Thursday, January 12, 2017

The woolly mammoth reborn?

The woolly mammoth one of the closest ancestor of todays elephants.
Woolly mammoths, which had significant populations in the northern hemisphere during the pre-glacial period, went extinct due to hunting and the climate change.  According to experts, warmer atmosphere due to the end of the ice age shrank the habitat of these giants. And although the creature went extinct thousands of years ago, scientists are now trying to artificially create this elephant-like mammal through cloning. A team of researchers at Harvard University believe they could bring back the woolly mammoth from extinction within the next two years. 
They believe that advances in gene cloning science will allow them to make what just a few years ago would have been considered an impossibility that is to bring a species back from extinction. They have been studying the DNA from frozen mammoths found preserved in the Arctic. Specifically, they’ve been looking for genes that separated them from elephants.
Mammoth DNA was obtained from Siberian permafrost specimens. The DNA helped them to recreate 14 genes of the mammoth after rigorous analysis. Sophisticated technique of ‘clustered regularly interspaced short palindromic repeat ‘allowed them to edit DNA in such a way that modern DNA was manipulated to replace prehistoric genes.  The Asian elephant, closest living species to mammoth as per the gene map was chosen for the experiment.
Elephant cells are fully functioning now with mammoth DNA. Scientists by splicing mammoth DNA into the genome of an elephant embryo believe they can create a mammoth-elephant hybrid. Then grow it  within an artificial womb.The resultant creature would be more like an elephant with a number of mammoth traits than a mammoth. As awesome as playing Ice Age Jurassic Park sounds, there are also other preventative applications for this technology for engineering the DNA of rapidly declining species or those that are becoming too inbred to increase their chance of survival.
Many scientific commentators have termed this process as a part of ‘De-Extinction’.  The scientists at Harvard also believe that the 'new' woolly mammoth can help for the betterment of ecology in Siberia.


Friday, January 6, 2017

Sabre-toothed Tiger

The saber toothed tiger also known as a smilodon any of the extinct catlike carnivores belonging to either the extinct family Nimravidae or the subfamily Machairodontinae of the cat family (Felidae). Named for the pair of elongated bladelike canine teeth in their upper jaw, they are often called sabre-toothed tigers or sabre-toothed lions, although the modern lion and tiger are true cats of the subfamily Felinae.
Smilodon is perhaps one of the most famous prehistoric mammals. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats. Smilodon lived in the Americas during the Pleistocene epoch (2.5 mya–10,000 years ago). Overall, Smilodon was more robustly built than any extant cat, with particularly well-developed forelimbs and exceptionally long upper canine teeth. Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing. S. gracilis was the smallest species at 55 to 100 kg in weight. S. fatalis had a weight of 160 to 280 kg and height of 100 cm. Both of these species are mainly known from North America, but remains from South America have also been attributed to them. S. populator from South America is perhaps the largest known felid at 220 to 400 kg in weight and 120 cm in height. The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns.

The Smilodon hunted large herbivores such as bison and camels, and is thought to have killed its prey by holding it still with its forelimbs and biting it in the neck. Scientists debate whether Smilodon had a social or a solitary lifestyle; analysis of modern predator behaviour as well as of Smilodon's fossil remains lends support to either view. The Smilodon probably lived in closed habitats such as forests and bush, which would have provided cover for ambushing prey. The Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species, but the exact cause is unknown.