Woolly mammoth (Mammuthus primigenius)
The last mammoth roamed through a Siberia-like Britain at the end of the last ice age. Woolly mammoths were about the size of a modern African elephant, growing to more than 9.8ft (3m) tall and weighing around 6 tonnes.
The thick fur that covered their bodies helped them survive the ferocious cold and wind of glacial Britain. The mammoth's coat was made up of an outer layer of long wiry hairs around 12in (30cm) long, with a shorter, thick, woolly layer underneath.
The exact reason for the mammoths' decline is unclear, but there are several possibilities. For one, humans were becoming sophisticated hunters. Intelligent groups working systematically to find and kill meant the woolly mammoth – one of the most enormous walking meals our ancestors had ever seen – didn't stand much of a chance.
Sudden swings in temperature toward the end of the last Ice Age made life hard for these enormous beasts too. On top of the natural changes in climate, mammoths were probably losing more of their habitat due to other human activities, as our ancestors began to cut down forests and establish small settlements.
After more than 100,000 years of surviving encroaching and retreating ice, huge swings in temperatures, and rising and falling seas, the mammoth finally died out from the British Isles around 11,000 years ago.
Woolly rhinoceros (Coelodonta antiquitatis)
The rhinos of ice age Britain, like the mammoths, were covered in thick fur to help them survive the vicious cold.
Like today's rhinos, this ancient species was massive and muscled, but these powerful creatures were herbivores. They had a similar low-set head on a thick neck with a long curved horn which they used for charging and fighting off predators rather than chasing prey.
Woolly rhinos arrived in Britain later than the woolly mammoths, and their populations dwindled there earlier too. In La Cotte, a ravine on the island of Jersey in the Channel between England and France, archaeologists found heaps of woolly rhino remains in a series of digs throughout the twentieth century. The remains suggest our ancestors had either been hunting or scavenging for rhino flesh.
"There were heaps of shoulder blades, all piled up," says Adrian Lister of the Natural History Museum in London, UK. "Some of them had knife marks on, as if humans or Neanderthals had been scraping the meat off them."
Although most of these remains are found on the island of Jersey, this was once part of a land bridge between Britain and continental Europe. When the ice age was at its coldest, sea levels were more than 330ft (100m) lower than today, exposing what's now the seabed.
This area between France and Britain has been called Doggerland. It was the route that rhinos and other giants of the ice age would have taken to and from the warmer climates of southern Europe.
Straight-tusked elephant (Palaeoloxodon antiquus)
This 13ft (4m) tall, 13-tonne elephant was significantly bigger than the woolly mammoth, if not so robust in the cold. Its long tusks looked like spikes.
Over the last half-million years they wandered in and out of Britain through Doggerland, heading to warmer climates when temperatures plummeted and returning to the north during warmer phases.
Like many of the giants of the ice ages, the straight-tusked elephant population had huge ranges. At its peak, its habitat spanned from central Asia in the east to Britain in the west. They could migrate massive distances when a shifting climate made it necessary, giving them a better chance of survival.
Britain lost the straight-tusked elephant for good around 120,000 years ago, towards the end of a particularly cold period. However they lingered on in warmer parts of Europe for tens of thousands of years, eventually being driven to the Iberian peninsula when humans became established in Europe.
Narrow-nosed rhino (Stephanorhinus hemitoechus)
This relatively unknown 6,600lb (3,000kg) herbivore grazed its way through Britain around the same time as the straight-tusked elephant. These beasts were around the same size as the endangered white rhino, with a shoulder height of 5-7ft (1.5–2m) and a body 10-13ft (3–4m) long.
The narrow-nosed rhino's habitat stretched as far to the east as China, but the species seems to have been commonest in Britain.
On the Gower Peninsula in south Wales, a series of caves punctuate the old sea line, which was a lot higher during the warm periods when narrow-nosed rhinos lived in Britain. Fossilised remains of narrow-nosed rhinos, as well as straight-tusked elephants, accumulated in these caves for thousands of years.
Narrow-nosed rhinos foraged in forested areas as well as open grassland. They were most comfortable in the warm spells when the ice retreated, although it took a protracted and bitter stretch of cold to push them out of Britain entirely.
It's been suggested that humans helped push them to extinction, but there isn't enough evidence to settle the question. Dramatic fluctuations in climate, and the changing landscape that followed, are likely to have played a role.
The narrow-nosed rhino had a very slow reproductive cycle, as did many of the ice age giants. This meant young only came along very infrequently, so populations would have struggled to replace themselves under pressure from hunting humans and Neanderthals.
Irish elk (Megaloceros giganteus)
Spanning 11.5ft (3.5m) from tip to tip, the ancient giant deer of the ice age had the largest antlers of any creature alive or dead. Each was as long as a person and weighed about 44lb (20kg).
The deer itself was more than a match to heft these weapons. Irish elk could have a body mass of 1320-1540lb (600-700kg), about the size of an Alaskan moose.
The archaeologists that first found the giant antlers were amazed and puzzled.
"People thought, how did these creatures move around with such enormous antlers? Wouldn't they be constantly bashing into trees?" says Jens-Christian Svenning of Aarhus University in Denmark. "But in these cold periods there were glaciers and tundra, and it was pretty open. That's why these creatures could do so well."
That is, until Neanderthals and humans came on the scene. Our ancestors soon developed tactics to hunt and overcome the elk, each of which was an enticingly large source of food.
Their antlers then became the Irish elk's downfall. Hunting groups could chase the deer into forested areas where its antlers would slow it down or injure it, or simply trap the animal before killing it with spears.
Scimitar-toothed cat (Homotherium latidens)
Deadly upper canines dropped down to the bottom of its lower jaw, with an incredibly sharp serrated edge for tearing through its prey. Its long front legs and sloping back give it a posture primed to leap. This bulky predator could reach up to 5.5 ft (1.7m) long and weighed in the region of 220lb (100kg).
The scimitar-toothed cat is a type of sabre-toothed cat, which are sometimes called sabre-toothed tigers. Actually these prehistoric felines didn't have much in common with tigers. They are more closely related to today's lions, with comparable size, bulk, and musculature.
They arrived in Britain nearly 0.75 million years ago, when the climate was relatively warm. It's less certain when they left. They may have gone extinct in the British Isles just a few tens of thousands of years ago. In 2000, fishermen dredged up a jawbone from the North Sea, which seems to be from about 28,000 years ago.
It's likely that the cats survived for thousands of years longer by moving south to warmer and more hospitable parts of Europe.
Cave bear (Ursus spelaeus)
The bears that lived in Britain through the ice ages were bigger than the largest bears alive today, the grizzlies. At 5ft (1.5m) tall at the shoulder and nearly 10ft (3m) long, they were formidable giants, weighing in at 880lb (400kg).
Their teeth and short, strong claws allowed them to take on some of the most fearsome predators of their era. The enormous bears were mostly herbivorous, but could eat meat if it was available. They wouldn't often have eaten humans, but we did our best to eat the bears.
"They were quite actively hunted by humans and Neanderthals," says Svenning. We also competed with the bears for space. "The caves were occupied by one species and then the other would come to drive it away."
The idea of driving an angry bear seven times your size out of a cave might seem ludicrously dangerous. But in the depths of an ice age it may well have been better to risk the bears than to stay out in the open.
Cave lion (Panthera leo spelaea)
Living at the same time as the bears, the cave lion was a far more dangerous animal. These were the largest carnivores of ice age Britain, standing 4.5ft (1.4m) tall at the shoulder. At their largest they could weigh as much as a cave bear.
"We would have avoided them like the plague," says Lister. "You don't hunt a cave lion."
Preserved cave art shows that our ancestors knew these beasts well.
Their paintings show that the males of the species didn't have the familiar majestic mane of their modern African relatives. Instead, a thick dense coat covered them to protect against the cold.
This subspecies of lion was 25% larger than modern African lions. This size and strength meant that, if lack of food pushed them to it, they could hunt the largest and most deadly prey. When the starving predator found an occupied cave it would fight anything within, including humans or even a gigantic cave bear.
Cave hyena (Crocuta crocuta spelaea)
Like the other cave dwellers of the ice age, this ancient breed of hyena was an exaggeratedly large version of its modern counterpart.
Cave hyenas could weigh up to 285lb (130kg). Their surviving relatives, the famous laughing hyenas of the African savannah, are usually closer to the 130-150lb (60-70kg) range.
The cave hyena had an awkward raised posture because of its long front legs. Its low-hanging head gave it the loping gait and boar-like posture of the modern hyena.
Their massive molars could crush bone and helped them hang onto and incapacitate the largest of prey. They're known to have even hunted woolly mammoths, although they were also voracious scavengers.
Cave hyenas lived and hunted in social groups, with a pack numbering up to 30 individuals. Archaeologists have found more than 20,000 cave hyena teeth at Tornewton Cave in Devon, showing that clans inhabited these caves for many generations.
In the bitter cold, access to cave space could mean life or death for an animal. "Humans and hyenas were competing for cave space," says Lister. "We find layers of hyena remains and then a layer of human remains."
Aurochs (Bos primigenius)
These creatures were the ancestors of modern cattle. They were domesticated once in Europe and once in south Asia. Taming an aurochs would have been an incredibly difficult and possibly deadly task, which is why it only happened twice.
They were huge bull-like creatures that came to Britain over the land bridge from Europe about 400,000 years ago.
Aurochs had thick, curving horns, which their skulls were specially adapted to support. They were about 5.2-6ft (1.6-1.8m) tall at the shoulder, but their size fluctuated over the years, varying from 3,300lb (1,500kg) to an enormous 6,600lb (3,000kg) at its peak.
To maintain their bulk, aurochs sought out open, low-lying grazing land as the richest source of food for a herbivore.
Aurochs were one of the few giant animals to persist in Britain after the end of the last icy period about 11,000 years ago. "They survived very well in other parts of Europe even up to the 1600s," says Svenning.
But as our ancestors started to build settlements, cultivate crops and breed animals, the aurochs were slowly pushed out. "Eventually the aurochs became globally extinct after a long, long history of human persecution," says Svenning. Only their domesticated descendants survived.
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