Elephants are the end of a 60 million year lineage – the last of the megaherbivores


Patrick Barkham, The Guardian

Date Published



If, just 800 generations ago, we took a summer holiday to Crete, Cyprus or Malta, we would have found familiar-looking islands, filled with the flowers and birds we can enjoy today. But bursting through the scrub would’ve been one surprise: a pygmy elephant, one metre high, one of many different elephant species that once roamed every continent apart from Australia and Antarctica.

Ecologists define elephants as a “keystone species,” without which ecosystems would be dramatically different.

The 20,000-year-old pygmy elephants of the Mediterranean islands may appear as fantastical as the woolly mammoths which still ambled across one Alaskan island just 5,600 years ago. But these animals’ lives, and deaths, take on a new pertinence today. They lived a blink of an eye ago in evolutionary time and shared the planet with modern humans. And the fate of these lost elephants, warns Prof Adrian Lister, paleobiologist at the Natural History Museum, is analogous to the troubled future facing their close relatives, the African and Asian elephants threatened with obliteration today.

“People are more likely to drive things to extinction on islands than on the mainland,” says Lister. “One of the problems with living elephants is not just that their numbers are going down and down but that their populations are very fragmented. We call it islandisation. National parks are islands today. If you’re a population of 50 elephants on a national park in Nepal, surrounded by agricultural land, you may as well be on an oceanic island in terms of population size and genetic diversity.”

When humans spread beyond Africa, they shared the planet with 42 species of terrestrial mammal weighing more than a tonne. Now only elephants, hippos and rhinos survive. The two contemporary elephant species (some scientists now say the African elephant is two distinct species, the savannah elephant and forest elephant, although debate still rages) are the last representatives of the megafauna, or megaherbivores, who have played an enormous part in shaping life on earth for far longer than Homo sapiens.

Today’s elephants belong to a lineage stretching back 60 million years, members of the order of Proboscidea – spectacular trunked mammals. They include what may have been the largest land mammal of all time, the dinosaur-dwarfing, 12-tonne Palaeoloxodon namadicus. There were “hoe-tuskers” and “shovel-tuskers”, such as Platybelodon grangeri, which were depicted by 20th century paleontologists lowering their huge shovel-like trunks into swamps to feast on marsh plants. More recently, studies of Platybelodon molars found in China’s Linxia Basin suggest they grazed rather more like the elephants we know, clamping their shovels around trees to strip off leaves and bark.

Our understanding of ancient elephants is not merely derived from old bones or teeth but footprints too, which provide a peek into their social world. The seven-million-year-old tracks of 13 four-tusked elephants, Stegotetrabelodon syrticus, were uncovered in the deserts of the United Arab Emirates. Prints of a solitary male travelling in a different direction were also discovered, indicating that different individuals pursued social or solitary existences, just as elephants do today.

Asking if Ross MacPhee has a favourite megaherbivore is “like asking me whether I love all my children,” says the curator and professor at the American Museum of Natural History (if pushed, he prefers the Megalonyx and Megatherium, ungainly giant sloths who lack any comparable modern ancestors and so their long and successful existence on the planet remains a mystery). MacPhee studies extinction, and human species’ role in the disappearance of so many historic elephants, from the woolly mammoths to the older, shaggy-coated mastodons of North America, is a contentious subject.

“Most people in my line of work agree that most of these losses were due to human actions – that humans intensively hunted these animals,” he says. But it wasn’t just Homo sapiens: most pygmy elephants disappeared from Mediterranean islands before any evidence of human occupation and woolly mammoths in far North America disappeared before people turned up. This month, new research precisely dates the disappearance of woolly mammoth from St Paul’s Island, Alaska, at 5,600 years ago. They died of thirst – because rising seas shrank the island and reduced fresh water supplies. Humans didn’t reach St Paul’s until 1787.

“People who don’t like the idea that humans did it all want to believe that it was climate change,” says MacPhee. “It’s plausible that climate change could have an impact but the trouble is that all these extinctions weren’t at the same time. Why didn’t all the elephants go at the same time like the dinosaurs did 66 million years ago? It wasn’t so much that climate change caused extinction as caused population collapses. Climate change kind of beat the crap out of these elephants. Finally humans showed up and wiped out whatever remained. I don’t personally believe that humans can have been responsible at all times and neither could the climate.”

Today’s Asian elephant can be regarded as the oldest of the surviving Proboscideans, originating in Africa before the African elephant. “You could call it the original African elephant,” laughs Vivek Menon, chair of the Asian Elephant Specialist Group. Across the world, and not just in Asia and Africa, elephants are celebrated in culture, a staple of stories for children, a rich and mighty symbol. Even scientists don’t always object to our relentless anthropomorphism of these global citizens. “The elephant is a near person,” says Menon. “Its compassion, its memory – this is a remarkably intelligent beast. As a scientist, I know that elephants come very, very close to us.”

What is less widely recognised in modern-day elephants is their talent for engineering or reshaping landscapes. Such mighty beasts always have: when the fruits of the Osage orange, a North American tree, drop to the ground, nothing eats them. The tree is one of many ecological anachronisms. Its fruit evolved to be crunched and dispersed by the mammoths and mastodons that once tramped the continent; now they have vanished, the tree struggles to spread through the landscape.

Ecologists define elephants as a “keystone species,” without which ecosystems would be dramatically different. Just like their ancestors, African elephants disperse large quantities of seed over long distances: in Congo, scientists found forest elephants disperse 345 seeds per day from 96 species, typically more than 1km from parent trees. They convert forest to scrub, damaging trees and opening up areas to smaller herbivores or sun-loving lizards, which has also been shown to help lions catch prey. Elephants’ browsing of plants can reduce the fuel loads and the intensity of wildfires. Their defecation returns nutrients to the soil more quickly than seasonal leaf loss and decay.

Being forced into smaller “islands” of protected land has caused elephants to damage some African woodlands. A decade ago, there was fierce debate in South Africa over restarting “conservation” culls to save forest habitat. Zoologist Dr Christopher O’Kane, fellow of Worcester College, Oxford, compared the browsing impact of elephants and impala and found that the long-term impact of a reasonable density of impala had a similar impact to a reasonable density elephants – culling impala could save as much woodland as culling elephants. “We don’t really need to cull elephants and no one is going to do it for the foreseeable future but it may rear its head again,” says O’Kane. “In a perfect world, the African elephant needs a lot more space than it has.”

There are big differences between elephant species but also big cultural differences in how they are viewed. In Asia there is a long tradition of taking Asian elephants into captivity and training them. The elephant-headed Hindu god Ganesh is, appropriately enough, a remover of obstacles. Elephants are prayed to every day. “It is extraordinarily helpful that our grandmothers taught us to revere the elephant,” says Menon. Despite elephants killing more than 400 people in India every year – “this is not badgers we’re talking about,” says Menon – here there are no suggestions it should be culled. The biggest challenge in conserving the Asian elephant? “Land – nothing else,” says Menon. “As Mark Twain said, ‘buy land, they are not making it anymore’. An elephant is a nomad, it has to move, you can’t settle it. There are 1.26 billion people in India and a large-bodied animal that needs to move.”

Conservation scientists have identified 101 “corridors” in India along which elephants move between core habitat, where they can feed and breed. Elephants have tramped these routes for generations but as they are blocked – by houses, roads, railways and other linear developments – so human-elephant conflict arises. “We need to secure the 101 corridors from developmental activities,” says Menon.

As human populations rise in elephants’ territory, the ability of people to share land with another big mammal will be tested more than ever, regardless of whether the poaching epidemic is quelled. There are some smart small ways to manage local conflict: scientists are helping African farmers deploy bees to prevent (bee-fearing) elephants damaging crops. Ultimately, however, scientists such as MacPhee and O’Kane say the elephant’s future will come down to numbers – of people, as well as elephants.

The fossil record provides a dramatic picture of how the pygmy elephants, straight-tusked elephants, woolly mammoths and mastodons disappeared from the northern hemisphere as the last ice age ended. Adrian Lister detects many parallels between this period of natural warming and the anthropogenic climate change of the modern age. “You get mass extinctions when you get a coincidence of factors. This is the lesson for today,” says Lister. “What is really punishing these animals – global warming, pollution, habitat destruction – is a terrible synergy of different drivers which is threatening biodiversity today.”

We don’t know how our relatives, a few hundred generations ago, took the loss of the elephants they helped drive to extinction. We see ourselves as civilised superiors and yet demonstrate no greater restraint as scientists tell us we are causing a sixth great extinction, a wiping out of non-human life on earth. Tragedy beckons for many million less visible forms of life if we can’t save the most visible. Will the last members of the great elephant family survive? If they don’t, we only have ourselves to blame.