Megaloceros, also called the Irish  Elk, has possibly the most fitting  name of any prehistoric animal.  Meaning "Great Horn," Megaloceros  had enormous antlers that spanned  3.65 meters. Only males had these  massive antlers, and they shed and  regrew them every mating season. They  were probably used to impress the  ladies, because who could resist such  handsome headgear? In addition to its noteworthy antlers, this stunning lad was a massive two meters tall at the shoulder! Megaloceros is also  one of few animals that are depicted in prehistoric cave paintings, so we can actually see how it looked in  life. The art shows Megaloceros with a large, boldly colored hump on its  shoulders and dark stripes sweeping down its elegant body.  This horny deer lived in Europe and Asia during the Pleistocene in open forest and meadow habitats. It was hunted by cave lions, cave hyenas, and cave wolves (oh my!). Evidently,  since cave paintings of Megaloceros  exist, it also regularly encountered  early humans. There are many  theories about why the Megaloceros  went extinct, including overhunting  by humans; other theories argue that  their foods lost quality over time, meaning that they could not get  sufficient nutrients to live.  Surprisingly, their closest modern relatives are not elk or moose, as  could be expected, but are actually  fallow deer.