![]() The fact the we lack all the evidence doesn’t automatically equate to there being noevidence, of course. Over time, gaps in concrete knowledge about the absolute origin of birds has led to two factions – those who believe Birds Are Not Dinosaurs – BAND – and the Birds Are Dinosaurs Movement – BADM. Many believe birds descended from theropods, but there are some things about this that niggle – in evolutionary terms it is relatively unknown for a creature to re-elongate short limbs: if the short-forelimbs of theropods eventually became wings, where are the linking fossils to support this? Other issues of discomfort involve the carnivorous toothy factor and the fact that theropods are ridiculously large – where is the proof that birds would lose all remnants of these characteristics? Detractors of the “birds = dinosaurs” theory believe that birds evolved from another group within the same archosaur supergroup.ĭinosaurs can be broken down into two subgroups (simplified version): theropods, short fore-limbed animals such as Tyrannosaurus Rex, and sauropods, the small-headed and extremely long-necked four-legged lumbering beasts, such as the Diplodocus. The word dinosaur simply means “terrible lizard” in Greek this group of creatures were part of a larger group of animals called archosaurs – archo- meaning ruling in this context. A bird’s skeleton retains very little structure after death Winged dinosaurs have been found, but differences in their anatomy to the way modern birds have developed have cast enough doubt in some minds. Our collective evidence about the existence of dinosaurs stems from the discovery of their skeletons: a bird’s skeleton retains very little structure after death and is compressed over time which means we are missing important steps in their development and evolution. Habitat loss and climate change are major drivers of their decline.Courtesy of Durbed, Wikimedia Commons. There may be as many as 15,000 left in the world. The Shoebill is listed as vulnerable by the IUCN. When present they are indicative of a healthy ecosystem. Good indicator species of freshwater ecosystems.They also will prey on lizards, small crocs, other birds and more. ![]()
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