Human activities could change the pace of evolution, similar to what occurred 66 million years ago when a giant asteroid wiped out the dinosaurs, leaving modern birds as their only descendants. That's one conclusion drawn by the authors of a new study published in Systematic Biology .
Jacob Berv from Cornell University and Daniel Field from University of Bath suggest that the meteor-induced mass extinction (a.k.a. the K-Pg event) led to acceleration in the rate of genetic evolution among its avian survivors. These survivors may have been much smaller than their pre-extinction relatives, the Cornell University press release says.
"There is good evidence that size reductions after mass extinctions may have occurred in many groups of organisms," says Berv. "All of the new evidence we have reviewed is also consistent with a Lilliput Effect affecting birds across the K-Pg mass extinction." Paleontologists have dubbed this phenomenon the "Lilliput Effect" — a nod to the classic tale Gulliver's Travels.
"Smaller birds tend to have faster metabolic rates and shorter generation times," Field explains. "Our hypothesis is that these important biological characters, which affect the rate of DNA evolution, may have been influenced by the K-Pg event."
