Gould demonstrated that for deer in general, species with a larger body size have antlers that are more than proportionately larger, a consequence of allometry, or differential growth rate of body size and antler size during development. Irish Elk had antlers of the appropriate size in correlation to their massive bodies. This does not mean that sexual selection played no part in maintaining large antler size, only that the antlers of the species' ancestors were already large to begin with. Indeed, Gould concluded that the large antler size and their position on the skull was very much maintained by sexual selection: they were morphologically ill-suited for combat between males, but their position was ideal to present them to intimidate rivals or impress females. Unlike other deer, M. giganteus did not even have to turn its head to present the antlers to best effect, but could accomplish this by simply looking straight ahead.[12] In 1987, Kitchener presented evidence that Irish Elk antlers were in fact used for fighting.[13] In addition, the Irish elk's antlers had several functions such as being a display for attraction of females and dominance of rival males.[14] The elks shed their antlers and re-grew a new pair during mating season.[15] Not much is known about the Irish elk's mating system, but according to Cedric O'Driscall Worman, often the norm was low male/female ratio and of these males, few bred successfully. The number of offspring produced by a female Irish elk was only 1 per mating season. Ultimately, the decrease in energy intake by the Late Pleistocene, influenced the ability to produce for Irish elk females.
Gould demonstrated that for deer in general, species with a larger body size have antlers that are more than proportionately larger, a consequence of allometry, or differential growth rate of body size and antler size during development. Irish Elk had antlers of the appropriate size in correlation to their massive bodies. This does not mean that sexual selection played no part in maintaining large antler size, only that the antlers of the species' ancestors were already large to begin with. Indeed, Gould concluded that the large antler size and their position on the skull was very much maintained by sexual selection: they were morphologically ill-suited for combat between males, but their position was ideal to present them to intimidate rivals or impress females. Unlike other deer, M. giganteus did not even have to turn its head to present the antlers to best effect, but could accomplish this by simply looking straight ahead.[12] In 1987, Kitchener presented evidence that Irish Elk antlers were in fact used for fighting.[13] In addition, the Irish elk's antlers had several functions such as being a display for attraction of females and dominance of rival males.[14] The elks shed their antlers and re-grew a new pair during mating season.[15] Not much is known about the Irish elk's mating system, but according to Cedric O'Driscall Worman, often the norm was low male/female ratio and of these males, few bred successfully. The number of offspring produced by a female Irish elk was only 1 per mating season. Ultimately, the decrease in energy intake by the Late Pleistocene, influenced the ability to produce for Irish elk females.
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