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http://www.bbc.com/earth/story/20150107-...arge-rival
 ~Talk about having a big personality.Scientists have spotted and filmed a dwarf male Asian elephant wandering the forests of Sri Lanka.The elephant has a normal-sized head and body, but very short and stubby legs.Thought to be the first of his kind ever recorded, the elephant surprised the researchers further by engaging in his very own rumble in the jungle.In a series of extraordinary encounters in the Uda Walawe National Park, the elephant, nicknamed the Walawe Dwarf by observers, waged an all-out battle against a full-sized male elephant.What’s more, he appeared to be winning.
   ~Elephant researcher Shermin de Silva, Director of the Uda Walawe Elephant Research Project, and her colleagues, reported their encounters with the dwarf in the journal BMC Research Notes.Barely two metres tall, the Walawe Dwarf, according to the researchers, is the first confirmed case of disproportionate dwarfism in a fully-grown Asian elephant (Elephas maximus maximus) in the wild. His condition is most likely caused by a genetic mutation resulting in disproportionately short limbs.
 ~Researchers first spotted the Walawe Dwarf in 2012, an encounter that lasted for a fleeting moment. The dwarf came out from behind a bush, trumpeted, ran across the road, and then disappeared.“At the time, I didn't even notice it was a dwarf,” Nilmini Jayasena from the University of Peradeniya in Sri Lanka, who saw the animal in 2012, told BBC Earth. “It was a quick glimpse, mostly through the camera view finder.” A year later, Jayasena compared the elephant’s photographs with those in de Silva’s database and confirmed that the individual had indeed been the dwarf.
  ~The following year, in July 2013, another team of scientists spotted the dwarf sparring with a young-adult male elephant in the forest.de Silva’s team, too, saw the animal a few days later, walking down a forest road, while the fights with the much larger rival were recorded in June 2014. In both the 2013 and 2014 encounters, the researchers observed that the dwarf had dark streaks on the sides of his head, resulting from his temporal gland secretions. These secretions are indicative of a physiological state called ‘musth’.Male elephants in musth, characterised by a surge in the levels of their sex hormone testosterone, show heightened sexual excitement, and increased aggression towards other male elephants. Since only sexually mature elephants periodically go into musth, researchers estimate that the Walawe Dwarf is likely to be over 20 years old.
     ~“He is probably 30-35 years old judging by the development of his secondary sexual characteristics and the extent of musth,” Prithiviraj Fernando, scientist at the Centre for Conservation and Research in Sri Lanka, who reported his team’s observations of the dwarf elephant in 2013, told BBC Earth.When de Silva’s team saw the Walawe Dwarf challenging the big bull in 2014, they were taken aback by how the dwarf was not only the more aggressive of the two, but he also seemed to be winning the match. Despite being shorter, the dwarf and the bull may have been evenly matched in terms of weight, de Silva said.
    
~“The dwarf could very effectively charge his opponent head on whereas the taller individual had to stoop down awkwardly,” she said. “The taller bull could be more easily knocked off balance, while the dwarf’s low center of gravity made it more difficult. So it really seems the mismatch was actually working in favour of the dwarf so long as his opponent was of comparable weight.”
 ~de Silva’s team did not observe the outcome of the battle. But two days later, they saw the Walawe Dwarf at the same location, resting under a tree with a group of females and calves.Since female elephants tend to be much smaller than adult males, Fernando said, the Walawe Dwarf may also be able to mate, especially with a smaller female.The Walawe Dwarf’s success in the wild, despite his disproportionate stature, could be because elephants don’t have predators, he added. “However, in almost all species such a condition would be a death warrant in the wild as most species are prey or predators, and would be unable to get away or catch prey respectively.”According to the researchers, there is no record of the Walawe Dwarf in the Uda Walawe National Park before 2012. This is probably because elephants move over large areas, floating in and out of the national park. The dwarf, too, like most other bulls, probably spends most of his time ranging in forests and croplands outside the protected areas, de Silva said.
  ~Digging through historical photographs of captive elephants, de Silva’s team found that a young tusker, captured from the wild in Sri Lanka in 1933, could also fit the bill of a dwarf based on his recorded measurements. But unlike the Walawe Dwarf, the tusker’s body and limbs were proportionate, making him a possible proportionate dwarf. The tusker was taller than the Walawe Dwarf.Small elephants also occur in the island of Borneo. But these endangered Borneo pygmy elephants (Elephas maximus borneensis), are only slightly shorter than the mainland Asian elephants, and are not dwarfs.
 ~During the Pleistocene Period, however, dwarf elephants did once populate the Mediterranean Islands. “However, all such instances refer to individuals that were simply small (called proportionate dwarfism),” Fernando said. “The elephant observed in Uda Walawe Sri Lanka is the first confirmed record of an individual with 'disproportionate dwarfism'.”Follow BBC Earth on twitter.

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