Sahni, who was in Indore for launch workshop of National Dinosaur Fossils Park at Bagh in Dhar district of Madhya Pradesh, said it is believed that dinosaurs are the prehistoric ancestors of modern day birds.
Sahni, however, said there is nothing unusual about it, evolution is natural phenomena. Human have evolve from apes, similarly feathered dinosaurs slowly evolve into birds. He added that dinosaurs were just a wildlife of past.
During the Jurassic period one of the earliest known birds lived and breathed next to dinosaurs. This 150-million year old bird is called Archeopteryx. It is believed to be the "missing link" between birds and dinosaurs.
Elaborating further, Sahni said average mean temperature of earth at present is around 15 degree Celsius and average mean temperature of earth at the time dinosaurs were found was around 24 to 26 degree Celsius. At that time environment of earth was very hot and dinosaurs were cold blooded animals, over the period of time temperature of earth witness lots of fluctuations and in order to insulate there body from external temperature small dinosaurs develops feathers. Slowly there feathers evolve with the time, as selective evolution theory says parts of organ of the living creature grows more if the use of that particular organ or part is more.
Feathered dinosaurs use to use their feather for catching insects for eating, with the changing geological events on earth which forces extinction of dinosaurs feathered dinosaurs evolve into birds.
Fossils of Archeopteryx, called Jurassic bird shared many traits found in small dinosaurs and modern day birds. The Archeopteryx had a jaw filled with sharp teeth. It also had a hyper extendible claw on its foot, known as a "killing claw." Covered in feathers, similar to those that covered dinosaurs, the Archeopteryx had flight feathers; a trait found in birds, but not dinosaurs. This early bird had a long bony tail common in dinosaurs, but a trait modern birds lack. Birds today only have a tiny stub in place of a tail called a pygostyle.
Coming to dinosaur fossils found in MP, Sahni said fossils found in Narmada valley is of great importance not nationally but internationally. The first fossil of dinosaur was found in 1828 by William Sleeman, even before the word dinosaur was coined. The word dinosaur was coined in 1848 on the fossils found by Sleeman. Beside first dinosaur fossils recorded in Asia was from Jabalpur and it is the place were dinosaurs fossils of three generations are found including the youngest one, considered to be last dinosaurs on earth.
The dinosaurs were extinct because of collapse of food web cycle possible due to volcanic eruption or asteroid hit.
A plant fossils expert, Dr Mohan Bande said Narmada valley has rich collection of fossils including plant fossils which can tell us about the flora, vegetation and environment of the time when dinosaurs were found.
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