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The basal bird Archaeopteryx, from the Jurassic, is well known as one of the first "missing links" to be found in support of evolution in the late 19th century. Though it is not considered a direct ancestor of modern birds, it gives a fair representation of how flight evolved and how the very first bird might have looked.
A turning point came in the early twentieth century with the writings of Gerhard Heilmann of Denmark.An artist by trade, Heilmann had a scholarly interest in birds and from 1913 to 1916, expanding on earlier work by Othenio Abel, [12] published the results of his research in several parts, dealing with the anatomy, embryology, behavior, paleontology, and evolution of birds. [13]
Evolution of the creodonts, an important group of meat-eating (carnivorous) mammals. 62 Ma Evolution of the first penguins. 60 Ma Diversification of large, flightless birds. Earliest true primates, [who?] along with the first semelid bivalves, edentate, carnivoran and lipotyphlan mammals, and owls.
The WAIR hypothesis, a version of the "cursorial model" of the evolution of avian flight, in which birds' wings originated from forelimb modifications that provided downforce, enabling the proto-birds to run up extremely steep slopes such as the trunks of trees, was prompted by observation of young chukar chicks, and proposes that wings ...
Birds have wings whose development varies according to species; the only known groups without wings are the extinct moa and elephant birds. Wings, which are modified forelimbs, gave birds the ability to fly, although further evolution has led to the loss of flight in some birds, including ratites, penguins, and diverse endemic island species ...
Archaeopteryx continues to play an important part in scientific debates about the origin and evolution of birds. Some scientists see it as a semi-arboreal climbing animal, following the idea that birds evolved from tree-dwelling gliders (the "trees down" hypothesis for the evolution of flight proposed by O. C. Marsh).
With the unearthing of several well preserved early bird fossils in the last decades of the 20th century and early 21st century, our knowledge of the evolution of birds has increased dramatically. [1] The evolution of the modern avian traits such as the compact body, clawless wing and the alula are now
The first person to have a severe case of H5N1 bird flu in the United States has died, according to the Louisiana Department of Health. This is the first human death from bird flu in the US. The ...