Introduction:PleistoceneMegafauna is the umbrella term used for large and giant mammals that were aliveduring the Pleistocene epoch and who became extinct at end of the Quaternary periode through many different events. Megafauna included animals such as the Mammuthus primigenius JL3 (WoollyMammoth), Coelodonta antiquitatis(Woolly Rhinoceros) and the Megalocerosgiganteus (Giant Deer).
The Pleistocene epoch is the first epoch of theQuaternary period, which lasted for about 1 600 000 years and it was characterizedby extensive glaciations in the Northern hemisphere and witnessed theevolutionary development of man, (Collinsdictionary.com, 2017JL4 ) In the past megafaunal extinctions in the latePleistocene epoch have been explained by ‘overkill’ by human hunters, as wellas climatic/ vegetational changes following the end of the last ice age(Devensian). However, in the last decade the assumptions that the megafauna ofNorth-eastern Eurasia had disappeared at the end of the Pleistocene epoch havehad to be re-evaluated by the discoveries of the remains of much younger woollymammoths on Wrangel Island off the north Siberian coast. This essay willillustrate the nature of late Quaternary megafauna and demonstrate how reconstructingtheir biogeography and extinctions can be related geographical studyJL5 . Mammoths: Old WorldJL6 The Mammuthus primigenius JL7 was anenormous mammal that was believed to have remained in the wild until roughly1700 BC when it was considered to be extinct. Mammuthusprimigenius JL8 weretypically found Arctic tundra, they were often in herds in order for warmth duringthe cold season and for protection against predators. Due to the sheer size ofthe Mammuthus primigenius JL9 thelarger mammals had only a few significant predators.
The Sabre-tooth cats wouldoften target the Mammuthus primigenius JL10 calves because they were easier target. The Mammuthus primigenius’ appearance was similar to that of its closet living relativethe Elephas maximus (Asian Elephant). The mammal reached approximately 3.5 metresat shoulder length and on average weighed approximately 6-8 tons. The Mammuthus primigenius JL11 had alarge range, apart from the continents of Australia, South America and Antarctica,Mammoth fossils have been fund on every continent (National Geographic, 2011). Mammuthusprimigenius were based on a herbivore diet.
Researchers believe that the Mammuthus primigenius JL12 consumed on average 225 kilograms of plants, grasses,aquatic shrubs and trees daily (National Geographic, 2011) In order to consumethis vast amount of vegetation the Mammuthusprimigenius JL13 had “four giant, shoe box-sized teeth- two upper and two lowers”(National Geographic, 2011) Over their lifetime the mammal grew six sets ofteeth. Their life depended on their teeth and usually died when their last setof teeth lost ability to grind up vegetation, this was normally from the agesof 60-80 years. TheMammuthus primigenius JL14 is stillof great scientific research, with many specimens being preserved andinspected. In August 2010, a mummified carcass of the 39,000-year-old woollymammoth with a well-preserved cerebellum was found off the Laptev Sea coastnear Yukagir, Russia.
The Mammuthus primigenius JL15 , that researchers named Yuka, was 6 to 9 years old when itdied. Anastasia Kharlamova, of the Research Institute of Human Morphology,Russian Academy of the Medical Sciences was the key researcher on the project.Scientists and Geographers have a strong interest in megafauna of this period, becausethe research can provide more information on the spatial patterns of themammals at the time providing indications of changing environments and climatechange. Mammoths:New World Duringthe Pleistocene epoch, several types of mammoths walked the planet. As well asthe Mammuthus primigenius, the Mammuthus columbi wasalso present. However, they were only found in the North American regions. The Mammuthus columbi was believed to havefirst made an appearance in North America about one million years ago. It hasbeen suggested that it was evolved from an earlier species of Mammuthus that had previously crossedinto Northern America in the early Pleistocene epoch.
There are many differencebetween the Mammuthus primigenius, and the Mammuthuscolumbi. The Mammuthus columbistood at an average of 4m in shoulder height, 5m taller than the average Mammuthus primigenius. Other than sizethe most significant difference between the two mammoths was their hair, due tothe different spatial positioning of the Mammuthus’they had evolved differently, Eurasia was considerably colder than the warmerregions of Northern America, therefore the Mummuthus columbi did not need a thick woolly coat. MammothExtinction Untilrecently it was thought that Mummuthus (old& new World) died out at the end of the last ice age due to climate change,changing habitats and the shrinking areas of the Mammoth Steppe.
The MammothSteppe was one of the largest biomes on the Earth, it spanned from the East ofSpain across Eurasia to Canada. It is surrounded the Arctic Islands and carriedon southwards to Chine (Guthrie, R.D. 1990).
Manymegafauna including the Woolly Mammoth, Giant Deer and Woolly Rhino flourishedalong the “tundra-steppe” landscapes which was a significant portion of theMammoth Steppe, in the Siberian Arctic due to the specific kind ofpalaeo-vegetation biome, during the transition from the late Pleistocene to theearly Holocene the disappearance of the tundra steppe occurred. Researchershave assumed that the cold dry climate switched to a warmer wetter climatethat, which resulted in the disappearance of the grasslands and the megafauna thatwere dependant on them (Guthrie, R.D.
1990). As well as this change, a significant part ofWrangel Island was subject to thermokarst, thermokarst is a form of periglacialtopography resembling karst, with hollows produced by the selective melting ofpermafrost. (Oxford Dictionaries, English, 2017). This resulted in the northward expansion ofsubarctic vegetation across North-Eastern Siberia, this led to the northernmigration of mammoths. The specific paleo-vegetation was replaced with theemergence of the modern Arctic Tundra vegetation.
The disappearance of thetundra-steppe is considered to be the main reason for the extinction of manylarge late Pleistocene herbivores.Anexception to this is the fact that mammoths survived throughout a large proportionof the Holocene on Wrangel Island, there are many similarities between theconditions of Wrangel Island and those of the Siberian Arctic of today,therefore they were able to survive under those conditions. The discovery ofthe Wrangel Island Mummuthus contradictsthe previous theory that the extinction of these megafauna occurred in arelatively short space of time The special patterns of Mega Fauna in North-EastSiberia have been of great interest of researchers and geographers, due tochanging vegetation in the seasons, for these reasons during in the warmperiods there was a large number of mammoth’s present, however these numbersreduced in the colder months as mammoths retreated further south, to haveaccess to the subarctic region.
JL1Betteras one word – ensure consistency throughout AMCB2 JL3Ensureall Latin names are always in Italics JL4Geographicaldictorionaries / text books better e.g. Lowe & Walker 1997. Reconstructing Quaternary Environments –available in the library.
JL5Themakings of an excellent introduction! JL6Thissection could explain in more detail the nature of woolly mammoths (Mammuthusprimigenius). What they looked like,where they lived in Europe / Asia (Mammoth steppe habitat – other animalspresent?). Details of how they have beenpreserved / where why? Who hasinvestigated these mammoth finds or used mammoth bones? JL7Ensureall Latin names are always in Italics JL8Ensureall Latin names are always in Italics JL9Ensureall Latin names are always in Italics JL10Ensureall Latin names are always in Italics JL11Ensureall Latin names are always in Italics JL12Ensureall Latin names are always in Italics JL13Ensureall Latin names are always in Italics JL14Ensureall Latin names are always in Italics JL15Ensureall Latin names are always in Italics