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The Proboscidea of the Past
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" Platybelodon was a genus of large herbivorous mammals related to the elephant. It lived during the middle Miocene Epoch in Africa, Asia and the Caucasus."
" Elephant Evolution ?
About 180 million years ago, mammals arose from a reptile-like lineage about the same time as true dinosaurs. About 80 Million years ago, the genetic linage of elephants split from primates. The tree shrew is considered our nearest common ancestor. It is believed that 50-60 million years ago, Moeritheriums, approximately the size of current day pigs, were the roots from which the proboscideans evolved. Based on both morphological and biochemical evidence, it is generally agreed that the manatees, dugongs, and hyraxes are the closest living relatives of today’s elephants. This is incredible given the vast difference in sizes, external appearance and the fact that these animals occupy completely different habitats. The order under which Elephants are classified is the Proboscidea. This means animals with trunks/proboscis. Over the course of evolutionary history, it has been estimated that there have been about 352 species of Probscideans. The creatures of this order have inhabited every continent except Australia and Antarctica. All but two (the African and Asian elephants) have died out. "  
" For a long time, palaeontologists thought that Palaeoloxodon antiquus from Europe had a rather slenderly built skull roof crest; whereas the Indian species Palaeoloxodon namadicus is characterised by an extremely robust skull crest that extends near to the base of the trunk from the top of the skull.
But some Palaeoloxodon skulls, found in Italy and Germany, with almost the same exaggerated skull crest as the Indian form, led a few scientists into suspecting these might all be single species. “Just like modern elephants, Palaeoloxodon went through six sets of teeth in their lifetimes. This means we can tell the age of any individual with confidence by looking at its fossilised teeth,” said Dr. Hanwen Zhang, a paleontologist in the School of Earth Sciences at the University of Bristol and the Department of Earth Sciences at UK’s Natural History Museum. “When we looked at a series of skulls from Italy, Germany and India, we found a consistent pattern: the skull crest developed from being very small, not protruding beyond the forehead in juveniles to being larger and more protruding in young adults, eventually becoming very stout in aged adults.” http://www.sci-news.com/paleontology/palaeoloxodon-evolution-08045.html Art: @rjpalmerartist"
" Fifty thousand years ago, Siberia looked very different from how it does today. Instead of forest and scraggy tundra, the region was blanketed in lush grasslands and fertile soils, and herds of woolly mammoths roamed the open plains.
Then little by little, towards the end of the last Ice Age, their numbers started to diminish. No one really understands why. Some blame human hunting, some climate change, others a bit of both. What we do know is that they disappeared from Siberia 10,000 years ago, then from their final hiding place – a northerly island called Wrangel – just 3,700 years ago. Now Siberia is a massive mammoth graveyard, and it’s estimated that the remains of hundreds of thousands of individual animals lie buried in the permafrost. As our world warms, the permafrost is melting and the remains of these fallen giants are starting to surface. Occasionally, tusks can be spotted poking out of landlocked tundra, but more often than not, they are found in places where the permafrost erodes naturally, like river banks and coastlines. In settlements that turned into ghost towns after the fall of communism, mammoth tusks have offered a lifeline to the region’s indigenous people, who are still legally allowed to collect them. "
" A Columbian mammoth, an African elephant, and an American mastodon (from back to front) next to a 6ft-tall human. Not all mammoths were gigantic, in fact the pygmy mammoth was the size of a large horse.
Illustration by Velizar Simeonovski A mammoth is any species of the extinct elephantid genus Mammuthus, one of the many genera that make up the order of trunked mammals called proboscideans. The various species of mammoth were commonly equipped with long, curved tusks and, in northern species, a covering of long hair. They lived from the Pliocene epoch (from around 5 million years ago) into the Holocene at about 4,000 years ago, and various species existed in Africa, Europe, Asia, and North America. They were members of the family Elephantidae, which also contains the two genera of modern elephants and their ancestors. The earliest known proboscideans, the clade that contains the elephants, existed about 55 million years ago around the Tethys Sea area. The closest relatives of the Proboscidea are the sirenians and the hyraxes. The family Elephantidae is known to have existed six million years ago in Africa, and includes the living elephants and the mammoths. Among many now extinct clades, the mastodon is only a distant relative of the mammoths, and part of the separate Mammutidae family, which diverged 25 million years before the mammoths evolved. " 
At least 200 skeletons have been discovered at the construction-site of an airport north of Mexico City: https://www.latimes.com/world-nation/sto...ction-site
Credit: Marco Ugarte / Associated Press  *This image is copyright of its original author
American mastodon mitochondrial genomes suggest multiple dispersal events in response to Pleistocene climate oscillations
Abstract Pleistocene glacial-interglacial cycles are correlated with dramatic temperature oscillations. Examining how species responded to these natural fluctuations can provide valuable insights into the impacts of present-day anthropogenic climate change. Here we present a phylogeographic study of the extinct American mastodon (Mammut americanum), based on 35 complete mitochondrial genomes. These data reveal the presence of multiple lineages within this species, including two distinct clades from eastern Beringia. Our molecular date estimates suggest that these clades arose at different times, supporting a pattern of repeated northern expansion and local extirpation in response to glacial cycling. Consistent with this hypothesis, we also note lower levels of genetic diversity among northern mastodons than in endemic clades south of the continental ice sheets. The results of our study highlight the complex relationships between population dispersals and climate change, and can provide testable hypotheses for extant species expected to experience substantial biogeographic impacts from rising temperatures.
Incredible artwork of a straight tusked elephant and a red deer by @JulianFriers on twitter. Really captures the scale of this animal twice the size of an African elephant.
 *This image is copyright of its original author
Biggest proboscideans by maximum estimaded weight. Top 10:
Mamut americanum 11 tons. Deinotherium giganteum 12 tons. Palaeoloxodon recki 12,3 tons. Mammuthus columbi 12,5 tons. Stegodon zdanskyi 12,7 tons. Deinotherium thraceiensis 13,2 tons. Mammuthus trogontherii 14,3 tons. Palaeloxodon antiquus 15 tons. Mamut borsoni 16 tons. Palaeoloxodon namadicus 22 tons. Larramendi, A. (2016). Shoulder Height, Body Mass, and Shape of Proboscideans. Acta Palaeontologica Polonica 61(3), 537-574. |
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