![]() ![]() This is not good, since low genetic diversity and high inbreeding may increase the risk of extinction in the present-day species.” “This suggests that recent population declines caused by hunting and habitat destruction have had an impact on the genomes. “However, we also find that present-day rhinos have lower genetic diversity, and higher levels of inbreeding, compared to our historical and prehistoric rhinoceros genomes,” he followed. This may explain why rhinos have persisted for so long despite their apparent low levels of genetic diversity within their populations.ĭalén says that the findings are “partly good news, and partly not.” For one, their findings reveal that despite low genetic diversity, rhinos have maintained relatively healthy populations. This, Westbury continued, is apparently consistent with the observed notion that rhinos apparently lack what are called deleterious mutations in their genome, or mutations that would otherwise make the rhino susceptible to certain diseases and disorders that would have impacted their survival. Mick Westbury, from the University of Copenhagen in Denmark, added that “continuously low population sizes may indicate that rhinoceroses in general are adapted to low levels of diversity.” Westbury noted that the five extant and three extinct species they analyzed experienced a constant decrease in population size over the last 2 million years. To some extent, this means that the low genetic diversity we see in present-day rhinos, which are all endangered, is partly a consequence of their biology.” Said Love Dalén, from the Centre for Palaeogenetics at the Swedish Museum of Natural History: “We can now show that the main branch in the rhinoceroses’ tree of life is among geographic regions Africa versus Eurasia, and not between the rhinos that have one versus two horns.” (Both the Indian and Javan rhinoceros have two horns the other three surviving species have only one.) Dalén also added that “all rhinoceroses-even the extinct ones-have comparatively low genetic diversity. For starters, the African and Eurasian lineages of rhinos split about 16 million years ago. The team’s findings reveal new insights on the endangered family of animals. ![]() (National Museum of Nature and Science/Wikimedia Commons, 2012) Their study was published in the journal Cell.Ī skeletal cast of Paraceratherium transouralicum at Tokyo’s National Museum of Nature and Science. Now, an international team of researchers has opted to use genetic analysis to finally get to the root of how these animals-the five extant and other three extinct species-are all related. Aside from this, most of their rhino relatives died out right before the Pleistocene epoch around 2.5 million years ago fossils of rhinos and rhino relatives have been found scattered across the Earth for decades now, including the famous 5-m (16.4-ft.) high and 10-m (32.8-ft.) long Paraceratherium, known to be one of the largest land mammals to ever walk the Earth despite this, efforts to truly understand just how these distant rhino relatives are related had been sporadic at best. As one will notice, these giants of the forest are separated by vast tracts of continental land, and even oceans. One such question that, up until recently, has been difficult to answer is the relationship between these five surviving species of rhinos. As such, it has proven difficult for scientists to study these animals for research finding them undisturbed in the wild ends up being quite an effort, not to mention the actual research work that needs to be done to find what you need to find on them. These beautiful animals have sadly been regulars on the endangered species list for decades now, as humans have been overhunting these beasts to near-extinction for their horns, which some cultures use as part of their traditional medicine. ![]() Four of the five remaining species of rhinos are in the picture above: (clockwise from upper left) the white, Sumatran, Indian, and black rhinoceros. ![]()
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