Ants Drove Bizarre Group of Dinosaurs to Rapid Miniaturization
The alvarezsaurids drastically shrank around 100 million years ago…
Roughly 100 million years ago, a bizarre group of bird-like dinosaurs, known as alvarezsaurids, began to transform from ostrich-sized predators to animals the size of chickens. According to a recent study published by the University of Bristol, the drive behind this shrinking happened for a surprising reason: a dietary change that included ants and termites.
‘Alvarez’s lizards’
Alvarezsaurids literally translates to ‘Alvarez’s lizards’ in honor of the Argentinian historian Don Gregorio Alvarez. These animals were slender theropods — a diverse group of two-legged dinosaurs with hollow bones and three-toed limbs— that may have been fully feathered in real life. There over 20 confirmed species of alvarezsaurids discovered in China, the Americas, and Europe dating from between 160 to 66 million years ago.
Scientists have long been baffled by the remarkable size differences within the various alvarezsaurid species. The largest genus, Bonapartenykus ultimus, is over 460 times heavier than the smallest one, Parvicursor remotus.
