Upcoming Events
- No events.
-
From the Gallery
Links
-
Contact
Question of the Day
Question:
"Dr. Hal, does anybody know what dinosaurs would taste like if you ate one?"Answer:
My boy, in all probability you know, and will taste this delicacy again within a week's time. That's right: the humble Thanksgiving turkey is classified by modern Science as a dinosaur. A re-examination of the field of Taxonomy, coupled with the latest fossil findings, leads to this inexorable conclusion; now there is a call to abolish the class Aves and fold this taxon into the Dinosauria. Although there are some hold-outs, few dispute the propriety of the claim. Just look at that plucked thing on the dinner table. It agrees with dinosaur anatomy in an overwhelming number of significant points.
The fossil record of birds is not extensive: the light, hollow bones of birds are not likely to survive the folding, mutilating and stapling of the geological process. However, a growing number of unusually well-preserved fossil birds are contributing much to our understanding of bird evolution. The oldest known fossil unambiguously identified as a bird is still the dinosaur-like Archaeopteryx, from the Solnhofen Limestone of the Upper Jurassic of Germany. Opinion has varied over whether this is a bird or a little dinosaur. The general consensus now is that it is both. However, it was not the only bird of the time. Very recently, another bird of almost the same age was discovered in northeastern China, and named Confuciusornis, resembling Archaeopteryx in having wing claws, but unlike Archaeopteryx and like modern birds, lacking teeth.
Other birds belonging to various lineages have been found in Cretaceous deposits of Asia, Europe, and North and South America. Our knowledge of the Mesozoic fossil record of birds is rapidly growing: the number of known fossil birds from the Mesozoic doubled between 1990 and 1995. And the picture of bird evolution is constantly changing as more fossils are found; scientists still doggedly debate the classification of some of these. Prominent and well-known Cretaceous bird taxa included the Enantiornithes, a fairly diverse group of birds, mostly flying forms; Hesperornithiformes, toothed birds which were mostly flightless swimmers; and even weirder, the Ichthyornithiformes, toothed flying birds that probably fed on fish. Though these types are extinct today, by the close of the Cretaceous, representatives of several modern bird varieties were sharing the skies with these extinct birds. A birdwatcher 65 million years ago could have se en relatives of today's loons, geese and ducks, albatrosses and petrels, gulls and shorebirds, and possibly forms of other familiar birds as well. For example, there was the terrifying six-foot tall owl known as Brachycneme draculae, recently unearthed in the Carpathian mountains in present-day Transylvania. The closely related Hepasteornis was nearly as large. Although a warm sea covered most of this area in the latter part of the Secondary, this colossal owl lived on a group of islands which were covered with lush forests. Here dwelt a race of pigmy dinosaurs who quivered in terror as they hid under the sheltering branches from this night-flying bird-monster; their fossils have been dug up in the last seventy-five years, in the area around Hätszeg...
Modern birds continued to diversify through the Cenozoic, where the bird fossil record consists largely of isolated bones (although some nearly complete skeletons have been recovered from certain localities). Suffice it to say that by the early Oligocene, 35 million years ago, most of the bird orders that we recognize today had appeared. Our hypothetical birdwatcher could have added to her list relatives of today's fowls, doves, parrots, penguins, crows, owls, and songbirds, to name a few. Were she birdwatching in South America, however, she would have had to steer clear of the phororhachids -- flightless, fast-running predatory birds, some nearly three meters tall, armed with enormous beaks and claws. These "terror-birds" were the dominant South American land carnivores for much of the Cenozoic. Recently, phororhachid bones have been found as far North as Florida, suggesting that phororhachids were not confined to South America. In North America and Europe, in the Eocene, members of a different family of birds, the Diatrymidae, resembled the phororhachids and probably would peck you to death just as quickly. Both of these bird families had reduced wings and could not fly, and looked something like living ratite birds -- ostriches, emus, rheas, and so on. However, phororhachids and diatryimids were not closely related to the ratites, but were closer to living cranes, rails, and coots. I hope this is clear.
Askdrhal.com by
Jascha Ephraim,
proudly powered by
WordPress
RSS