Giant tortoises are Extinct Appears Back

After 150 years thought to be extinct , a kind of giant Galapagos turtles going back " live " , the scientists reported on Monday ( 9/1/2012 ) .

The researchers found that the missing species - called Elephantopus chelonoidis - by analyzing the genomes of other closely related species , Chelonoidis becki . The second type is live on Isabela Island , the largest island in the Galapagos Islands , the Pacific Ocean . The island is located approximately 322 kilometers from Floreana Island , where Chelonoidis elephantopus was last seen before disappearing , presumably due to hunting by whalers , some 150 years ago .

The second species of giant tortoises that live on the Galapagos Islands have different shaped shells . C shell elephantopus of Floreana Island saddle-shaped while tortoises on other islands , including C. becki , had domed -shaped shells . The giant tortoise can reach weights almost 408 pounds and a length of almost 1.8 meters .

The discovery of mixed ancestry

In 2008, the researchers found that some C becki tortoise has a shell shaped more like a saddle than a dome . They then believe that this is a mixture of offspring ( hybrids ) of mating between two different species . They then took samples for genetic analysis of 1,669 large turtle from the island, or about 20 percent of the total population . As a result, found some pieces of C. elephantopus genome in the population .

Using a special computer model , they analyzed the genes when it entered into the population . Clearly , the intermingling of genes that occurs when a C. elephantopus mated with C. becki - and this is indirect evidence that at that time there was a turtle type C. elephantopus live .

They found that 84 of the tortoises had genetic indicators that one of them is C. elephantopus parent , and 30 of them aged less than 15 years . Given the age of the turtle can reach 100 years old , the researchers say is most likely holding the manifold C. elephantopus are still alive .

" This is the first time living species found again by genetic trace left in the genomes of their mixed ancestry , " said researcher Ryan Garrick from Yale University , and is now an assistant professor at the University of Mississippi . " These findings give new breath of life to conservation efforts for these animals . "

Based on the genetic differences between the mulatto turtles , the researchers estimate that at least 38 C. elephantopus left tail of mixed ancestry in the Galapagos Islands , and some may still be alive .

Turning extinct

If the researchers can find the population , they could capture some to be a parent in breeding programs so that the species is " alive " again . In a paper published January 9, 2012 in the journal Current Biology , the researchers write even a possibility " awaken " the species from the genetic snippets found in turtle - kuran type C becki .

" If we can find these animals , we can restore them to their home island . 's Important because the animals are a key species that play an important role in maintaining the ecological integrity of there , " said study researcher Gisella Caccone of Yale University .

In an interesting discussion , the researchers are still wondering how a giant tortoise can move from Floreana Island to Isabela . They suspect the animals may be brought to Isabela as food and then thrown overboard or left on the beach .