Extinct humans Homo naledi, video


This 21 May 2020 video from Britain says about itself:

Our incredible origins: The astonishing tale of Homo naledi

Lee Berger helped unearth stunning fossils of ancient human relatives in Africa. He explains why we need to rewrite our family tree.

Pleistocene South African animals and early humans


This 27 April 2019 video says about itself:

Pelorovis (“monstrous sheep”) is an extinct genus of African wild cattle.

It first appeared in the Pliocene, 2.5 million years ago, and became extinct at the end of the Late Pleistocene about 12,000 years ago or even during the Holocene, some 4,000 years ago.

Studies show that the early forms of the genus (P. turkanensis and P. oldowayensis) are close relatives, and possibly the first members, of the genus Bos.

In contrast, the late Pleistocene form (Pelorovis antiquus) seems to be a close relative of the modern African buffalo (Syncerus caffer).

Pelorovis resembled an African buffalo, although it was larger and possessed longer, curved horns.

Pelorovis probably weighed about 1,200 kilograms (2,600 lb), with the largest males attaining 2,000 kilograms (4,400 lb).

This ranks it as one of the largest bovines, and indeed ruminants ever to have lived, rivaling the extinct American long-horned bison (Bison latifrons) and the extant African giraffe (Giraffa camelopardis).

The bony cores of the horns were each about 1 meter (3.3 ft) long; when covered with keratin (which does not survive fossilization) they could have been up to twice this length.

The horns pointed away from the head, each forming a half-circle in the species Pelorovis oldowayensis and Pelorovis turkanensis.

The horns of Pelorovis antiquus were also magnificent but resembled in shape more those of the water buffalo (Bubalus).

P. antiquus was even placed in the genus Bubalus by early specialists.

Pelorovis oldowayensis was broadly the same size as modern African buffalo, but its legs were longer, and the elongated head of this species was reminiscent to those of the modern Alcelaphinae.

Pelorovis antiquus was about the same size, but it was more robust.

Pelorovis antiquus disappeared around 12,000 years ago from southern and eastern Africa. Fossil and archaeological evidence indicates that this species lived in North Africa until 4,000 years ago.

Pelorovis oldowayensis occurred in sub-Saharan Africa and disappeared 800,000 years ago.

The best fossils of Pelorovis oldowayensis are known from the Olduvai Gorge in Tanzania; a complete skeleton of Pelorovis antiquus was found near Djelfa in Algeria.

From the University of Colorado Denver in the USA:

Migration patterns reveal an Eden for ancient humans and animals

May 22, 2020

Summary: Researchers have discovered a new migration pattern (or lack of) at Pinnacle Point, a now-submerged region in South Africa. While it was first believed large omnivores would travel to follow the growth of vegetation to survive, our researcher came to a completely new conclusion through studying antelope teeth! They discovered that this region was an Eden to all living species that called it home, including the earliest humans.

Pinnacle Point, a series of archaeological sites that overlook a now-submerged section of South Africa’s coastline and one of the world’s most important localities for the study of modern human origins, was as much of an Eden for animals as it was for early humans. Jamie Hodgkins, PhD, assistant professor of anthropology at University of Colorado Denver, and her team drilled ancient herbivore teeth to find that many local animals stayed put in the ecologically rich ecosystem, which may explain why humans flourished there, too.

Home to the Earliest Modern Humans

Home to some of the richest evidence for the behavior and culture of the earliest clearly modern humans, the submerged shelf called the Palaeo-Agulhas Plain (PAP) once formed its own ecosystem. Co-author Curtis Marean, PhD, Arizona State University, has worked with teams of scientists for decades to reconstruct the locale back into the Pleistocene, the time period that spanned from 2.6 million to 11,700 years ago.

In this study, the researchers looked specifically at antelope migratory patterns at Pinnacle Point. This series of cave sites that sit on the modern South African coast offers archaeological materials from humans who were living and hunting there back to 170,000 years ago.

“During glacial cycles, the coastal shelf was exposed,” said Hodgkins. “There would have been a huge amount of land in front of the cave sites. We thought it was likely that humans and carnivores were hunting animals as they migrated east and west over the exposed shelf.”

A Lack of Migratory Pattern

Hodgkins and her team wanted to understand those migratory patterns. They studied the carbon and oxygen isotopes within the tooth enamel of many large herbivores, including Redunca, or reedbuck, a nonmigratory antelope. Tooth enamel can reveal a pattern of migration by tracking changing levels of carbon from the plants an animal eats as its teeth grow.

In general, wetter, cooler environments are home to C3 plants; hotter, drier environments are home to C4 plants. Animals like lush vegetation, which means they tend to follow the rain patterns: in this case east for summer rain (C4 grasses), and west for winter rain (C3 grasses). If animals were migrating between summer and winter rainfall zones, their tooth enamel would register that annual C3 and C4 plant rotation as a sinusoidal curve as their teeth grew.

A) Map of South Africa (SA) showing the distribution of C4 grasses associated with the percentage of summer rain from east to west along the coast, and with the winter rainfall zone in the west (modified from Vogel, 1978); B) A map of SA showing the area of the Greater Cape Floristic Region with the expanded PAP and hypothesized animals migration (i.e. It is hypothesized that animals would have been undertaking long-distance migrations between the east coast in summer rainfall zone and west coast in the winter rainfall zone)

But when Hodgkins and her team used the nonmigratory reedbuck as their control animal, they found that the enamel from its typically migratory pals — like the wildebeest, hartebeest, and springbok — showed no discernible migratory pattern. Most animals seemed happy right where they were.

“They weren’t struggling at Pinnacle Point,” says Hodgkins. “We now know that powerful river systems supplied the expanded coast, thus animals didn’t have to be migratory. It was a great location, resource-wise. During interglacials when the coast moved closer to the caves humans had shellfish and other marine resources, and when the coast expanded in glacial times hunters had access to a rich, terrestrial environment. Hunters wouldn’t need to be as mobile with all of these herbivores wandering around.”

Thriving in an Ecogeological Haven

Hodgkins’ team’s findings of this prehistoric Eden echoed another recent discovery. Seventy-four-thousand years ago, one of Earth’s largest known eruptions at Mount Toba in Sumatra, Indonesia, created a global winter, causing population crashes. In 2018, researchers from Marean’s group found that humans at Pinnacle Point not only survived, but thrived in the haven.

Hodgkins says this is just a first attempt at using isotopic data to test the hypothesis of east and west migration patterns at these sites and further research will be done.

“It is quite possible that animal migration patterns changed as the coastline moved in and out during glacial and interglacial cycles,” said Hodgkins.

Funders for this project include the National Science Foundation, the Hyde Family Foundations, and the John Templeton Foundation at the Institute of Human Origins (IHO) at Arizona State University.

How Neanderthals made bone tools


This 2016 video says about itself:

Making a Neanderthal flint stone tool | Natural History Museum [London]

Watch a flintknapper make a Levallois core and flake, an innovative stone tool developed by the Neanderthals and early Homo sapiens. Find out about human tool-making capabilities and five key features that make us human.

From the University of California – Davis in the USA:

Neanderthals were choosy about making bone tools

May 8, 2020

Evidence continues to mount that the Neanderthals, who lived in Europe and Asia until about 40,000 years ago, were more sophisticated people than once thought. A new study from UC Davis shows that Neanderthals chose to use bones from specific animals to make a tool for specific purpose: working hides into leather.

Naomi Martisius, research associate in the Department of Anthropology, studied Neanderthal tools from sites in southern France for her doctoral research. The Neanderthals left behind a tool called a lissoir, a piece of animal rib with a smoothed tip used to rub animal hides to make them into leather. These lissoirs are often worn so smooth that it’s impossible to tell which animal they came from just by looking at them.

Martisius and colleagues used highly sensitive mass spectrometry to look at residues of collagen protein from the bones. The method is called ZooMS, or Zooarchaeology by Mass Spectrometry. The technique breaks up samples into fragments that can be identified by their mass to charge ratio and used to reconstruct the original molecule.

Normally, this method would involve drilling a sample from the bone. To avoid damaging the precious specimens, Martisius and colleagues were able to lift samples from the plastic containers in which the bones had been stored and recover enough material to perform an analysis.

Favoring bovine ribs over deer

The results show that the bones used to make lissoirs mostly came from animals in the cattle family, such as bison or aurochs (a wild relative of modern cattle that is now extinct). But other animal bones from the same deposit show that reindeer were much more common and frequently hunted for food. So the Neanderthals were choosing to use only ribs from certain types of animals to make these tools.

“I think this shows that Neanderthals really knew what they were doing,” Martisius said. “They were deliberately picking up these larger ribs when they happened to come across these animals while hunting and they may have even kept these rib tools for a long time, like we would with a favorite wrench or screwdriver.”

Bovine ribs are bigger and more rigid than deer ribs, making them better suited for the hard work of rubbing skins without wearing out or breaking.

“Neanderthals knew that for a specific task, they needed a very particular tool. They found what worked best and sought it out when it was available,” Martisius said.

Blade-like tools and animal tooth pendants previously discovered in Europe, and once thought to possibly be the work of Neanderthals, are in fact the creation of Homo sapiens, or modern humans, who emigrated from Africa, finds a new analysis by an international team of researchers. Its conclusions, reported in the journal Nature, add new clarity to the arrival of Homo sapiens into Europe and to their interactions with the continent’s indigenous and declining Neanderthal population: here.

Climate scientists from the IBS Center for Climate Physics discover that, contrary to previously held beliefs, Neanderthal extinction was neither caused by abrupt glacial climate shifts, nor by interbreeding with Homo sapiens. According to new supercomputer model simulations, only competition between Neanderthals and Homo sapiens can explain the rapid demise of Neanderthals around 43 to 38 thousand years ago: here.

How insect colours evolved, new research


This 2017 video is called Amazingly Colourful Insects and Snails 🐞.

From Yale-NUS College in Singapore:

Fossil record analysis hints at evolutionary origins of insects’ structural colors

April 14, 2020

Researchers from Yale-NUS College in Singapore and University College Cork (UCC) in Ireland have analysed preserved scales from wing cases of two fossil weevils from the Late Pleistocene era (approx. 13,000 years ago) to better understand the origin of light-scattering nanostructures present in present-day insects.

The researchers, led by Yale-NUS Assistant Professor of Science (Life Sciences) Vinod Kumar Saranathan and UCC paleobiologists Drs Luke McDonald and Maria McNamara, found that the wing cases of the fossil weevils contained preserved photonic ‘diamonds’, one of the many types of crystal-like nanoscopic structure that interacts with light to produce some of the brightest and purest colours in nature.

The outer coverings of many insects comprise repeating units arranged in a crystalline formation that interact with visible light to produce structural colours, which typically have a metallic, iridescent appearance. For many of these insects, the iridescent colours perform a variety of functions including camouflage, signalling potential mates, and warning off predators. To date, the evolutionary history of these complex tissue structures has not been clearly defined. This study highlights the great potential of the fossil record as a means to unearth the evolutionary history of structural colours, not only in weevils but also in other insects, and paves the way for further research on the development of these light-scattering nanostructures and the vibrant colours they give rise to.

The researchers used powerful electron microscopes and state-of-the-art synchrotron X-ray scattering and optical modelling techniques to identify and characterise a rare 3D photonic crystal nanostructure in the fossil weevil scales — whose blue and green hues are very similar to those of modern weevils from the same genus — revealing a diamond-like arrangement. Instances of 3D nanostructures are extremely rare in the fossil record. This study marks the second time such nanostructures have been found. The only other instance of such nanostructures found in the fossil record of another weevil was also discovered by Asst Prof Saranathan and Dr McNamara.

The fact that very similar substrate-matching green colours have been maintained over hundreds of thousands of generations suggest that the same selective pressures for camouflage have been acting on these weevils. This is consistent with a recent study by Asst Prof Saranathan and weevil systematist Dr Ainsley Seago that suggests the weevils’ colours evolved initially for camouflage amongst their leafy background, before diversifying for other functions such as to signal potential mates or deter predators.

Asst Prof Saranathan, who holds a concurrent appointment at the National University of Singapore’s Department of Biological Sciences, said, “It is very interesting to discover that insects first seem to evolve complex 3D nanoscale architectures in order to escape predators by blending in with their background (usually brown or green). Only later do these colours diverge for other uses, such as signalling potential mates or as a warning to predators that the insect is not worth eating.”

Human ancestors climbed trees, new research


This December 2016 video says about itself:

The original human ancestor ‘Lucy’ was a tree-climbing champion and moved like a chimpanzee

She is one of mankind’s oldest and best-preserved ancestors and is more than three million years old.

But new analysis of the fossilised arm bones of Lucy, an early hominin, suggests she was a tree climber.

Researchers say that the relative strength of her arm bones would have placed her somewhere between a chimpanzee and a human, strengthening the evidence of our evolutionary path.

From the University of Kent in England:

Regular climbing behavior in a human ancestor

March 30, 2020

A new study led by the University of Kent has found evidence that human ancestors as recent as two million years ago may have regularly climbed trees.

Walking on two legs has long been a defining feature to differentiate modern humans, as well as extinct species on our lineage (aka hominins), from our closest living ape relatives: chimpanzees, gorillas and orangutans. This new research, based on analysis of fossil leg bones, provides evidence that a hominin species (believed to be either Paranthropus robustus or early Homo) regularly adopted highly flexed hip joints; a posture that in other non-human apes is associated with climbing trees.

These findings came from analysing and comparing the internal bone structures of two fossil leg bones from South Africa, discovered over 60 years ago and believed to have lived between 1 and 3 million years ago. For both fossils, the external shape of the bones were very similar showing a more human-like than ape-like hip joint, suggesting they were both walking on two legs. The researchers examined the internal bone structure because it remodels during life based on how individuals use their limbs. Unexpectedly, when the team analysed the inside of the spherical head of the femur, it showed that they were loading their hip joints in different ways.

The research project was led by Dr Leoni Georgiou, Dr Matthew Skinner and Professor Tracy Kivell at the University of Kent’s School of Anthropology and Conservation, and included a large international team of biomechanical engineers and palaeontologists. These results demonstrate that novel information about human evolution can be hidden within fossil bones that can alter our understanding of when, where and how we became the humans we are today.

Dr Georgiou said: ‘It is very exciting to be able to reconstruct the actual behaviour of these individuals who lived millions of years ago and every time we CT scan a new fossil it is a chance to learn something new about our evolutionary history.’

Dr Skinner said: ‘It has been challenging to resolve debates regarding the degree to which climbing remained an important behaviour in our past. Evidence has been sparse, controversial and not widely accepted, and as we have shown in this study the external shape of bones can be misleading. Further analysis of the internal structure of other bones of the skeleton may reveal exciting findings about the evolution of other key human behaviours such as stone tool making and tool use. Our research team is now expanding our work to look at hands, feet, knees, shoulders and the spine.’

Lucy’s species heralded the rise of long childhoods in hominids. Prolonged brain growth was already a feature for hominids before Homo genus members appeared: here.

A new study led by paleoanthropologists Philipp Gunz and Simon Neubauer from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reveals that Lucy’s species Australopithecus afarensis had an ape-like brain. However, the protracted brain growth suggests that — as is the case in humans — infants may have had a long dependence on caregivers: here.

Giant extinct swans of Sicily and Malta


This 8 March 2020 video says about itself:

At one point in time giant swans inhabited Sicily and Malta alongside dwarf elephants, resulting in a pretty unique ecosystem. But what were these swans – Cygnus falconeri – like when they were alive?

Siberian Ice Age horned lark discovery


This video from the USA says about itself:

A video portrait of a singing Horned Lark, gathered just before sunset near Columbia, Missouri at the University’s Bradford Farm Experimental Station. The male has a high-pitched tinkling song that cascades to a jumble at the end. At the end of the video, the male sings a more complex, extended song that goes on for nearly ten seconds before ending with the typical jumble.

© 2010 Lang Elliott

From Stockholm University in Sweden:

Frozen bird turns out to be 46,000-year-old horned lark

February 21, 2020

Scientists have recovered DNA from a well-preserved horned lark found in Siberian permafrost. The results can contribute to explaining the evolution of subspecies, as well as how the mammoth steppe transformed into tundra, forest and steppe biomes at the end of the last Ice Age.

In 2018, a well-preserved frozen bird was found in the ground in the Belaya Gora area of north-eastern Siberia. Researchers at the Centre for Palaeogenetics, a new research center at Stockholm University and the Swedish Museum of Natural History, have studied the bird and the results are now published in the scientific journal Communications Biology. The analyses reveals that the bird is a 46,000-year-old female horned lark.

“Not only can we identify the bird as a horned lark. The genetic analysis also suggests that the bird belonged to a population that was a joint ancestor of two subspecies of horned lark living today, one in Siberia, and one in the steppe in Mongolia. This helps us understand how the diversity of subspecies evolves,” says Nicolas Dussex, researcher at the Department of Zoology at Stockholm University.

The result has significance on another level as well. During the last Ice Age, the mammoth steppe spread out over northern Europe and Asia. The steppe was home to now extinct species such as the woolly mammoth and the woolly rhinoceros. According to one theory, this ecosystem was a mosaic of habitats such as steppe, tundra and coniferous forest. At the end of the last Ice Age, the mammoth steppe was divided into the biotopes we know today — tundra in the north, taiga in the middle and steppe in the south.

“Our results support this theory since the diversification of the horned lark into these subspecies seems to have happened about at the same time as the mammoth steppe disappeared,” says Love Dalén, Professor at the Swedish Museum of Natural History and research leader at the Centre for Palaeogenetics.

In the slightly longer term the researchers´ ambition is to map the complete genome of the 46,000-year-old lark and compare it with the genomes from all subspecies of horned larks.

“The new laboratory facilities and the intellectual environment at the Centre for Palaeogenetics will definitely be helpful in these analyses,” says Love Dalén.

The researchers at the Centre for Palaeogenetics have access to plenty of samples from similar findings from the same site in Siberia, including the 18,000-year-old puppy called “Dogor” which the researchers are are studying to determine if it is a wolf or a dog. Other findings include the 50,000-year-old cave lion cub “Spartak” and a partially preserved woolly mammoth.

What Ice Age mammals ate, new research


This 2012 video from the USA says about itself:

Florida’s Pleistocene Mammals

During the Pleistocene epoch, Florida was a wild place….even wilder than it is today. Mastodons, sabertooth cats and giant ground sloths roamed the peninsula in large numbers.

From the Max Planck Institute for Evolutionary Anthropology in Germany:

Reconstructing the diet of fossil vertebrates

The ratio of special zinc isotopes in dental enamel provides information about the diet of mammals in prehistoric times

February 17, 2020

Paleodietary studies of the fossil record are impeded by a lack of reliable and unequivocal tracers, currently making it impossible to determine the exact timing of dietary changes or, often, even the species involved. Scientists from the Max Planck Institute for Evolutionary Anthropology in Leipzig, the Max Planck Institute for Chemistry in Mainz and the Johannes Gutenberg University in Mainz have now tested a new method, the isotope analysis of zinc isotopes from the tooth enamel of fossil mammals. They found this method to be well suited to expand our knowledge about the diets of fossil humans and other Pleistocene mammals. The method proves especially useful when it comes to differentiating whether prehistoric mammals had mainly animal or plant-based food on the menu.

Information on what our ancestors ate is based mainly on carbon and nitrogen isotope analyses of the structural protein collagen in bones and dentin. Nitrogen isotope analysis, in particular, helps scientists determine whether animal or plant food was consumed. Since collagen, like proteins in general, is not easily conservable, this method cannot be used to examine vertebrate fossils older than about 100,000 years. This timeframe is even often reduced to only a few thousand years in arid or humid tropical regions like Africa and Asia, which are considered key regions for human evolution and are therefore of particular interest to science. New methods — such as zinc isotope analysis — are now starting to open up new research perspectives.

Zinc isotopes serve as indicators for food type consumed

The researchers analyzed the ratio of two different zinc isotopes in the dental enamel of fossil mammals that had only recently been discovered in a cave in Laos. These fossils date from the late Pleistocene, more precisely from around 13,500 to 38,400 years ago. In 2015, in the Tam Hay Marklot cave in northeastern Laos, scientists found fossils of various mammals, including water buffalos, rhinos, wild boars, deer, bears, orangutans and leopards. “The cave is located in a tropical region where organic materials such as collagen are generally poorly preserved. This makes it an ideal location for us to test whether we can determine the differences between herbivores and carnivores using zinc isotopes,” says study leader Thomas Tütken, professor at the JGU’s Institute of Geosciences.

First study with zinc isotopes on fossils shows preservation of food signatures

Zinc is ingested with food and stored as an essential trace element in the bioapatite, the mineral phase of tooth enamel. Thus, zinc has a better chance of being retained over longer periods of time than the collagen-bound nitrogen. The relevant ratio is derived from the ratio of zinc 66 to zinc 64: “On the basis of this ratio we can tell which animals are herbivores, carnivores or omnivores. This means that among the fossils we analyze, we can identify and clearly distinguish between carnivores and herbivores, while omnivores are expected to be in between,” says Nicolas Bourgon first author of the study from the Max Planck Institute for Evolutionary Anthropology and PhD student in Tütken’s research group. Lean meat contains more zinc-64 than plant food does. Carnivores, like the tiger, will have a smaller ratio of zinc-66 to zinc-64, as compared to herbivores, like the water buffalo.

In order to exclude alteration from external sources on the samples, the fossils were also examined by the team of Klaus Peter Jochum at the Max Planck Institute for Chemistry. No changes were found when comparing the concentration and distribution of zinc and other trace elements of fossil tooth enamel with those of modern animals using laser ablation ICP mass spectrometry.

Time horizon to be extended to over 100,000-year-old fossils

The zinc isotope method has now — for the first time — been successfully applied to fossils. “The zinc isotope ratios in fossil enamel from the Tam Hay Marklot cave suggest an excellent long-term conservation potential in enamel, even under tropical conditions,” summarize the authors. Zinc isotopes could thus serve as a new tool to study the diet of fossil humans and other mammals. This would open a door to the study of prehistoric and geological periods well over 100,000 years ago. In the future, the next goals are to apply this method to reconstruct human dietary behaviours. The researchers also want to find out how far back in time back in time they can go, by applying their new method to fossils of extinct mammals and dinosaurs that are millions of years old.

Prehistoric giant straight-tusked elephants, new research


This 2017 video says about itself:

Palaeoloxodon namadicus || The largest elephant recorded so far

Palaeoloxodon namadicus or the Asian straight-tusked elephant was a species of prehistoric elephant that ranged throughout Pleistocene Asia, from India (where it was first discovered) to Japan. It is a descendant of the straight-tusked elephant.

Some authorities regard it to be a subspecies of Palaeoloxodon antiquus, the straight-tusked elephant, due to extreme similarities of the tusks. Their skull structure was different from that of a modern elephant.

P. namadicus is thought to have died out around 24,000 years ago, near the end of the Pleistocene.

Several studies have attempted to estimate the size of the Asian straight-tusked elephants, as well as other prehistoric proboscideans, usually using comparisons of thigh bone length and knowledge of relative growth rates to estimate the size of incomplete skeletons.

One partial skeleton found in India in 1905 had thigh bones that likely measured 165 centimetres (5.41 ft) when complete, suggesting a total shoulder height of 4.5 metres (14.8 ft) for this individual elephant.

Two partial thigh bones were found in the 19th century and would have measured 160 cm (5.2 ft) when complete.

A fragment from the same locality was said to be almost a quarter larger; volumetric analysis then yields a size estimate of 5.2 metres (17.1 ft) tall at the shoulder and 22 tonnes (24.3 short tons) in weight. This would make P. namadicus the largest land mammal known, surpassing the largest indricotheres.

From the University of Bristol in England:

A chronicle of giant straight-tusked elephants

January 21, 2020

About 800,000 years ago, the giant straight-tusked elephant Palaeoloxodon migrated out of Africa and became widespread across Europe and Asia.

It divided into many species, with distinct types in Japan, Central Asia and Europe — even some dwarf forms as large as a small donkey on some Mediterranean islands.

In a new study by scientists in Spain, Italy and the UK, including University of Bristol PhD student Hanwen Zhang, published in the journal Quaternary Science Reviews, some order has been brought into our understanding of all these species.

The most intriguing feature of the straight-tusked elephant, apart from its absolutely enormous size, is the massive, headband-like crest on the skull roof which projects down the forehead. When the celebrated Victorian Scottish geologist Hugh Falconer studied the first fossil skull of Palaeoloxodon found in India, he remarked that the head seemed ‘so grotesquely constructed that it looks the caricature of an elephant’s head in a periwig’.

For a long time, palaeontologists thought that the European species, Palaeoloxodon antiquus, had a rather slenderly built skull roof crest; whereas the Indian species Palaeoloxodon namadicus is characterised by an extremely robust skull crest that extends near to the base of the trunk from the top of the skull.

But some Palaeoloxodon skulls, found in Italy and Germany, with almost the same exaggerated skull crest as the Indian form, led a few experts into suspecting these might all be single species.

Hanwen Zhang, who is based in Bristol’s School of Earth Sciences, said: “Just like modern elephants, Palaeoloxodon went through six sets of teeth in their lifetimes. This means we can tell the age of any individual with confidence by looking at its fossilised teeth.

“When we looked at a series of skulls from Italy, Germany and India, we found a consistent pattern: the skull crest developed from being very small, not protruding beyond the forehead in juveniles to being larger and more protruding in young adults, eventually becoming very stout in aged adults.”

The study’s lead author, Asier Larramendi, an independent researcher from Spain, added: “As I plotted various skull and limb bone measurements for these incredible prehistoric elephants, it became clear that the Indian Palaeoloxodon form a distinct group from the European ones; even in European skulls with quite pronounced crests, the skull roof never becomes as thickened as in the Indian specimens.

“This tells us we once had two separate species of these enormous elephants in Europe and India.

“Besides the funky skull roof crest, the head of the straight-tusked elephant is also remarkable for being huge, the largest of any elephant ever — some 4.5 feet from the top of the skull roof to the base of the tusk sheaths!

“Therefore, the skull crest probably evolved to provide additional attachment areas for extra neck muscles, so the animal did not fall on its head.”

Hanwen Zhang said: “Having gotten to the bottom of the antiquus/namadicus problem, it then became apparent that other fossil skull materials found in Asia and East Africa represent distinct, possibly more evolutionarily conservative species of Palaeoloxodon.

“Even in fully mature adults with the last set of teeth in place, the skull roof crest remains comparatively unpronounced. This is the case with the earliest Palaeoloxodon from Africa, some Asian species retained this condition.”