I was in Los Angeles when I first saw him. I stood in his shadow as he towered above me. I didn’t feel fear. Or panic. I felt awe despite being dwarfed. Light bounces off each bone, highlighting the curves, the detail, the sheer size. A gigantic skeleton; the internal frame holding up a body of immense proportions. I recognised each bone as I would old friends: a femur at the top of a back leg, vertebrae running along the back of the animal, ribs protecting what would have been the delicate organs beneath. Yet despite him and I being practically the same bone for bone, his were enormous, thicker, stockier, stronger. What’s more, he had two enormous tusks protruding from his face, which curve dramatically outwards and in on themselves. This magnificent beast was the Columbian Mammoth. A goliath from the past.
How did this giant find itself in Los Angeles when elephants alive today are found in Africa and Asia? Was it related to the Woolly Mammoth? Was it hairy? Did humans see these animals? What is a mammoth?
One enormous skeleton. A mountain of questions.
To find the answers we will have to travel back in time and space. Back to Africa. Back to the very beginning of this iconic group of animals.
Yours truly standing under a composite skeleton of a magnificent Columbian Mammoth. The specimen is on display at the Page Museum, La Brea. This incredible museum and active excavation site is sat right in the middle of busy LA. (Photo by random museum visitor)
Mammoths belong to the Order Proboscidea, which has its roots back in the African Paleocene around 60 million years ago. (We, for example, are classified in the Order of Primates. We share this Order with the other primates: gorillas, chimpanzees, monkeys, gibbons, lemurs and lorises) The Proboscidea was pretty spectacular and included many weird species, such as the odd pig-hippo creature, Moeritherium and one of the largest mammals to have walked the Earth, Zygolophodon.
This Order was once astonishingly diverse with 13 different Families holding dozens of different species that migrated into Europe, Asia and the Americas. Just three species of this once successful group survive today; the African Savannah Elephant (Loxodonta africana), the African Forest Elephant (Loxodonta cyclotis) and the Asian Elephant (Elephas maximus), all belonging to the last surviving Family of the glorious Proboscidea; the Elephantidae.
The variety of proboscideans (Artworks by Vladimir Nikolov.
Editing and digital work by Docho Dochev.) (Image from here)
Originating in Africa just around 5 million years ago the Elephantidae has included a huge number of species, from the ‘first elephant’, Primelephas, to the giant extinct straight tusked elephant, Palaeoloxodon. It is special because it is the last surviving Family of a once great and diverse group. It is also special because it includes the mammoths!
The word ‘mammoth’ has slipped into our everyday language as an adjective meaning enormous, massive or huge. (I do quite like it when I hear a friend or colleague describing something as mammoth without realising it.) It has also become synonymous to describe any large hairy ‘elephant’. Forgive me for a moment while I get a little bit passionate about what is and what is not a mammoth.
Mammoths are any species belonging to Mammuthus. Not other large Probosidea or other elephant relatives. Mastodons were not mammoths: they lived on a separate branch to mammoths for around 28 million years. (Mastodons belong to the genus Mammut, confusing, but still not a mammoth.) The freaky Gomphotheres were not mammoths. Nor were the huge Straight Tusked Elephants. Only mammoths were mammoths. These other large beasts may superficially look like mammoths, but they are not. They are, however, wonderful examples of divergence, where similar features are from a shared ancestor (for example, tusks, large flat teeth, massive bodies) evolve to look a little similar later on in different species.
The First Mammoth
Now you know what a mammoth is not. What then makes a mammoth: how do we know what species belong to Mammuthus? One diagnostic features of a mammoth is the inward curving tusks, which you saw in the magnificent Columbian Mammoth we met earlier. The skulls of mammoths were flatter and higher than their relatives, which went arm in arm with more highly crowned teeth for a change in diet. We see the beginning of these features back in the Pliocene around 5 million years ago. Indian elephants and mammoths shared a common ancestor and lolloped their separate ways sometime about 5 million years ago. One of these populations evolved into first true mammoth (Mammuthus subplanifrons). Fossils have been recovered in Eastern and Southern Africa, with associated fossils suggesting a warm, tropical environment. From this warm loving (hairless) giant stomped a whole parade of different species!
The Frist Mammoth (Mammuthus subplanifrons), evolved in Africa around 5 million years ago. (Image by Twilight Beasts)
The African Mammoth
M. subplanifrons, the First Mammoth, disappears around 3 million years ago, around the same time the African Mammoth (M. africanavus) appears. One small population of the First Mammoth evolved into the African Mammoth, while shortly after the rest of the first founding species vanished. Relatively smaller than more recent mammoths, the African Mammoth was distributed across Western Africa. This rather inconspicuous species was around for a long time, with the last evidence from rocks showing it lived until 1.65 million years ago. It disappeared from the African continent, but not without leaving a legacy: the Southern Mammoth.
Not a huge mammoth, but still a mammoth. The African Mammoth (Mammuthus africanavus). (Image by Twilight Beasts)
An enigmatic Mammoth
Before we meet the mighty Southern Mammoth, there is an enigmatic mammoth that was the first species to have left Africa (M. rumanus). Fossils have been found in Britain and in sites in Europe, but with only fossil teeth being discovered so far, it remains poorly known. Sadly, the further back in time we go, the fewer fossils we find (land animals do not often preserve as fossils: carcasses are eaten, bones dragged away from the body, bones trampled on). It may have its origins in Africa, around 3.5 million years ago, likely from the First Mammoth, M. subplanifrons. It did manage to make it out of Africa and into Europe, and it may well have left descendants in the form of the world’s smallest mammoth.
Still hairless, the Enigmatic Mammoth (Mammuthus rumanus) was the first mammoth species out of Africa. (Image by Twilight Beasts)
The Cretan Dwarf Mammoth
On the hot island of Crete, in the early 1900s, the young palaeontologist and explorer, Dorothea Bate discovered some fantastical creatures. An odd sheep that could have been a goat (or was that the other way round?), pygmy hippos, and dwarf mammoths. Yes. A huge oxymoron. But a real creature that once lived. A mammoth that was just 1 meter tall: the Cretan Dwarf Mammoth (M. creticus). How animals get relatively larger or smaller on an island is explained by the Island Rule (or Fosters Rule). Smaller animals on islands are more likely to survive on fewer resources than bigger ones, so natural selection will favour the smaller individuals, and each generation becomes smaller and smaller. Island dwarfism is a fairly common phenomenon and has been seen with dwarf elephants, hippos, deer, and even a species in our own genus, Homo floresiensis.
For a long time, this little animal was thought to have been a mini elephant, descended from the Straight Tusked Elephant. Recent reanalysis by Trowelblazer extraordinaire, Tori Herridge and colleague Adrian Lister, examined in great detail the teeth and showed that it was actually a mammoth! Evidence of its ancestors is sketchy, morphological similarities with the Enigmatic Mammoth, M. rumanus suggest it may push back to 3.5 million years ago. This was the smallest mammoth to have ever lived. For such a remarkable creature relatively little is actually known about it. The teeth indicate that it ate low bushes instead of grass or tree. With the warm Mediterranean climate, this mini-mammoth was not a hairy beast. It is not known for certain when it became extinct, but there is nothing to suggest that humans were responsible. Despite size, this remarkable little animal was a true mammoth. Small but mammoth!
The smallest mammoth that has ever lived, the mighty-mini Cretan Dwarf Mammoth (Image by Twilight Beasts)
So far that is four species of mammoth: the first mammoth M. subplanifrons, the African Mammoth M. africanavus, the enigmatic M. rumanus and the wonderful mini-mammoth, M. creticus. I wouldn’t be disappointed if that was the end of the line of mammoths. These early species were amazing! Mysterious, huge, tiny: successful animals that once lived and breathed.
Things get even more interesting. Evolution happens a lot faster (relatively speaking) when there are more extreme changes in the environment. Think of when the non-avian dinosaurs disappeared: mammals, birds (avian dinosaurs), and a whole range of other groups radiated into lots of new species in a relatively short time of just a few million years. Animals either cannot cope and die, or are lucky enough to have a random mutation that turns out to be useful. Pure luck can either be the saviour, or demise, of a species. The Pleistocene was full of big changes. This whole Epoch, from around 2.6 million years ago to 10,000 years ago was the Ice Age. It was full of extreme changes in the environment, from periods warm enough to allow hippopotamus to bathe in English Rivers, to periods cold enough for massive glaciers to cover all of Canada. The enormously erratic climate of the Pleistocene was one of the main factors in the evolution of the impressive and iconic Ice Age Beasts. This was no doubt the key driving force for the rapid evolution of the later mammoth species.
The spectacular species of mammoths. Not that there were some early evolutionary dead ends. At many times there were more than one species of mammoth lolloping on Earth. Click on the image to see more detail. (Image by Twilight Beasts)
The Southern Mammoth
And it begins sometime around 2.5 million years ago when one population of the African Mammoth evolved into a wandering giant, the Southern Mammoth (M. meridionalis). With earlier mammoths having a smaller number of ridges on their teeth, the Southern Mammoth had between 12 and 14 ridges on top of low crowns – teeth made for pulverising leaves and shrubs. (Think of a pestle and mortar – the massive teeth of mammoths ground down the vegetation into a slush.) Fossils found with Southern Mammoth remains indicate an environment much different from one you would imagine a mammoth to be at home in: deciduous woodlands. Some specimens at sites in much drier climates (such as Israel and Georgia) have been found with evidence of more grassy environments (similar to the African savannah today). Living in these warmer climates also suggests this giant was not a hairy giant, but likely had similar thick skin to elephants around today.
A flatter higher skull than it’s ancestors and more ridges on those thick molars, the mammoth Southern Mammoth (Mammuthus meridionalis) was a magnificent beast. (Image Twilight Beasts)
The Southern Mammoth was not only capable of adapting to different habitats due to those big, ridged molars, it also travelled very far. Remains have been found in Africa, Europe, Russia and China. This very successful species was on Earth for over a million years. With major changes in the Earth’s climate around 1.5 million years ago, many populations died out. Smaller numbers lumbered along, eventually disappearing over the horizon forever 600,000 years ago.
Before their extinction, one population became standard from other populations. Cold, alone, isolated, this group evolved into a mammoth that would cross an ocean.
The Steppe Mammoth
In the cold, dry grasslands of Siberia, a group of the mighty Southern Mammoth adapted to the cold environment. Around 700,000 years ago we see the first fossils of the enormous Steppe Mammoth (M. trogontherii) descended from this Siberian Southern Mammoth population. With more enamel ridges on those massive molars than its predecessor (up to 19 ridges), the Steppe Mammoth was well suited to eating tougher vegetation on the harsh tundra. Very likely to be the first truly hairy mammoth, this species spread across what was becoming a rich fertile ground for grasses and shrubs and a whole variety of different Pleistocene fauna. They moved West, back over Europe, and even into England, with the famous West Runton Mammoth found in 1990. They also moved east, across Siberia, across the Bering Strait, into Canada, and down into North America.
This was the mammoth that conquered the northern hemisphere.
The largest mammoth of them all, the mighty Steppe Mammoth (Mammuthus trogontherii). (Image by Twilight Beasts)
Sardinian Dwarf Mammoth
The Steppe Mammoth had a huge range across Europe. Some even made it (probably swam) to the Mediterranean island of Sardinia, with later generations becoming smaller and smaller. Around 450,000 years ago, what was once the largest of the mammoth species, quickly evolved into one of the smallest; the Sardinian Mammoth (M. lamarmorai). Isolated from other populations of Steppe Mammoths, the Island Rule forced this mammoth to shrink to a loveable size. It also allowed other wonderful creatures to evolve, including dwarf hippos and giant hares.
Some islands in the Mediterranean were home to dwarf elephants, descended from the large Straight Tusked Elephant, which may be why the Sardinian Mammoth stayed in Sardinia. (If the Sardinian Mammoth managed to make it to another island, there would have been well established populations of dwarf elephants, putting a lot of competition to this newcomer.) This little Sardinian Dwarf Mammoth disappears around 40,000 years ago. Human remains dated to around 13,000 years old have been found on this island, as well as flints that may date much earlier. The extinction of this wonderfully small mammoth may have been due to the arrivals of humans, although without more detailed work on this species, at the moment we don’t know why it vanished for sure.
If you were to call a mammoth cute, the Sardinian Dwarf Mammoth (Mammuthus lamarmorai) would be that mammoth. (Image by Twilight Beasts)
The Woolly Mammoth
Elsewhere in Europe, as the climate shifted once more, the Steppe Mammoth slowly disappeared. Fossil indicate that 400,000 years ago in Siberia it adapted to the changing, bitter landscape, evolving into the most familiar of all the mammoths, the iconic Woolly Mammoth (M. primigenius). These were true ice age beasts. Thick shaggy hair and layers of fat helped protect them from the icy temperatures. And it was cold. An enormous belt of tundra covered northern Europe all the way across to northern America. Called the Mammoth Steppe, this environment was cold but rich in grasses and shrubs to sustain not only Woolly Mammoths, but giant deer, reindeer, woolly rhinoceros and deadly predators like cave lions and sabre tooth cats.
The Woolly Mammoth was at home on this Steppe, a rich ecosystem on the edge of enormous glaciers. With water locked into the great glaciers during the glacial periods, sea levels were much lower, exposing land and connecting continents, and fossils have been found all over the northern hemisphere. Across Siberia the Woolly Mammoths moved down through Canada and into North America. Yep. The Woolly Mammoth was not just a European species.
At least two human species, Homo sapiens and H. neanderthalensis relied on the Woolly Mammoth for survival. Cut marks on bones, burnt bones, cave art, and even evidence of huts made from mammoth bones show that these hairy giants were key to the survival of these humans. All across the northern hemisphere, mammoth populations plummeted towards the end of the Pleistocene. Human hunting had an effect and sadly this coincided with a warming climate. The end of the Pleistocene saw the great glaciers melt, and the Steppe environment slowly retreat north. The Woolly Mammoth clung on to this shrinking environment for as long as they could. One small population managed to survive a little longer on a small island north of Siberia, Wrangel Island. Isolated from predators, this island was their Eden. Until humans arrived. And just 4000 years ago the last of the amazing line of mammoths vanished forever. 4000 years. There were mammoths alive when humans had started writing 5500 years ago. Mammoths were even around when the great pyramids of Egypt were built. They were an incredible group of animals. And they so very nearly made it to today.
The shaggiest mammoth of them all, the one most adored, the Woolly Mammoth (Mammuthus primigenius) (Image by Twilight Beasts)
The Columbian Mammoth
And what of our giant we met at the beginning of this post? Although Woolly Mammoths did make it across to North America, this giant was a different species: it was the enormous Colombian Mammoth (M. columbi). For a long time it was assumed that the enormous Columbian Mammoth evolved from the Southern Mammoth sometime between 1.8 and 1.5 million years ago. A fairly recent relook at hundreds of mammoth teeth in American museums, dispelled this long held theory. The teeth analysed show that they are incredibly similar to the Steppe Mammoth. Lolloping in herds across the cold, grassy tundra, the Steppe Mammoth reached North America, leaving a descendent, the Columbian Mammoth.
The Columbian Mammoth has thrown up more bizarre facts, questioning what we rely on as identifying a species. Palaeontologists look at the remains of animals and plants to work out the diversity of life on the planet. Most of the time these remains are just tiny parts of the whole creature. Specimens of Columbian Mammoth teeth have been analysed using their DNA which strongly suggest that this species was successfully mating with the Woolly Mammoth, leaving fertile offspring. Normally the definition of a species is a group of animals that can breed and produce fertile offspring. (A donkey and a horse can mate, but the mule is sterile.). As we have more data on more recent animals, the line of what we call a species becomes more blurred. We have seen this with recent genetic studies on Neanderthal remains showing that all non-African humans alive today have some Neanderthal DNA.
Sharing its home with other large Ice Age beasts such as giant sloths and sabre-tooth cats, the Columbian Mammoth was one of America’s true giants. After the arrival of humans to America 15,000 years ago, we see the beginning of the end of this beautiful creature. Several sites have recovered human flint implements alongside Columbian Mammoth remains, and bones showing butchery marks. Sadly, a similar story emerges with the Columbian Mammoth sustaining humans which ended the species.
The mammoth in Los Angeles (and most of North America), the Columbian Mammoth (Mammuthus columbi) (Image by Twilight Beasts)
The Pygmy Mammoth
There is one last species of mammoth. In 1856 off the coast of California, about 15 miles out, the small Channel Islands, fossils of very small mammoths were found. This was the Pygmy Mammoth (M. exilis), dating to 80,000 years ago (the third dwarf mammoth species!). Sea levels were a little lower back then, but there was still a vast gulf between the mainland and the islands: a gulf of about 12 miles. Some Columbian Mammoths actually made the journey by swimming! Probably not just on the one occasion, but a few times. Why they decided to take the plunge will never be known. But we do know that they did. Once there, the Island Rule we have seen twice already went into action. Each generation grew a little smaller.
These were not the smallest of the dwarf mammoths, but they were perhaps the most adaptive. Tiny pollen fossils in sediments and the Pygmy Mammoth’s dung show that these little beasts were not limited to one environment on the islands. The youngest fossils date to the same time as evidence for humans arriving, 13, 000 years ago. Isolated for over 60,000 years with no natural predators, the Pygmy Mammoth was vulnerable to human predation, and they too vanished into the twilight.
The third mini-mammoth, not the smallest, but still pretty darn cute. The Pygmy Mammoth (Mammuthus exilis). (Image by Twilight Beasts)
Mammoths have played a part in the lives of humans for tens of thousands of years. Cave paintings in France and Spain beautifully illustrate these creatures drawn from life. Their flesh and bones helped with our own survival. Their bones have also been used as the canvas for some of the earliest pieces of art. Within a breath of the present day the mighty mammoth has vanished forever.
Today there is a lot of attention being given to resurrecting the Woolly Mammoth. Frozen carcasses from Siberia, Asian elephant surrogates, and recreating a Pleistocene Park are splashed across the media every few months. Should we or shouldn’t we is a debate for another post. The mammoths were an incredible group and to see a living giant trundling across the barren tundra landscape, their long shaggy hair floating up with the soft gust of wind, would be a true sight to behold. Personally, we should spend our efforts on protecting the species that are with us today. The last line of an incredible Order of animals are threatened by poaching and habitat loss. If we are not careful, the beautiful elephants too will become another iconic animal our grandchildren will never see, only dream about. The mammoths had their time. Our planet is for the creatures that share it with us today.
Written by Jan Freedman (@JanFreedman)
Our posts on the Proboscidea:
The Steppe Mammoth: The first mammoth of the steppes.
Columbian Mammoth: The last trumpet of a giant.
Woolly Mammoths: Mammoths!
Cloning mammoths: Buttercup the mammoth.
Deinotherium: The Land of the Giants.
Gompothere: The lolloping shovel mouth.
Mastodon: The Nipple Tooth.
Straight Tusked Elephant: An elephant shakes a tree.
Pygmy elephants (Stegodon): Of dwarfs and dragons.
Zyglophodon: Meet Long Tusk.
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