Robert Clarkのインスタグラム(robertclarkphoto) - 2月7日 12時39分

The size of #IrishElk antlers are distinctive. Scientists have proposed multiple theories regarding the #evolution of these antlers. One theory is that their antlers, under constant and strong #sexualselection, increased in size because males were using them in combat for access to females. Thus, it is hypothesized that they eventually became so unwieldy that the Irish Elk could not carry on the normal business of life and so became #extinct. It was not until Stephen Jay Gould's important 1974 essay on #Megaloceros that this theory was tested rigorously.

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. his 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 rivals to impress the ladies.
Irish Elk stood about 2.1 metres (6.9 ft) tall at the shoulders carrying the largest antlers of any known cervid (a maximum of 3.65 m (12.0 ft) from tip to tip and weighing up to 40 kg (88 lb). @thephotosociety @ナショナルジオグラフィック @instituteartist @Robert Clark

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