MEANING: Near bird
PERIOD: Late Jurassic
CONTINENT: Asia
Anchiornis is a small paravian dinosaur from the Late Jurassic of China. It could grow to around 60 cm in body length with a wingspan nearly as wide, and weighed about 1 kg. In addition to the front wings, Anchiornis had long feathers on the hind legs, leading many scientists to call it a four-winged dinosaur. Thanks to an extremely well-preserved specimen, scientists have been able to study the melanosomes in the feathers and determine the full body colors and patterns of Anchiornis. The body was mainly black and gray and the primary feathers were white with black tips and patterns. It also sported a red crest on the top of its head.
Anchiornis is from the Jurassic. The Jurassic is a geologic period that spanned from the end of the Triassic, 201 million y ears ago, to the beginning of the Cretaceous, 145 million years ago. It is the middle period of the Mesozoic Era. The start of the Jurassic was marked by the major Triassic-Jurassic extinction event. The end, however, has no clear boundary with the Cretaceous. By the beginning of the Jurassic, Pangea had begun rifting into two landmasses: Laurasia and Gondwana, and the climate was warm with no ice caps. Life on land was dominated by dinosaurs, and the first birds appeared, evolving from a branch of theropods. The oceans were inhabited by marine reptiles, while pterosaurs were the dominant flying vertebrates.
Anchiornis is a Paravian. The evolution of birds began in the Jurassic Period, with the earliest birds derived from a clade of theropod dinosaurs named Paraves. The Archaeopteryx has famously been known as the first example of a bird for over a century, and this concept has been fine-tuned as better understanding of evolution has developed in recent decades.
Like other theropods, all paravians are bipedal, walking on their two hind legs. Most of the earliest groups were carnivorous, though some smaller species are known to have been omnivores. Paravians generally have long, winged forelimbs, though these have become smaller in many flightless species. The wings usually bore three large, flexible, clawed fingers in early forms. Over time, the fingers became fused and stiffened in some lineages, and the claws reduced or lost. An increasingly asymmetric wrist joint allowed the forelimbs to elongate and an elaboration of their plumage eventually allowed the evolution of flapping flight possible.