In 1835, the Galapagos Islands shaped the thoughts of a young British naturalist named Charles Darwin, and helped inspire his world-shaking theory of evolution. For that reason, the islands have become something of a Mecca for biologists, who travel there to see the same odd creatures that enthused Darwin.

I like seeing wildlife in general, but some of these creatures have become iconic in evolutionary biology,” says Leonid Kruglyak from the University of California, Los Angeles, who visited the Galapagos in 2012.

There are around 40 species of these birds in the world, and all but one of them can fly. The sole exception lives on the Galapagos, drying its shriveled and tatty wings in the sun.

Kruglyak, as a geneticist, wanted to know why this bird couldn’t take to the skies. He and his own team used blood samples to sequence the cormorant’s genome, looking for mutations that are unique to the flightless one, and that are likely to alter its genes in important ways.

They found a long list of affected genes. Many of these, when mutated in humans, distort the growth of limbs, resulting in extra fingers, missing digits, and other similar conditions. Some of them are also responsible for a group of rare inherited disorders called ciliopathies, where cilia—small hair-like structures on the surface of cells—don’t develop correctly. Cells use cilia to exchange signals and coordinate their growth. If these hairs don’t form correctly, many body parts don’t develop in the usual way. In particular, some people with ciliopathies grow up with short limbs and small ribcages—a striking parallel with the stunted wings and small breastbone of the flightless cormorant.

A decade ago, it would have seemed implausible to ever test if Wright is right. But Kruglyak’s work show just how powerful genetics has become, and how quickly today’s scientists can uncover the evolutionary secrets of intriguing animals.

In five years, I went from seeing this unusual creature in the wild to doing its genome to getting a lot of good clues about what happened [to its wings],” he says.

Read the source article at The Atlantic