Irish elk

The Irish elk (Megaloceros giganteus) was an extinct giant deer that lived across Eurasia during the Pleistocene and early Holocene. Males carried exceptionally broad antlers.

Megaloceros: An extinct genus of large deer that lived in Eurasia during the Pleistocene and early Holocene. The Irish elk is the best-known species in this genus.
Antler growth: The seasonal process by which deer grow antlers from living bone and later shed them. Annual growth produced the Irish elk's large antlers, which were shed and regrown.
Pleistocene megafauna: Large-bodied animals that lived during the Pleistocene, many of which later became extinct. The Irish elk was among Eurasia's conspicuous large Pleistocene mammals.
Ballybetagh Bog: A peatland site in County Dublin, Ireland, known for discoveries of Irish elk remains. Its fossils made the species especially familiar in Ireland.
Cervidae: The mammal family comprising deer, including living species and numerous extinct lineages. Its antlers and other traits place the Irish elk among deer.
Allometry: The study of how body parts scale in size relative to the body or to one another. Antler dimensions scaled unusually with the Irish elk's large body size.
Last Glacial Maximum: The interval of greatest global ice-sheet extent during the last glacial period, about 26,000 to 19,000 years ago. Its changing climates altered the environments occupied by Irish elk populations.
Isle of Man: An island in the Irish Sea between Great Britain and Ireland. Irish elk remains there illustrate the species' presence beyond mainland Ireland.
Deer antler: A bony structure grown and shed annually by most male deer and by female reindeer. The Irish elk's defining feature was its unusually large pair of antlers.
Sexual selection: Evolution driven by differences in mating success, including competition and mate choice. It is one proposed evolutionary explanation for the enlargement of male antlers.

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