Dinosaurs never really vanished from EarthAmy Walsh (Author) Published Date : Mar 21, 2016 20:52 IST
Dinosaurs never really vanished from Earth. Most did go extinct, but their evolutionary legacy lives on all around us, in birds. The Museum's new exhibition Dinosaurs Among Us will highlight the unbroken line between the charismatic dinosaurs that dominated the planet for about 170 million years and modern birds, a link that is marked by shared features including feathers, wishbones, enlarged brains, and extremely efficient respiratory systems.
The fossil record of this story and the biological research it inspires much of which is being done by scientists trained or working at the Museum grows richer by the day. So rich, in fact, that the boundary between the animals we call birds and those we traditionally called dinosaurs is practically obsolete. An earlier study also stated that birds are dinosaurs. Ask your average paleontologist who is familiar with the phylogeny of vertebrates and they will probably tell you that yes, birds (avians) are dinosaurs.
If we look back into the history of the issue, it is apparent that many comparative anatomists during the 16th through 19th centuries noticed that birds were very similar to traditional reptiles. In 1860, shortly after the publication of Charles Darwin's influential work On the Origin of Species By Means of Natural Selection, a quarry worker in Germany spotted an unusual fossil in the limestone of the Solnhofen Formation (late Jurassic period). This fossil turned out to be the famous 'London specimen' of Archaeopteryx lithographica.
It was a beautiful example of a transitional form between two vertebrate groups (traditional reptiles and birds); just what Darwin expected would eventually be found. Archaeopteryx, generally accepted as being the oldest known bird, is an important link between birds and other coelurosaurs that has helped to illuminate the evolutionary history (phylogeny) of the group. It is now widely held to be the ancestor of all living birds; this is a common misconception. In fact, recent expeditions in China, Mongolia, Madagascar, Argentina, and elsewhere may uncover dinosaurs that usurp the urvogel status of Archaeopteryx. The exhibit aims to redirect people's thinking of birds by presenting the ancient family tree of the species, while giving a fresh and more accurate view of dinosaurs.
Among the supportive information that solidifies bird and dinosaur link are nesting behaviors, toothless beaks, the similar structures of the brain and bones and even feathers, which are said to have evolved from coarse spikes. MNH paleontologist Mark Norell says it may be because the characters may not look mean enough if presented like they are pigeons. No matter how scarcely depicted the link between birds and dinosaurs are, people should be aware that, one thing is certain, birds are the modern dinosaurs. Dinosaurs never really vanished from Earth, AMNH writes.
In fact, majority did not go extinct and is now living among us in the form of birds. The facts are resoundingly in support of a maniraptoran origin for birds; certainly a theropodan origin at the very least. So when you see a hawk diving to snatch a dove, or an egret darting for fish, or an ostrich dashing across the African savanna, know that you are gaining some insight into what the extinct dinosaurs were like.
Dinosaurs never really vanished from Earth