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.”

South African warthog piglet resists elephant

This 8 January 2020 video from South Africa says about itself:

A young warthog refused to be pushed over by an elephant that wanted to have the waterhole for itself, he kept going back even when the elephant would try and hit him with his trumpet. This sighting was filmed in Kruger national park by Brent Schnupp.

Spectacular wildlife scenes Top Five

This 14 December 2019 video says about itself:

Most Nail-Biting Moments | Top 5 | BBC Earth

Join us as we revisit some of the tensest moments recorded on the channel. From injured elephants to a game of life and death – you won’t be able to leave the edge of your seat.

Elephant hair, how strong?

This 2016 video is called Your Hair is Strong Enough to Lift Two Elephants.

From ScienceDaily:

Study of elephant, capybara, human hair finds that thicker hair isn’t always stronger

December 11, 2019

Despite being four times thicker than human hair, elephant hair is only half as strong — that’s just one finding from researchers studying the hair strength of many different mammals. Their work, appearing in a paper publishing December 11 in the journal Matter, shows that thin hair tends to be stronger than thick hair because of the way that it breaks.

“We were very surprised by the result,” says first author Wen Yang, a nanoengineering researcher at the University of California, San Diego. “Because, intuitively, we would think thick hair is stronger. Natural materials have undergone thousands of years of evolution, so to us, these materials are very well developed. We hope to learn from nature and develop synthetic products with comparable properties.”

Previous studies have found that human hair has strength comparable to that of steel when adjusted for density. This is because of hair’s hierarchical structure: human hair is composed of an outer layer called the cuticle that wraps around an inner cortex made of many small fibers linked by chemical bonds. Within each fiber, there are even smaller fibers embedded. This structural design allows hair, which is made of proteins, to be resistant to deformation.

Yang and her team, including researchers from the Meyers and Ritchie groups at University of California, San Diego, and University of California, Berkeley, were curious if hair from other animals shares similar characteristics. They collected hair samples from eight different mammals, including humans, bears, boars, horses, capybaras, javelinas, giraffes, and elephants. These hairs vary in thickness: human hair is as thin as 80 ?m in diameter, while those of elephants and giraffes are over 350 ?m in diameter.

The researchers tied individual strands of hair to a machine that gradually pulled them apart until they broke. To their surprise, they found thin hair was able to endure greater tension before it broke compared to thick hair. This also applied to hairs from the same species. For example, thin hair from a child was stronger than thicker hair from an adult.

By studying the broken hairs using a scanning electron microscope, the team found that although most hairs share a similar structure, they broke in different ways. Hairs with a diameter greater than 200 ?m, such as those of boars, giraffes and elephants, tend to break in a normal fracture mode, a clean break similar to what would happen if a banana breaks in the middle. Hairs that are thinner than 200 ?m, such as those of humans, horses and bears, break in a shear mode. The break is uneven, like when a tree branch is snapped in a storm. The distinction in cracking path is because the structural elements in different hairs interact differently.

“Shearing is when small zig-zag cracks are formed within the material as a result of stress,” Yang says. “These cracks then propagate, and for some biological materials, the sample isn’t completely broken until the small cracks meet. If a material shears, it means it can withstand greater tension and thus is tougher than a material that experiences a normal fracture.”

“The notion of thick being weaker than thin is not unusual, and we have found that happening when studying brittle materials like metal wires,” says co-author Robert Ritchie at the University of California, Berkeley. “This is actually a statistical thing, which is a bigger piece will have a greater possibility of having a defect. It’s a bit surprising to see this in hair as hair is not a brittle material, but we think it’s because of the same reason.”

The researchers believe that their findings could help scientists design better synthetic materials. But Yang says her team’s bio-inspired material manufacture is still at its infancy. Current technologies are not yet able to create materials that are as fine as hair and have a sophisticated hierarchical structure.

“There are many challenges in synthetic materials we haven’t had a solution for, from how to manufacture very tiny materials to how to replicate the bonds between each layer as seen in natural hair,” Yang says. “But if we can create metals that have a hierarchical structure like that of hair, we could produce very strong materials, which could be used as rescue ropes and for constructions.”

Photographer meets African elephant herd

This 5 December 2019 video from Africa says about itself:

Photographer captures incredible encounter with a herd of elephants.

This was the moment wildlife enthusiast Ewan Wilson got up close and personal with a herd of giant elephants while retrieving a camera trap in the bush.

This once in a lifetime opportunity happened on November 24, while Wilson was getting footage of the elephants happily grazing when they decided it was the perfect time to investigate the truck.

Ewan told Newsflare “These incredible mammals decided to spare our lives that day. They had every right to crush me and flip the vehicle but they didn’t.

“Despite having such a young calf in the herd the alphas kept us alive.

“Please do not replicate or recreate this event in the wild. I never go out looking for these interactions as the risks involved are not worth the outcome.”

Last woolly mammoths, 4,000 years ago

This August 2014 video from London, England says about itself:

The last of the mammoths | Natural History Museum

Why did the woolly mammoth go extinct? Museum mammoths expert Professor Adrian Lister discusses what his research reveals about the cause. Find out more about Museum research into the last major extinction of large mammals.

From the University of Helsinki in Finland:

The last mammoths died on a remote island

October 7, 2019

The last woolly mammoths lived on Wrangel Island in the Arctic Ocean; they died out 4,000 years ago within a very short time. An international research team from the Universities of Helsinki and Tübingen and the Russian Academy of Sciences has now reconstructed the scenario that could have led to the mammoths‘ extinction. The researchers believe a combination of isolated habitat and extreme weather events, and even the spread of prehistoric man may have sealed the ancient giants’ fate. The study has been published in the latest edition of Quaternary Science Reviews.

During the last ice age — some 100,000 to 15,000 years ago — mammoths were widespread in the northern hemisphere from Spain to Alaska. Due to the global warming that began 15,000 years ago, their habitat in Northern Siberia and Alaska shrank. On Wrangel Island, some mammoths were cut off from the mainland by rising sea levels; that population survived another 7000 years.

The team of researchers from Finland, Germany and Russia examined the isotope compositions of carbon, nitrogen, sulfur and strontium from a large set of mammoth bones and teeth from Northern Siberia, Alaska, the Yukon, and Wrangel Island, ranging from 40,000 to 4,000 years in age. The aim was to document possible changes in the diet of the mammoths and their habitat and find evidence of a disturbance in their environment. The results showed that Wrangel Island mammoths’ collagen carbon and nitrogen isotope compositions did not shift as the climate warmed up some 10,000 years ago. The values remained unchanged until the mammoths disappeared, seemingly from the midst of stable, favorable living conditions.

This result contrasts with the findings on woolly mammoths from the Ukrainian-Russian plains, which died out 15,000 years ago, and on the mammoths of St. Paul Island in Alaska, who disappeared 5,600 years ago. In both cases, the last representatives of these populations showed significant changes in their isotopic composition, indicating changes in their environment shortly before they became locally extinct.

Earlier aDNA studies indicate that the Wrangel Island mammoths suffered mutations affecting their fat metabolism. In this study, the team found an intriguing difference between the Wrangel Island mammoths and their ice age Siberian predecessors: the carbonate carbon isotope values indicated a difference in the fats and carbohydrates in the populations’ diets. “We think this reflects the tendency of Siberian mammoths to rely on their reserves of fat to survive through the extremely harsh ice age winters, while Wrangel mammoths, living in milder conditions, simply didn’t need to,” says Dr. Laura Arppe from the Finnish Museum of Natural History Luomus, University of Helsinki, who led the team of researchers. The bones also contained levels of sulfur and strontium that suggested the weathering of bedrock intensified toward the end of the mammoth population’s existence. This may have affected the quality of the mammoths’ drinking water.

Why then did the last woolly mammoths disappear so suddenly? The researchers suspect that they died out due to short-term events. Extreme weather such as a rain-on-snow, i.e. an icing event could have covered the ground in a thick layer of ice, preventing the animals from finding enough food. That could have led to a dramatic population decline and eventually to extinction. “It’s easy to imagine that the population, perhaps already weakened by genetic deterioration and drinking water quality issues could have succumbed after something like an extreme weather event,” says professor Hervé Bocherens from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen, a co-author of the study.

Another possible factor could have been the spread of humans. The earliest archaeological evidence of humans on Wrangel Island dates to just a few hundred years after the most recent mammoth bone. The chance of finding evidence that humans hunted Wrangel Island mammoths is very small. Yet a human contribution to the extinction cannot be ruled out.

The study shows how isolated small populations of large mammals are particularly at risk of extinction due to extreme environmental influences and human behavior. An important takeaway from this is that we can help preserve species by protecting the populations that are not isolated from one another.

How mammoth poop contributes to antibiotics research: here.

Elephants, extinct and living, size comparison video

This 19 August 2019 video says about itself:

In this video we will compare the size of different elephants and mammoths, ranging from the living African bush elephant and Indian elephant to the extinct mammoths, from woolly mammoth to Palaeoloxodon namadicus.

See also here.