How the Galapagos cormorant lost its ability to fly

The flightless Galapagos cormorant is one of a diverse array of animals that live on the Galapagos Islands, which piqued Charles Darwin ’s scientific curiosity in the 1830s. He hypothesized that altered evolutionary pressures may have contributed to the loss of the ability to fly in birds like the Galapagos cormorant.In a new study unraveling the cormorant ’s DNA, UCLA scientists discovered genetic changes that transpired during the past 2 million years and contributed to the bird’s inability to fly. Interestingly, when these same genes go awry in humans, they cause bone-development disorders called skeletalciliopathies.Published today in the journal Science, the findings shed light on the genetic mechanisms underlying the evolution of limb size and could eventually lead to new treatments for people with skeletal ciliopathies.“A number of these iconic, salient evolutionary changes occurred in the Galapagos,” said senior authorLeonid Kruglyak, professor of human genetics at the David Geffen School of Medicine at UCLA. “Darwin, just by looking at these changes, inferred the process of evolution by natural selection. We now have sophisticated genetic tools to reexamine these classic examples and uncover what happened at the molecular level.”The Galapagos cormorant, with its short, scraggly wings, is the only one of 40 cormorant species that cannot fly. It is also the largest of the cormorants, and a strong swimmer that dives for its meals of fish.Researchers, inclu...
Source: UCLA Newsroom: Health Sciences - Category: Universities & Medical Training Source Type: news