A bird with a body length of 30–33 cm, weighing 145–218 g in males and 138–223 g in females [3] . This is a slender cowgirl with long legs and toes. The plumage is brown in color, only the throat is white. The beak is straight, dark. In males, the base of the beak is dark red, in females - pink.
Lives in various wetlands, bushes, subtropical and tropical rainforests. It feeds on mollusks, crustaceans, other small animals and insects. Keeps alone, in the breeding season - in pairs. Breeds during the rainy season. A nest is building on the earth among the grass.
The species is common in Madagascar and Seychelles . On the atoll Aldabra subspecies D. c. aldabranus (some scientists distinguish it in a separate form [4] ). Subspecies D. c. abbotti , who lived on the island of Assampshen , became extinct at the beginning of the 20th century due to introduced predators . The species also disappeared from the island of Mauritius , but successfully settled the neighboring island of Picard.
The last surviving subspecies of flightless birds of the shepherd’s family, the white-necked shepherd, had previously died out on the islands of the Indian Ocean , but had risen from the dead, thanks to a rare process called “iterative evolution ”. Scientists from Portsmouth University and the Natural History Museum of Great Britain found that in two cases separated by tens of thousands of years, this species was able to successfully colonize an isolated atoll called Aldabra, and in both cases became a flightless species. The last surviving colony of flightless birds of the species Dryolimnas cuvieri still lives on the island.
A chicken-sized bird lives today in Madagascar in the southwestern Indian Ocean. The species was a permanent colonizer of isolated islands and was often subject to population explosions, so it migrated in large flocks from Madagascar. They spread north or south, where many of the birds drowned in the open ocean. Migrants to the west ended up in Africa , where predators ate them. The eastward orientation turned out to be the most successful, as the birds settled on numerous ocean islands such as Mauritius , Reunion and Aldabra, the last of which is a ring coral atoll, formed about 400,000 years ago.
Since there were no predators on the atoll, but there was a lot of food, the birds developed so that they lost their ability to fly. When Aldabra disappeared under water during a major flood about 136,000 years ago, all flora and fauna, including the bird population, were destroyed.
Researchers examined fossils dating to about 100,000 years ago and compared them to the bones of birds discovered before the flood. They saw a similarity on the basis of winglessness. This means that one species that previously inhabits Madagascar gave rise to the development of two different species of non-flying birds on Aldabra after several thousand years. Scientists emphasize that this is the first case of observing an extremely rare phenomenon - iterative evolution - in nature [5] (the repeated evolution of similar or parallel species having the same ancestor, but at different times) seen in this form, which is a kind of discovery in bird observations [6] [7] [8] .
