‘Global warming killed Ice Age woolly rhinos’

This 2019 video says about itself:

The History of Climate Cycles (and the Woolly Rhino) Explained

Throughout the Pleistocene Epoch, the range of the woolly rhino grew and shrank in sync with global climate. So what caused the climate — and the range of the woolly rhino — to cycle back and forth between such extremes?

From ScienceDaily:

Ancient genomes suggest woolly rhinos went extinct due to climate change, not overhunting

August 13, 2020

Summary: Although overhunting led to the demise of some prehistoric megafauna after the last ice age, a new study found that the extinction of the woolly rhinoceros may have been caused by climate change. By sequencing ancient DNA from 14 woolly rhinos, researchers found that their population remained stable and diverse until only a few thousand years before it disappeared from Siberia, when temperatures likely rose too high.

The extinction of prehistoric megafauna like the woolly mammoth, cave lion, and woolly rhinoceros at the end of the last ice age has often been attributed to the spread of early humans across the globe. Although overhunting led to the demise of some species, a study appearing August 13 in the journal Current Biology found that the extinction of the woolly rhinoceros may have had a different cause: climate change. By sequencing ancient DNA from 14 of these megaherbivores, researchers found that the woolly rhinoceros population remained stable and diverse until only a few thousand years before it disappeared from Siberia, when temperatures likely rose too high for the cold-adapted species.

“It was initially thought that humans appeared in northeastern Siberia fourteen or fifteen thousand years ago, around when the woolly rhinoceros went extinct. But recently, there have been several discoveries of much older human occupation sites, the most famous of which is around thirty thousand years old,” says senior author Love Dalén, a professor of evolutionary genetics at the Centre for Palaeogenetics, a joint venture between Stockholm University and the Swedish Museum of Natural History. “So, the decline towards extinction of the woolly rhinoceros doesn’t coincide so much with the first appearance of humans in the region. If anything, we actually see something looking a bit like an increase in population size during this period.”

To learn about the size and stability of the woolly rhinoceros population in Siberia, the researchers studied the DNA from tissue, bone, and hair samples of 14 individuals. “We sequenced a complete nuclear genome to look back in time and estimate population sizes, and we also sequenced fourteen mitochondrial genomes to estimate the female effective population sizes,” says co-first author Edana Lord, a PhD student at the Centre for Palaeogenetics.

By looking at the heterozygosity, or genetic diversity, of these genomes, the researchers were able to estimate the woolly rhino populations for tens of thousands of years before their extinction. “We examined changes in population size and estimated inbreeding,” says co-first author Nicolas Dussex, a postdoctoral researcher at the Centre for Palaeogenetics. “We found that after an increase in population size at the start of a cold period some 29,000 years ago, the woolly rhino population size remained constant and that at this time, inbreeding was low.”

This stability lasted until well after humans began living in Siberia, contrasting the declines that would be expected if the woolly rhinos went extinct due to hunting. “That’s the interesting thing,” says Lord. “We actually don’t see a decrease in population size after 29,000 years ago. The data we looked at only goes up to 18,500 years ago, which is approximately 4,500 years before their extinction, so it implies that they declined sometime in that gap.”

The DNA data also revealed genetic mutations that helped the woolly rhinoceros adapt to colder weather. One of these mutations, a type of receptor in the skin for sensing warm and cold temperatures, has also been found in woolly mammoths. Adaptations like this suggest the woolly rhinoceros, which was particularly suited to the frigid northeast Siberian climate, may have declined due to the heat of a brief warming period, known as the Bølling-Allerød interstadial, that coincided with their extinction towards the end of the last ice age.

“We’re coming away from the idea of humans taking over everything as soon as they come into an environment, and instead elucidating the role of climate in megafaunal extinctions,” says Lord. “Although we can’t rule out human involvement, we suggest that the woolly rhinoceros’ extinction was more likely related to climate.”

The researchers hope to study the DNA of additional woolly rhinoceroses that lived in that crucial 4,500-year gap between the last genome they sequenced and their extinction. “What we want to do now is to try to get more genome sequences from rhinos that are between eighteen and fourteen thousand years old, because at some point, surely they must decline,” says Dalén. The researchers are also looking at other cold-adapted megafauna to see what further effects the warming, unstable climate had. “We know the climate changed a lot, but the question is: how much were different animals affected, and what do they have in common?”

This work was supported by FORMAS, the Swiss National Science Foundation, the Carl Tryggers Foundation, the European Research Council Consolidator Award, and the Knut and Alice Wallenberg Foundation.

Oxpeckers warn black rhinos against danger

This 2017 video from Africa is called Black Rhino & Oxpeckers; A cleaning service.

And the birds do more for the rhino than just cleaning.

From ScienceDaily:

Black rhinos eavesdrop on the alarm calls of hitchhiking oxpeckers to avoid humans

April 9, 2020

In Swahili, red-billed oxpeckers are called Askari wa kifaru, or “the rhino’s guard”. Now, a paper appearing April 9 in the journal Current Biology suggests that this indigenous name rings true: red-billed oxpeckers may act as a first line of defense against poachers by behaving like sentinels, sounding an alarm to potential danger. By tracking wild black rhinos, researchers found that those carrying oxpeckers were far better at sensing and avoiding humans than those without the hitchhiking bird.

While conservation efforts have rebounded the critically endangered black rhino’s numbers, poaching remains a major threat. “Although black rhinos have large, rapier-like horns and a thick hide, they are as blind as a bat. If the conditions are right, a hunter could walk within five meters of one, as long as they are downwind,” says Roan Plotz (@RoanPlotz), a lecturer and behavioral ecologist at Victoria University, Australia., who co-authored the paper with ecological scientist Wayne Linklater (@PolitEcol) of California State University — Sacramento. Oxpeckers, which are known to feed on the ticks and lesions found on the rhino’s body, may make up for the rhino’s poor eyesight by calling out if they detect an approaching human.

To study the role that oxpeckers might play, Plotz and his team recorded the number of oxpeckers on two groups of the rhinos they encountered. Rhinos tagged with radio transmitters — which allowed researchers to track them while evading detection from oxpeckers — carried the bird on their backs more than half the time. The untagged black rhinos they found, on the other hand, carried no oxpeckers most of the time — suggesting that other untagged rhinos that carried the birds might have avoided encountering the researchers altogether. “Using the differences we observed between oxpeckers on the tagged versus untagged rhinos, we estimated that between 40% and 50% of all possible black rhino encounters were thwarted by the presence of oxpeckers,” says Plotz.

Even when the researchers were able to locate the tagged rhinos, the oxpeckers’ alarm calls still appeared to play a role in predator defense. The field team ran a “human approach” experiment, where one researcher would walk towards the rhino from crosswind while a colleague recorded the rhino’s behavior. The field team recorded the number of oxpecker carried, the rhinos’ behavior upon approach, and the distance of the researcher when either the rhinos became vigilant or, if undetected, it became unsafe to get any closer.

“Our experiment found that rhinos without oxpeckers detected a human approaching only 23% of the time. Due to the bird’s alarm call, those with oxpeckers detected the approaching human in 100% of our trials and at an average distance of 61 meters — nearly four times further than when rhinos were alone. In fact, the more oxpeckers the rhino carried, the greater the distance at which a human was detected,” he says. He adds that these improved detection and distance estimates may even be conservative, because they don’t take into account the untagged rhinos carrying oxpeckers that the team could not detect.

When a rhino perceived the oxpecker alarm call, it nearly always re-oriented itself to face downwind — their sensory blind spot. “Rhinos cannot smell predators from downwind, making it their most vulnerable position. This is particularly true from humans, who primarily hunt game from that direction,” says Plotz.

Taken together, these results suggest that oxpeckers are effective companions that enable black rhinos to evade encounters with people and facilitate effective anti-predator strategies once found. Some scientists even hypothesize that oxpeckers evolved this adaptive behaviour as a way to protect their source of food: the rhinos.

“Rhinos have been hunted by humans for tens of thousands of years, but the species was driven to the brink of extinction over the last 150 years. One hypothesis is that oxpeckers have evolved this cooperative relationship with rhinos relatively recently to protect their food source from human overkill,” says Plotz.

Despite this closely tied relationship, oxpecker populations have significantly declined, even becoming locally extinct in some areas. As a result, most wild black rhino populations now live without oxpeckers in their environment. But based on the findings in this study, reintroducing the bird back into rhino populations may bolster conservation efforts. “While we do not know that reintroducing the birds would significantly reduce hunting impacts, we do know oxpeckers would help rhinos evade detection, which on its own is a great benefit,” says Plotz.

Plotz says that these findings, inspired by a Swahili name, also highlight the importance of local knowledge. “We too often dismiss the importance of indigenous people and their observations. While western science has been incredibly useful, there are many insights we can learn from indigenous communities.”

Sumatran rhinos, video

This 7 April 2020 video says about itself:

The Sumatran rhino is the smallest rhinoceros species in the world, and one of the world’s most endangered large mammals. In this rare encounter with a mother and calf, you can get up close to these amazing creatures at bath time.

Biggest 15 rhinoceros species, video

This 4 March 2020 video says about itself:

15 Largest Rhino Species to Ever Exist

A rhinoceros, commonly abbreviated to rhino, is one of any five extant species of odd-toed ungulates in the family Rhinocerotidae, as well as any of the numerous extinct species therein. Two of the extant species are native to Africa, and three to Southern Asia. The term “rhinoceros” is often more broadly applied to now-extinct species of the superfamily Rhinocerotoidea.

Rhino and calf in South Africa

This 31 January 2020 video from South Africa says about itself:

Daniel and his guests had a wonderful sighting of four rhinos – a mom and calf as well as a sub adult female and male! Mom and calf passed by and had a quick sniff before heading off for the day. What a sight!

Saving northern white rhinos with new technology?

This 5 October 2019 video says about itself:

Planet SOS: New technology can save rare rhino

Scientists are developing a robotic tool which can save one of the world’s rarest creatures.

They say an unprecedented wave of wildlife extinction is underway because of global warming, a loss of habitat and poaching.

They are trying to save some critically-endangered species, including the Northern White Rhino, which has been hunted to obliteration.

The project aims to produce a self-sustaining herd of Northern White Rhinos, first in captivity and then returned to the wild in Africa.

Al Jazeera’s Rob Reynolds reports from Escondido city in California.

Rhinoceros calf in trouble, video

This 5 July 2019 video from Sabi Sabi nature reserve in South Africa is called This rhino calf found itself in a spot of bother…

Woolly rhinos and ice ages, video

This 30 May 2019 video says about itself:

The History of Climate Cycles (and the Woolly Rhino) Explained

Throughout the Pleistocene Epoch, the range of the woolly rhino grew and shrank in sync with global climate. So what caused the climate — and the range of the woolly rhino — to cycle back and forth between such extremes?

Giant rhinoceros survived Ice Age longer than thought

This 22 March 2018 video says about itself:

Elasmotherium Was A Mammoth Sized Rhino from Eurasia

Elasmotherium (“Thin Plate Beast”), also known as the Siberian Unicorn or Steppe Rhinoceros, is an extinct genus of rhinoceros endemic to Eurasia. It lived during the Late Pliocene through the Pleistocene, documented from 2.6 Ma to as late as 29,000 years ago in the Late Pleistocene.

In March 2016, the discovery of a skull in Kazakhstan granted a new estimated time period to when Elasmotherium roamed the earth. The prior estimate was 350,000 years ago, now being reduced to 29,000 years ago. Three species are recognised (some say four).

The best known, E. sibiricum was the size of a mammoth and is thought to have borne a large, thick horn on its forehead. The main difference from other rhinos was the large domed protuberance on the forehead, which was probably a 1.5 meter long and thick horn. Theories about the function of this horn include defense, attracting mates, driving away competitors, sweeping snow from the grass in winter and digging for water and plant roots.

Like all rhinoceroses, elasmotheres were herbivorous. Elasmotherium was a grazer as apparent from tooth wear and morphology. This animal specialized in feeding on grass and underground parts of plants, coastal rivers and lakes, such as highly starchy rhizomes of sedges, cattail and reed.

Unlike any others, its high-crowned molars were ever-growing. Its legs were longer than those of other rhinos and were adapted for galloping, giving it a horse-like gait.

Elasmotherium was the largest member of the family of rhinos that lived from the Pliocene to Pleistocene epochs. It was 6 metres long, 2.5 metres in height and weigh up to 5 tons.

E. caucasicum … reached at least 5 m (16 ft) in body length with an estimated mass of 3.6–4.5 tonnes (4–5 short tons), based on isolated molars that significantly exceed those known from the Siberian species.

Elasmotherium legs are sufficiently like those of the White Rhino to hypothesize a similar gait even though Elasmotherium weighed 4.5-5 ton. Various theories of Elasmothere morphology, nutrition and habits have been the cause of wide variation in reconstruction. Some show the beast trotting like a horse with a horn; others hunched over with head to the ground, like a bison, and still others immersed in swamps like a hippopotamus.

The largest of all the prehistoric rhinoceroses of the Pleistocene epoch, Elasmotherium was a truly massive piece of megafauna, and all the more imposing thanks to its thick, shaggy coat of fur (this mammal was … related to Coelodonta, also known as the “woolly rhino“) and the huge horn on the end of its snout. This horn, which was made of keratin (the same protein as human hair), may have reached five or six feet in length—and if Elasmotherium survived into historical times, it’s possible that early humans glimpsing this huge, strange beast may have been inspired to create the legend of the unicorn.

From Nature Ecology and Evolution, 26 November 2018:

Evolution and extinction of the giant rhinoceros Elasmotherium sibiricum sheds light on late Quaternary megafaunal extinctions

Abstract

Understanding extinction events requires an unbiased record of the chronology and ecology of victims and survivors.

The rhinoceros Elasmotherium sibiricum, known as the ‘Siberian unicorn’, was believed to have gone extinct around 200,000 years ago—well before the late Quaternary megafaunal extinction event.

However, no absolute dating, genetic analysis or quantitative ecological assessment of this species has been undertaken. Here, we show, by accelerator mass spectrometry radiocarbon dating of 23 individuals, including cross-validation by compound-specific analysis, that E. sibiricum survived in Eastern Europe and Central Asia until at least 39,000 years ago, corroborating a wave of megafaunal turnover before the Last Glacial Maximum in Eurasia, in addition to the better-known late-glacial event.

Stable isotope data indicate a dry steppe niche for E. sibiricum and, together with morphology, a highly specialized diet that probably contributed to its extinction.

We further demonstrate, with DNA sequencing data, a very deep phylogenetic split between the subfamilies Elasmotheriinae and Rhinocerotinae that includes all the living rhinoceroses, settling a debate based on fossil evidence and confirming that the two lineages had diverged by the Eocene. As the last surviving member of the Elasmotheriinae, the demise of the ‘Siberian unicorn’ marked the extinction of this subfamily.

Rhino interrupts lion couple

This 9 August 2018 video from Africa is called Rhino interrupts lion couple.