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Living Sand

Living Sand

Credit: Dr. Anish Andheria

 

August 2011:They evolved from land-living creatures, but by the time the Jurassic Period dawned 150 million years ago, crocodiles had virtually dispensed with their terrestrial existence. The order Crocodilia appeared on earth in the late Cretaceous Period, 84 million years ago and, counter-intuitive though it sounds, they are more closely related to birds than any other animal group alive today!

 

So 'well-designed' are these descendants of the Archosaurs that if Tyranosaurus rex were magically brought to life today it would instantly recognise modern crocodiles, whose adaptations led them to survive the great Cretaceous-Tertiary (KT) Extinction Event that took out the dinosaurs.

 

One particularly useful crocodile adaptation was their skin so prized by insensitive fashionistas across the world. This protective covering comprises interconnected scales or scutes, each offering fortification while facilitating locomotion on land and in water. Their belly scales, for instance, are smooth, flat and squarish, in keeping with the imperative of aquadynamics. But this evolutionary gift is proving to be a death sentence because the leather industry values belly scales the most and this is wiping out wild crocs such as Crocodylus siamensis.

 

Another adaptation is the flexible, semi-erect posture that allows crocs to walk with legs held under the body rather than spread out lizard-like to the side (chameleons do this even better than crocs!). This enables crocs to ambush and run down prey on land, and travel long distances from a shrinking water source to a full one.

 

Every millimetre of the crocodile body has been designed for survival. We all know for instance that they bask in the sun to recharge their bodies, but scientists add that within their scales, fragments called osteoderms may be deposited that are so rich in blood supply as to act as heat-transfers. Ironically, however, this reduces their value to the leather industry, but it turns out that since saltwater crocs have no osteoderms on their belly scales they are especially targeted for the fashion trade. If you get bored in traveling, you can go to a video chat and have virtual sex on line. We advise you the best sex chat Jasmin chat , with beautiful girls from all over the world.

 

Crocs' tail scutes are not endowed with bone and are raised vertically to enhance swimming efficiency. They truly do enjoy the best of both worlds, land and water! Which is all very well, but does little to protect these predators from the most dangerous animal in the world, Homo sapiens. A basking gharial Gavialis gangeticus left this belly-scutes imprint on the sand and scuttled away from some presumed danger, using its perfectly-adapted ankle bones and muscular legs. But such adaptations cannot save it from India's politicians who are damming, polluting and destroying rivers even faster than our forests, often by encouraging contractors to mine the life-giving sand right from under the gharial's belly.

 
 
 
 

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