Was the extinction of proboscideans due to humans or climate change? The most extreme example would be the wooly mammoth, which had thick, shaggy hair and large tusks for retrieving vegetation hidden under thick snow. Only the most ecologically versatile proboscideans survived. This richness of giant herbivores was unlike anything in today's ecosystems.īut from about six million years ago, the diversity in proboscideans started to decrease following the harsh cooling of Earth. This resulted in a variety of forms, with three to four different proboscidean species coexisting in one space. Provided with new challenges and habitats, proboscideans that expanded from their range in Africa evolved 25 times faster than the cousins they left behind. Over the past 20 million years, the global climate changed frequently and dramatically. This was via the land bridge which sporadically connected Siberia to Alaska and is now submerged under the Bering Sea. Once the Afro-Arabian Plate collided into the vast Eurasian landmass, an important migratory corridor was formed, which allowed the species to explore new habitats in Eurasia and then into North America. How and why did proboscideans evolve so rapidly?Įarly proboscideans that lived in Africa were slow-evolving with little diversification. The research culminated into the most detailed analysis to date of the rise and fall of elephants and their cousins. Steven says, 'Some of the most significant clues for gauging the epic proboscidean story were found right here in the collections of the Natural History Museum, one of the very few institutions in the world housing fossil specimens representative of all eight evolutionary directions.' Using fossil collections from museums around the world, they studied the evolutionary adaptations of 185 species over 60 million years of existence. Steven, along with an international team of paleobiologists explored why and how proboscideans changed so much over millions of years. They all bore little resemblance to elephants.' A few species got as big as a hippo, yet these lineages were evolutionary dead ends. 'Most proboscideans over this time were nondescript herbivores ranging from the size of a pug to that of a boar. Steven Zhang, Honorary Research Associate at the University of Bristol, says, 'Remarkably, only two groups of proboscideans evolved during the first half of the proboscidean evolution, which lasted around 30 million years. In fact, some of the earlier species, such as the Eritherium which lived in Morocco, were as small as foxes and lacked a trunk. Unlike the three endangered species of elephants we know today, not all proboscideans were giants, nor did they look anything like their cousins. Proboscideans were a diverse and widespread group of herbivores that first appeared in Africa about 60 million years ago. Like all other rhinoceros', Coelodonta's horn was actually composed of keratin, the same substance that makes up human hair, instead of the resilient ivory associated with elephants.Ĭoelodonta was named in 1799 by Johann Friedrich Blumenbach and its name means "hollow tooth".Elephants - the largest land animals alive today - are the only remaining species of the family Elephantidae, which belongs to an ancient order of Proboscidea. Trailing from the hump of its shoulders to the start of its head, Coelodonta had a crop of fur not unlike a mohawk which varied in appearance from species to species. With a substantially larger pair of horns than most rhinoceros', Coelodonta definitely held a bold presence in the frozen wastes of the Ice Age. Unlike many of its relatives, Coelodonta lived in the cold boreal environments of the far North, necessitating its furry overcoat. Similar to the extant species of African Rhinoceros', Coelodonta is a large herbivorous mammal uniquely covered with a thick layer of fur.
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