Irish Elk Profile
Not long ago, a fisherman in Northern Ireland pulled his nets up to find an enormous set of antlers. Holding them together was a long and narrow cranium, one that once protected the brain of the largest deer species to have ever lived.
Appropriately named the Irish Elk, this prehistoric giant spanned much of Northern Europe until their extinction around 7000 years ago.
Irish Elk Facts Overview
| Habitat: | Meadows and open woodlands |
| Location: | All across Northern Eurasia |
| Lifespan: | Unknown |
| Size: | 2.1 m (6’ 11” in) tall |
| Weight: | Up to 700 kg (1,540 lb), |
| Colour: | Light colour, with a dark stripe |
| Diet: | Grass |
| Predators: | Cave hyenas, humans, cave lions |
| Top Speed: | Fast |
| No. of Species: | 1 |
| Conservation Status: | Extinct |
Irish elk are so-named because the peat bogs of Ireland turn up so many of their remains. But in reality, they spanned the entire breadth of Eurasia along with at least seven other species of giant deer.
These in particular were the largest, and likely the heaviest deer species there ever was. Their antlers were formidable, and a testament to their strength and fitness.
These long-distance athletes thrived in the high calcium grasses of the Steppe and likely died out as a result of climate change taking away their roughage.
Interesting Irish Elk Facts
1. It was probably a fallow deer
The genus Megaloceros included at least eight species of huge deer, spanning most of Eurasia, from the Iberian Peninsula to China. M.giganteus, as the name suggests was the largest, but there’s still a lot of debate as to what the genus is most closely related to.
Until fairly recently, it was thought to be a branch of the red deer lineage, Cervus, but more recently it’s thought that the Irish elk – far from being either – was a relative of the fallow deer.
However, there are debates ongoing about which of these lineages is the true one, and some evidence suggests that M. giganteus interbred with Cervus species in Europe. As of now, there’s still a lot to uncover about where these huge deer came from. 1
2. They had the largest antlers ever
These are antlers that inspired awe in humans across the ages. At almost four meters long and weighing up to 40kg, they have been present in ancient cave paintings and medieval castle halls.
They’ve also inspired debate in the scientific community; bringing up discussions on sexual selection, extinction, evolution, and physiological proportions in the animal kingdom.
This deer was the size of an Alaskan moose, and even heavier. It’s the heaviest known member of the Cervinae family, with a much thicker and stronger skeleton than even its extinct, larger relatives. 2
3. They had the hump
The skeletons of these deer all display a large protrusion of bones on the back of the cervical spine. These protrusions would have supported a huge hump on the neck of the animal.
Humps have numerous useful applications. They can be fat storage like in camels, or act like a biceps on the back of the neck, pulling enormous heads through thick snow or mud. They can help keep an animal warm or reduce overheating by localising reserves to reduce insulation during a long run.
And this last point is likely the most applicable here since the Irish elk was likely the most cursorial of any deer species known. 3
4. They were built to run
Not only were they strong, they were likely powerful endurance athletes, too. The huge ribcage housed a proportionally large heart and lungs, perfect for an open-plains runner.
The spines on the back of the neck would have anchored ligaments and muscles to counter the tremendous downforce of the antlers on the male’s neck. Incidentally, these structures of the neck are also found in fallow deer, something which some say is evidence of a distant relationship.
They would have also been able to provide storage space for the extra fat needed to survive the rut; a period of aggression and starvation in male deer during which they defend harems and fight with competitors for mating rights.
5. They ate grass
Judging from wear patterns on the molars of the deer, it seems as though grass was the predominant source of food.
The silica in grassy plants is what gives them rigidity and coarseness, and this creates a distinctive wear pattern as the teeth are effectively sanded down over time. Irish elk and cow teeth both show these wear patterns, implying a similar diet.
And a long-distance runner with enormous antlers would have needed to eat a lot of grass.
6. Some think the antlers held them back
The antler-extinction hypothesis predicts that as the vast ice age plains, thick with calcium-rich grasses, gave way to more sandy, low-productivity soils, an animal with such high nutritional requirements would have no longer been able to maintain its physique.
While climate change is very likely to have caused the rapid decline of Irish elk in this period, there are contenders to this hypothesis that suggest the antlers had nothing to do with it.
7. Female reproductive capacity may have had more impact
Sexual selection is a powerful force. It’s significantly less random than plain old natural selection, and therefore it happens a lot faster.
One of the arguments against the heavy-headed hypothesis is that there would have been enough time for males with smaller antlers to have been selected for. Further, deer with poor diets typically produce smaller antlers, so even on a seasonal basis, if food was scarce, antlers would have likely been smaller.
One team of researchers suggests that it wasn’t the males at fault; the females’ reproductive output would have dropped to around half as a result of the decline in nutrition, likely contributing far more to the extinction of the species than the encumberment of the male’s antlers. 4
8. Humans would have helped
A reduction in body size preceding the extinction would have likely been from nutrient restriction, especially in areas where Irish elk lived without humans.
But there’s no question that hunting would have provided another extinction pressure on the deer populations in areas of human presence too. 5
Irish Elk Fact-File Summary
Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Family: | Cervidae |
| Genus: | Megaloceros |
| Species: | Giganteus |
Fact Sources & References
- Beth Askham, “The Irish elk: when and why did this giant deer go extinct and what did it look like?”, Natural History Museum.
- “The Case of the Irish Elk”, UCMP.
- Real Wild (2023), “Giant Irish Elk: The Largest Deer To Ever Live”, YouTube.
- Cedric O’Driscoll Worman (2008), “Getting to the Hart of the Matter: Did Antlers Truly Cause the Extinction of the Irish Elk?”, JSTOR.
- Cedric O’Driscoll Worman (2008), “Getting to the hart of the matter: did antlers truly cause the extinction of the Irish elk?”, Wiley Online Library.