Did Birds Evolve From Dinosaurs

Universe is full of mysteries and evolution is certainly one of them. One such mystery is: Did birds evolve from Dinosaurs? Paleontologists agree that there are evolutionary relationships between birds and dinosaurs. The birds represent a branch of the dinosaur lineage that survived the Cretaceous crisis and radiated into the forms known today. In another scenario, birds and dinosaurs had a common ancestor that gave rise to both groups.

A huge variety of ancient bird types have come and gone and evolved to give us the 9000 different species we know today. Many scientists are convinced that birds evolved from the dinosaurs. Numerous finds in recent years have seemed to support the hypothesis that birds descended from two-legged, running dinosaurs

The bird, Liaoningornis, did not look like a dinosaur bird at all. It had a breastbone similar to modern birds, with massive flight muscles that enabled longer flights. Feduccia and Martin claim that flight is most likely to have started from a tree-climbing (arboreal) ancestor but that all the proposed dinosaurian ancestors were ground-dwellers (cursorial). This is the "trees-down" versus the "ground-up" debate and the trees-downers do have a point. Birds-Are-Dinosaurs crowd argue that an unknown dinosaurian bird-ancestor could have been arboreal or that birds evolved flight from the ground up by chasing and leaping after insects (Willis, 2003). According to Gilbert (1998) there are significant morphological differences between the dinosaurs and birds. While there is no disputing that Archaeopteryx had feathers (they are clearly preserved in two of the seven known specimens, and feathers are a distinctly avian feature), the skeleton of Archaeopteryx is distinctly non-bird-like with a long bony tail, teeth instead of a beak, and claws on the wings. While the Birds-Are-Dinosaurs supporters emphasize the similarities this skeleton has to dinosaurs, the theory’s detractors contend that the skeleton has too many bird-like features to make it a coelurosaur. For instance, Archaeopterix has a wishbone (furcula) and bird-like feet. This means that it is not merely a

Cladists argue that differences between organisms don't matter; it's the similarities that count. Evolution dictates that organisms will change through time so it's only the features that remain the same that will carry useful information about their origins.

In a nutshell, the majority of palaeontologists working on the ancestry of birds agree that dinosaurs, particularly small theropods, are the grandparents of present-day parrots, partridges and pigeons. There are some detractors to this emerging orthodoxy but the dino-bird theory is supported by both cladistics methodology and a rapidly growing collection of primitive birds and advanced meat-eating dinosaurs (Willis, 2003). One thing is certain as birds continue to adapt to habitats and changing conditions that such a versatile creature will always be with