.”
Recently, I discussed one such candidate – the origin of mitochondria.
A new paper has come out that strengthens this case for preadaptation:
“We have now come to understand the processes that drove cell evolution. For some time now the crux of this problem has been to understand how eukaryotes first came to be. The critical step was to transform small bacteria, passengers that rode within the earliest ancestors of these cells, into mitochondria, thereby beginning the evolution of more complex life-forms,” Professor Lithgow said.
The team found that the cellular machinery needed to create mitochondria was constructed from parts pre-existing in the bacterium. These parts did other jobs for the bacterium, and were cobbled together by evolution to do something new and more exciting.
“Our research has crystallised with work from other researchers around the world to show how this transformation happened very early on — that the eukaryotes were spawned by integrating the bacterium as a part of themselves. This process jump-started the evolution of complex life much more rapidly than was previously thought.”
“This will surprise and may even spark debate. However our research compliments the basic rules of life. Even at the molecular level, the rules of the game are the same. Evolution drives biology to more and more complex forms,” Professor Lithgow said.
Hmmm. Evolution “drives biology to more and more complex forms” where pre-existing parts jump start the rapid construction of “new and more exciting” things. Sounds like front-loading at work. And given that these parts might, in turn, facilitate and channel certain changes on a larger scale, it would seem the ground underneath the hypothesis of front-loading continues to solidify.