Thursday, March 10, 2016

Blooming of March Spring. The Saga of the Triassic.

Strange beast
One of the oddest creatures that shared the planet with early dinosaurs was placerias. It must have looked like a cross between a hog, a cow and a turtle. Placerias was a large, herding herbivore with a horny beak and a pair of downward-pointing tusks. It was a dicynodont ("two dog-teeth") - a group of animals that shared common ancestors (the synapsids) with modern mammals. Palaeontologists believe placerias ate low-growing plants, as well as using its tusks and beak to grub for roots and tubers.
The dicynodonts were very successful before they died out. Early Triassic dicynodont remains have been found in South Africa, India, China, Russia, Australia and Antarctica.

Slim and dangerous
One of the first true dinosaurs was coelophysis ("hollow form"), a carnivorous, bipedal predator that emerged in the late Triassic, between 225 and 220 MYA. Hollow-boned coelophysis grew up to 3 metres in length, weighed around 27kg and probably fed on smaller reptiles and amphibians. It had curved claws on its hands and a slim head crammed full of very sharp teeth.
Some experts have suggested that coelophysis could bring down bigger animals by taking slashing bites out of their legs or sides. Fossil coelophysis skeletons have been found in the same locations, so it's possible that these dinosaurs may have herded, although there's no firm evidence that they hunted in packs. It is also believed that coelophysis was a cannibal that preyed upon its own young during lean times.

First of the giants
Around 210 MYA, a new type of dinosaur emerged - the giant herbivore, plateosaurus ("flat lizard"). Weighing around 3 tonnes and growing up to 7 metres, plateosarus was a forerunner of the huge Jurassic dinosaurs. It had a long, powerful tail and a set of coarsely serrated teeth for chewing tough vegetation. plateosaurus also had a large, curved claw on its thumb. We're not sure whether this was used for food collection or defence.
Large numbers of plateosaurus skeletons have been found in the same location, suggesting they may have herded. Alternatively, instinct drew them to the same place to die.

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