May 4, 2011
What Exactly Was The Australian Thylacine?
The thylacine had the head and body of a dog, but its striped coat resembled a cat and it carried its young in a pouch like a kangaroo. These enigmatic, iconic creatures of Australia and Tasmania have been given conflicting names such as the "marsupial wolf" and the "Tasmanian tiger."
Researchers at Brown University may have discovered the answer as to what type of creature the extinct thylacine was.
The thylacine was able to rotate its arm so that the palm faced upwards, similar to a cat, reports BBC News. This allowed the animal to increase the amount of arm and paw movement to help the Tasmanian tiger subdue its prey after an ambush.
Borja Figueirido, a postdoctoral researcher at Brown University and lead author says, "We provide quantitative support to the suspicions of earlier researchers that the thylacine was not a pursuit predator. Although there is no doubt that the thylacine diet was similar to that of living wolves, we find no compelling evidence that they hunted similarly."
The research, published in Biology Letters, shows that the extinct thylacine was a "solitary, ambush-style predator, with hunting skills that are unlike those of wolves or dog-like species that hunt in packs and pursue their prey over distances.
Dog-like animals such as wolves and dingos have a more restrictive arm-hand movement, which has their paws fixed at a palm-down position; therefore, showing that their hunting strategy is to pursue a prey in packs rather than by ambush.
But this in not all-encompassing, since cats like the cheetah use speed to catch its meal and dog-like foxes rely on ambushing their prey.
Christine Janis, co-author and professor of biology in the Department of Ecology and Evolutionary Biology at Brown, says that the thylacine's hunting method seems to be a unique mix.
"I don't think there's anything like it around today. It's sort of like a cat-like fox."
After millions of years of existence in Australia, the Tasmanian tiger ended its species with the final thylacine named Benjamin, who died in Hobart Zoo, Tasmania in 1936.
The extinction of the thylacines probably began about 40,000 years ago when humans started to settle in Australia, and the dingo, a small, dog-like creature, was introduced into the environment around 4,000 years ago.
Humans most likely disrupted thylacine habitat and probably even its food sources, but the dingo's role in the disappearance of the Tasmanian tiger is still debatable, say researchers, since the hunting habits of these two animals are different from one another.
"Dingoes were more like the final straw [to the Tasmanian tigers' demise in continental Australia]," Janis says, "Because they weren't in the same niche. It's not just that a dingo was a placental version of a thylacine."
Eventually, the dingo-free island of Tasmania became the thylacines final living environment, where there was an effort to eradicate the animals in the 19th and 20th centuries.
Image 1: Though highly similar in their skull anatomy, specialized for a carnivorous diet, the thylacine, front, and the dingo very likely had different hunting styles. Researchers analyzing skeletons of the forelimbs found important differences. Credit: Carl Buell
Image 2: The elbow joint of the thylacine and the modern tiger, top, is wider and more rectangular than the dog-like wolf and fox, bottom, which are more toward the square. This suggests different styles of catching and subduing prey, cat-like or dog-like. Credit: Borja Figueirido (specimens from the American Museum of Natural History)
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