Big Prehistoric Mammalian Herbivores ~

[brotherbear]

http://www.mothlightmedia.com/when-eleph...fhfZOvkaL0    
     
When elephant sized camels roamed north America. 
  
The dromedary or Arabian camel is a well adapted creature for life in arid and extreme climates like the Middle East and the Sahara desert. Medieval Arabs use to breed these camels alongside horses to use both of their strengths even being known to use the camels to carry water for the horses as they could last so much longer without a drink. The features that allow not just this domesticated version but all camels to thrive in these extreme environments are their fleshy humps containing fat reserves, and their spread out feet making sure they don’t sink into the sand. Camels are also able to rehydrate faster than any other mammal gulping down 110 litres of water in 13 minutes and they even sweat more efficiently letting out as much heat and as little water as possible. The dromedary was domesticated 4000 years ago in either Somalia or the Arabian Peninsula.

The camelid family is unusual as their current distribution is almost the inverse of their place of origin, you see, camels evolved in North America but have now gone extinct. Adding to this despite their current suitability to arid environments the 45 million year old climate they first evolved in was much hotter than today making it a jungle like environment. The earliest considered camelid was almost the size of a hare, extraordinarily diminutive considering how large some camels are today. The small stature of Protylopus was not the only thing that it didn’t have in common with modern camels as it morphologically resembled a gazelle. In fact the only thing that ties it to modern camels are its unusual camelid teeth as camels possess dentures fairly unique among mammals. 5-10 million years later poebrotherium came onto the scene which had evolved away from four toes to the famous two toes we see on camels today. This camel was very successful which led to a large diversification of camel species in the Oligocene. This large diversification included the sub family that would give rise to modern day camels along with some notability strange camels by today’s standards. Aepycamelus had a very long neck and long legs resembling a giraffe, the north American climate that this camel evolved in was similar to the African savannah showing that this resemblance was probably convergent evolution. Keeping in with the theme of the African savannah another camelid, although didn’t look anything like an elephant, was the size of one, standing 3.5 meters at the shoulder. Titanotylopus lived during the Miocene and possessed a large hump on its back evidenced by the elongation of its vertebrae. The Miocene seemed to be a good time to be a camel as they are one of the most common animals found in North American Miocene fossil beds. 

   It wasn’t until as little as 6 million years ago that camels finally started to cross the Bering land bridge into Asia. The species to do so was called paracamelus that’s earliest fossils were found in Nevada 10 million years ago and had arrived in Spain and Italy in as little as 4 million years later. Around this time another species of paracamelus called the high arctic camel lived in Alaska and on the north of Bering land bridge. Just before the ice age the earth was going through a slight warm period so it might have been as cold as today but was probably still cold enough to snow. The scene of a camel living out its life in the snow within the Arctic Circle certainly juxtaposes the common associations with camels. However, their adaptations that help them thrive in the desert may be what helped them survive in the extreme climate of Alaska. Being able to store energy in their hump may have sustained them when there was less plant life in the winter and their feet may have stopped them from sinking in the snow. 
    
Unfortunately camels have now all gone extinct in North America but when camelids were crossing the bering land bridge they were also crossing another land bridge that had opened up into south America. Camelids crossed over to South America where they still live today, lamas and alpacas are camelids that are distantly related to modern day camels.

http://www.theinfolist.com/php/SummaryGet.php?FindGo=camel
Harington, C. R. (June 1997). “Ice Age Yukon and Alaskan Camels”
https://www.thestar.com/news/world/2013/03/05/camel_fossils_discovered_in_canadas_arctic_shed_light_on_animals_evolution.html
Björn Kurtén and Elaine Anderson: ‘Pleistocene Mammals of North America’ Reply