Back when I still harbored doubts about the theory of evolution I used to say that speciation has not actually been observed. This semi-inadvertent island lizard experiment is showing that the process of adaptation may be faster – a lot faster – than previously believed.
Researchers found that the lizards developed cecal valves—muscles between the large and small intestine—that slowed down food digestion in fermenting chambers, which allowed their bodies to process the vegetation’s cellulose into volatile fatty acids.
“They evolved an expanded gut to allow them to process these leaves,” Irschick said, adding it was something that had not been documented before. “This was a brand-new structure.”
Along with the ability to digest plants came the ability to bite harder, powered by a head that had grown longer and wider.
And that’s all just since 1971. It’s not quite speciation yet, but it’s sure heading that way.
Leave a Reply