Amid mounting losses of bird species, National Geographic joined the National Audubon Society, BirdLife International, and the Cornell Lab of Ornithology to declare 2018 the Year of the Bird. For avians, the year’s news was mixed: threats from habitat loss, predators, climate change—but also success stories such as the Asian crested ibis (top), which has rebounded from 12 in the wild in 1981 to more than 500 today. –The Editors
There’s a perception that evolution moves from simple to complex, but bird nests are an exception. Scientists have discovered that bowl-shaped nests (above right) probably evolved from roofed nests (above left) at least four separate times in the history of bird species. A study in the Proceedings of the Royal Society B found that the common ancestor of the passerine group—which encompasses 60 percent of species, including all songbirds—constructed domed nests. Today three-quarters of them build open nests, which are generally easier to fashion but expose the eggs to predators and the elements. This finding, says study author Jordan Price of St. Mary’s College of Maryland, illustrates how a trait’s current prevalence “does not necessarily indicate the order of events during its evolutionary history.” –Nina Strochlic
New Zealand’s naturally playful keas get their funny bones tickled when other parrots make a specific call, Nature reports. The gentle, low warble sends keas into fits of “laughter,” making them the first non-mammal known to show contagious emotion, as rats, chimps, and humans do.