New Ice Age rhino discovery in Kazakhstan


This video says about itself:

18 August 2015

Elasmotherium” is an extinct genus of giant rhinoceros endemic to Eurasia during the Late Pliocene through the Pleistocene, documented from 2.6 Ma to as late as 50,000 years ago, possibly later, in the Late Pleistocene, an approximate span of slightly less than 2.6 million years.

Three species are recognised. The best known, “E. sibiricum”, was the size of a mammoth and is thought to have borne a large, thick horn on its forehead. This horn was used for 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. 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.

From LiveScience:

‘Unicorns’ Lumbered Across Siberia 29,000 Years Ago

by Mindy Weisberger, Senior Writer

March 29, 2016 04:24pm ET

Large, four-legged beasts, each with a single horn growing from its head, once ambled across part of western Siberia, in what is now Kazakhstan.

Sometimes referred to as “unicorns” because of their single horns, these animals were originally thought to have gone extinct 350,000 years ago. However, fossils from a new dig site place the hefty creatures in the region as recently as 29,000 years ago, according to a recent study.

In spite of their magical-sounding nickname, these bruisers share little in common with the graceful and delicate horselike creatures described in song and story and pictured in medieval tapestries. A 1923 publication by paleontologist Henry Fairfield Osborn estimated the creatures to be larger than any of the modern rhino species. Artists’ reconstructions hint at a burly build and body plan that resemble that of the animals’ extant cousins. And the beasts go by an equally cumbersome name: Elasmotherium sibiricum (ee–laz–moh–THEER–ee–um sih–BIH–rih–cum). [6 Extinct Animals That Could Be Brought Back to Life]

A well-preserved skull

The partial skull that the researchers found was well-preserved and in very good condition overall, though the teeth were missing, the scientists said. Dimensions of features in the skull fragment were considerably bigger than those in any other E. sibiricum specimen yet discovered in Eastern Europe, hinting that the skull most likely belonged to a large, older male, said study co-author Andrey Shpanski, a paleontologist at Tomsk State University in Russia.

“The dimensions of this rhino [described] today are the biggest of those described in the literature,” Shpanski said in a statement.

E. sibiricum is thought to have ranged from the Don River in southern Russia to the eastern part of Kazakhstan, and prior findings showed that the animal had long inhabited the southeastern part of the West Siberian Plain.

Other fossils found alongside the E. sibiricum skull include two upper teeth from a mammoth, the lower jaw of a steppe elephant and pieces of a bison‘s horn stem.

Dating a “unicorn”

To find out how old the fossils were, the scientists used a method known as radiocarbon dating, which they employed to analyze the amount of carbon-14 in the skull pieces. Carbon-14 is a carbon isotope, a variation of carbon with a different number of neutrons in its nucleus (14, in this case). Living plants and animals absorb carbon-14 from the atmosphere as long as they’re alive.

But once an organism dies, the carbon-14 in its body begins to decay at a regular rate that can be tracked over time, until about 60,000 years have passed and all the carbon-14 is gone. By analyzing bones to see how much carbon-14 is left, scientists can tell when the animal was still alive.

Radiocarbon dating told researchers that the E. sibiricum individual died 29,000 years ago, a dramatic divergence from previous estimates placing the species’ extinction at 350,000 years ago.

If the new calculation is correct, the “Siberian unicorn” could have crossed paths with modern humans. An earlier study suggested that humans inhabited the Siberian Arctic as far back as 45,000 years ago, based on the evidence of a butchered mammoth carcass that was likely cut up by hunters.

The new findings were published in the Feb. 2016 issue of the American Journal of Applied Sciences.

New Australopithecus fossil discovery in Kenya


This video from the USA says about itself:

Walking With Lucy | California Academy of Sciences

19 September 2013

Appearing next to a full–scale recreation of the famous “Lucy” skeleton (Australopithecus afarensis) in Tusher African Hall, this computer animation compares the distinctive gaits of a chimpanzee, A. afarensis, and modern human, highlighting the trait of upright walking that the latter two share.

From Science Daily:

Australopithecus fossils found east of the Great Rift Valley

New remains demonstrate early hominid’s adaptability

March 24, 2016

Source: Kyoto University

Summary: New fossils from the outskirts of Nairobi reveal that Australopithecus afarensis lived far eastward beyond the Great Rift Valley, demonstrating how adaptable the early hominid species were to new environments.

New fossils from Kenya suggest that an early hominid species — Australopithecus afarensis — lived far eastward beyond the Great Rift Valley and much farther than previously thought. An international team of paleontologists led by Emma Mbua of Mount Kenya University and Masato Nakatsukasa of Kyoto University report findings of fossilized teeth and forearm bone from an adult male and two infant A. afarensis from an exposure eroded by the Kantis River in Ongata-Rongai, a settlement in the outskirts of Nairobi.

“So far, all other A. afarensis fossils had been identified from the center of the Rift Valley,” explains Nakatsukasa. “A previous Australopithecus bahrelghazali discovery in Chad confirmed that our hominid ancestor’s distribution covered central Africa, but this was the first time an Australopithecus fossil has been found east of the Rift Valley. This has important implications for what we understand about our ancestor’s distribution range, namely that Australopithecus could have covered a much greater area by this age.”

A. afarensis is believed to have lived 3,700,000-3,000,000 years ago, as characterized by fossils like “Lucy” from Ethiopia.

Stable isotope analysis revealed that the Kantis region was humid, but had a plain-like environment with fewer trees compared to other sites in the Great Rift Valley where A. afaransis fossils had previously appeared. “The hominid must have discovered suitable habitats in the Kenyan highlands. It seems that A. afaransis was good at adapting to varying environments,” notes Nakatsukasa.

The team’s survey also turned up masses of mammal fossils, including a few that probably belong to new species of bovids or baboons.

The authors write that the Kantis site was first noted in a 1991 geological survey. At that time, a farmer said that he and his family had come across fossilized bones from Kantis in the 1970s, although they did not recognize their importance. Following airing of Kenyan television programs on paleontological research, locals gradually started to appreciate the fossils. Since then, Kantis and other sites have been identified thanks to fossil notifications from the local population.

The team welcomes this achievement not only for its academic implications, but also for the benefits to the local community. “Kantis is in the vicinity of Nairobi, a major city,” said Nakatsukasa. “We hope that the discovery of the new site and the fossils will aid in increasing tourism, and in improving educational awareness of the local community.”

Pregnant tyrannosaur discovered?


This video says about itself

An excerpt from the “Clash of the Dinosaurs” series episode “Extreme Survivors” featuring the mighty TYRANNOSAURUS REX produced by Discovery Channel in 2009.

By Ed Mazza in the USA:

Science Answers An Age-Old Question: How Can You Spot A Pregnant T. rex?

“We know next to nothing about sex-linked traits in extinct dinosaurs.”

03/16/2016 05:31 am ET

Scientists have discovered what they believe is a pregnant Tyrannosaurus rex — and it might even still contain dino DNA.

Tests conducted on the fossilized femur of a 68-million-year-old T. rex revealed the presence of medullary bone, or a type of bone that forms only in female birds before or during egg-laying, according to a news release from North Carolina State University.

“It’s a dirty secret, but we know next to nothing about sex-linked traits in extinct dinosaurs,” Lindsay Zanno, assistant research professor of biological sciences at the university and co-author of the new study, said in the release.

“Dinosaurs weren’t shy about sexual signaling, all those bells and whistles, horns, crests, and frills, and yet we just haven’t had a reliable way to tell males from females,” Zanno said. “Just being able to identify a dinosaur definitively as a female opens up a whole new world of possibilities.”

N.C. state paleontologist Mary Schweitzer spotted what she believed to be the medullary bone in the T. rex sample in 2005.

“All the evidence we had at the time pointed to this tissue being medullary bone,” Schweitzer, who is lead author of the new study, said in the release. “But there are some bone diseases that occur in birds, like osteopetrosis, that can mimic the appearance of medullary bone under the microscope. So to be sure we needed to do chemical analysis of the tissue.”

The new study focused on that analysis, comparing the dino bones to the medullary tissue of ostriches and chickens.

It was a match.

One test looked for a substance called keratan sulfate, which is found in medullary bone but not other types of bone.

Scientists thought this substance might not survive the passage of millions of years, but it turns out it did.

And if that can still be detected, there may be hope that a sample of dino DNA is still waiting to be found.

“Yes, it’s possible,” Lindsay Zanno told Discovery News. “We have some evidence that fragments of DNA may be preserved in dinosaur fossils, but this remains to be tested further.”

Tyrannosaur relative, new discovery


This video says about itself:

Scientists Dicover Small T. Rex Ancestor

14 March 2016

Scientists announced Monday they have discovered a new, smaller ancestor to the T. rex. The Timurlengia euotica was roughly the size of a horse and posessed many of the same features as the T. rex.

By Jacqueline Howard, Senior Science Editor, The Huffington Post in the USA:

Meet T. Rex’s Fierce, Fleet-Footed Relative

The newly discovered species is being called a missing link.

03/14/2016 03:00 pm ET

Scientists have discovered a nimble, meat-eating dinosaur with blade-like teeth that fills an important gap in Tyrannosaurus rex’s family tree.

The newly named creature, Timurlengia euotica, sheds light on how a family of dinosaurs called tyrannosaurs advanced from being small predators to clever giants at the top of the food chain — within the span of about 70 million years.

The long-legged, 600-pound T. euotica lived some 90 million years ago. It was around this time that tyrannosaurs developed impressive cognitive abilities and sharp senses, such as the ability to detect low-frequency sounds, according to a study published Monday in the Proceedings of the National Academy of Sciences.

Soon after, tyrannosaurs began to get bigger. By the late Cretaceous period, massive tyrannosaur species would emerge, such as T. rex, which lived around 66 to 68 million years ago, said Dr. Hans-Dieter Sues, the chairman of the paleobiology department at the Smithsonian’s National Museum of Natural History and a co-author of the study.

“Timurlengia has already evolved the sophisticated senses and many bone features of T. rex but was a much smaller animal,” Sues said. “The new discovery fills in a multimillion-year gap in the evolution of one particularly successful group of dinosaurs.”

Sues and Dr. Alexander Averianov, a senior scientist at the Russian Academy of Sciences, unearthed the T. euotica fossils in the Kyzylkum Desert of Uzbekistan during a series of expeditions between 1997 and 2006.

Sues and an international team of paleontologists reanalyzed the remains and found that they belonged to a previously unknown species, T. euotica, which they determined was a relative but perhaps not an ancestor of T. rex.

“As few dinosaur fossils are known from 90 million-year-old rocks, we hoped to find fossils that would tell us something about dinosaur evolution at this point in time,” Sues said. “Still, Timurlengia showed unexpected features.”

To learn more about the species and its cognitive abilities, the researchers took CT scans of T. euotica‘s fossilized brain case and used that data to build a model of its brain.

They concluded that, even though T. euotica‘s skull was much smaller than that of T. rex, its brain and senses were highly developed.

“The ancestors of T. rex would have looked a whole lot like Timurlengia, a horse-sized hunter with a big brain and keen hearing that would put us to shame,” Dr. Steve Brusatte, a paleontologist at the University of Edinburgh in Scotland who led the new research, said in a statement. “Only after these ancestral tyrannosaurs evolved their clever brains and sharp senses did they grow into the colossal sizes of T. rex. Tyrannosaurs had to get smart before they got big.”

This new research is not only noteworthy for what it teaches us about the tyrannosaurs’ family tree, but also because it could provide clues about how dinosaurs evolved when faced with a changing environment, Sues said.

“Dinosaurs have been a huge evolutionary success since they first appeared about 230 millions year ago,” he said. “Learning about their evolutionary history and how they coped with environmental changes holds important lessons for the many changes seen in today’s world.”

Fungus, oldest land fossil, discovered


This video says about itself:

Life on Earth began in Scotland… with 440mn year old fungus, scientists discover

2 March 2016

University of Cambridge scientists have discovered the origins of land-based life on the Scottish Hebridean Island of Kerrera, in the form of a primitive fungus.

Tortotubus fungus, also found in Gotland, Sweden, is said to be one of the first organisms to make its way from the sea on to land.

By Helen Briggs, BBC News in Britain:

‘Humble little fungus’ is oldest known land fossil

2 March 2016

It is smaller than a human hair, resembles a mushroom, and is thought to be the earliest fossil of a land-dwelling organism.

The fungus, which dates back 440 million years, spent its life under the ground rotting down matter.

Even the scientist who analysed it – Dr Martin Smith – admits it is a ”humble little fungus”.

But the pioneer, known as Tortotubus, could help explain how early life colonised the rocky barren Earth.

Most scientists agree that life moved from the sea to the land between 500 and 450 million years ago.

But in order for plants and animals to gain a foothold on terra firma there needed to be nutrients and soil to support them.

Fungi kick-started this process, by getting nitrogen and oxygen into the rudimentary soil.

Fossil record

Dr Smith says there were probably bacteria and algae already on land – but these are rarely preserved in the fossil record.

This makes Tortotubus probably the oldest fossil of a land-dwelling organism yet to be found.

Dr Smith told BBC News: ”It’s the first fossil of an organism that only lived on land.

”It would have broken down dead, decayed material – essentially rotted it.”

Mushroom-forming fungi

The fossilised fungus has been found in many locations, including Sweden and Scotland.

Each microfossil is shorter than a human hair is wide and has a rope-like structure similar to that of some modern-day fungi.

Scientists think that early fungi contributed to soil formation and the rotting process, thereby paving the way for flowering plants and trees,

The early land plants were not yet flowering plants or trees. These came much later.

then animals.

”During the period when this organism existed, life was almost entirely restricted to the oceans: nothing more complex than simple mossy and lichen-like plants had yet evolved on the land,” said Dr Smith, who carried out the research at the University of Cambridge but is now based at Durham University.

”But before there could be flowering plants or trees, or the animals that depend on them, the processes of rot and soil formation needed to be established.”

The research is published in the Botanical Journal of the Linnean Society.

See also here.

Placental mammals’ family tree, new research


This 2013 video from the USA says about itself:

A tiny, furry-tailed creature was the earliest ancestor of placental mammals — a widely diverse group of animals ranging from bats to humans — according to a new study by a team of international scientists, including a core group of Museum researchers. In findings published in the February 8 issue of the journal Science, the researchers analyzed the world’s largest dataset of genetic and physical traits to find that placental mammals diversified into present-day lineages much later than is commonly thought: after the extinction event 65 million years ago that eliminated non-avian dinosaurs. This finding, and the visualization of the placental ancestor — an insect-eating animal that weighed less than a pound — was made with the help of a cloud-based and publicly accessible database called MorphoBank.

MorphoBank is an initiative funded primarily by NSF with additional support from Stony Brook University, the American Museum of Natural History, the National Oceanic and Atmospheric Administration, and the National Evolutionary Synthesis Center.

From the University of Bristol in England:

15 February 2016

Rooting the family tree of placental mammals

Placental mammals consist of three main groups that diverged rapidly, evolving in wildly different directions: Afrotheria (for example, elephants and tenrecs), Xenarthra (such as armadillos and sloths) and Boreoeutheria (all other placental mammals). The relationships between them have been a subject of fierce controversy with multiple studies coming to incompatible conclusions over the last decade leading some researchers to suggest that these relationships might be impossible to resolve.

There are thus many outstanding questions such as which is the oldest sibling of the three? Did the mammals go their separate ways due to South America and Africa breaking apart? And if not, when did placentals split up?

“This has been one of the areas of greatest debate in evolutionary biology, with many researchers considering it impossible to resolve,” said lead author Dr Tarver of Bristol’s School of Earth Sciences. “Now we’ve proven these problems can be solved – you just need to analyse genome-scale datasets using models that accurately reflect genomic evolution.”

The researchers assembled the largest mammalian phylogenomic dataset ever collected before testing it with a variety of models of molecular evolution, choosing the most robust model and then analysing the data using several supercomputer clusters at the University of Bristol and the University of Texas Advanced Computing Centre. “We tested it to destruction,” said Dr Tarver. “We threw the kitchen sink at it.”

“A complication in reconstructing evolutionary histories from genomic data is that different parts of genomes can and often do give conflicting accounts of the history,” said Dr Siavash Mirarab at the University of California San Diego, USA. “Individual genes within the same species can have different histories. This is one reason why the controversy has stood so long – many thought the relationships couldn’t be resolved.”

To address the complexities of analysing large numbers of genes shared among many species, the researchers paired two fundamentally different approaches – concatenated and coalescent-based analyses – to confirm the findings. When the dust settled, the team had a specific family tree showing that Atlantogenata (containing the sibling groups of African Afrotheria and the South American Xenarthra) is the sister group to all other placentals.

Because many conflicting family trees have already been published, the team then gathered three of the most influential rivals and tested them against each other with the same model. All of the previous studies suddenly fell into line, their data agreeing with Tarver and colleagues.

With the origins of the family tree resolved, what does this mean for placental mammals? The researchers folded in another layer – a molecular clock analysis. “The molecular clock analysis uses a combination of fossils and genomic data to estimate when these lineages diverged from each other,” said author Dr Mario Dos-Reis of Queen Mary London, UK. “The results show that the afrotherians and xenarthrens diverged from one another around 90 million years ago.”

Previously, scientists thought that when Africa and South America separated from each other over 100 million years ago, they broke up the family of placental mammals, who went their separate evolutionary ways divided by geography. But the researchers found that placental mammals didn’t split up until after Africa and South America had already separated.

“We propose that South America’s living endemic Xenarthra (for exmaple, sloths, anteaters, and armadillos) colonized the island-continent via overwater dispersal,” said study author Dr Rob Asher of the University of Cambridge, UK.

Dr Asher suggests that this isn’t as difficult as you might think. Mammals are among the great adventurers of the animal kingdom, and at the time the proto-Atlantic was only a few hundred miles wide. We already know that New World monkeys crossed the Atlantic later, when it was much bigger, probably on rafts formed from storm debris. And, of course, mammals repeatedly colonised remote islands like Madagascar.

“You don’t always need to overturn the status quo to make a big impact,” said Dr Tarver. “All of the competing hypotheses had some evidence to support them – that’s precisely why it was the source of such controversy. Proving the roots of the placental family tree with hard empirical evidence is a massive accomplishment.”

###

Paper

The Interrelationships of Placental Mammals and the Limits of Phylogenetic Inference‘ by James E. Tarver, Mario dos Reis, Siavash Mirarab, Raymond J. Moran, Sean Parker, Joseph E. O’Reilly, Benjamin L. King, Mary J. O’Connell, Robert J. Asher, Tandy Warnow, Kevin J. Peterson, Philip C.J. Donoghue and Davide Pisani in Genome Biology and Evolution.

Giant bird Gastornis in Arctic, 53 million years ago


This video says about itself:

This is a World were Birds Eat Horses- (C) Walking with Beasts

The first episode depicts the warm tropical world of the early Eocene which was 16 million years after the extinction of the non-avian dinosaurs. Birds, including the giant carnivorous Gastornis, rule this world, while mammals are still very small. The setting is near the Messel pit in Germany. Due to volcanic activity, sudden bulk escapes of carbon dioxide trapped underneath lakes are a hazard. The episode centers around a Leptictidium family foraging for food. The Leptictidium is a small leaping shrew-like mammal. While the family is foraging, a female Gastornis who has been taking care of the single egg in her nest successfully hunts down a Propalaeotherium who has been slowed down by eating fermenting grapes.

Walking with Beasts thought Gastornis was carnivorous; contrary to later theories.

From Wildlife Extra:

Flightless giant bird roamed the Arctic 53m years ago

A giant, flightless bird with a head the size of a horse’s roamed the Arctic 53m years ago when the icy wilderness was more like a swamp, scientists have confirmed.

A joint study by American and Chinese institutions found that the massive beast, known as Gastornis, existed on what is now known as Ellesmere island, found above the Arctic circle. It’s estimated the bird was 6ft tall and weighed several hundred pounds.

The evidence for Gastornis’s presence in the Arctic comes from a single fossil toe bone, found by researchers in the 1970s. Scientists have now finally confirmed that the bone matches that of a fossilized Gastornis of similar age found in Wyoming.

“I couldn’t tell the Wyoming specimens from the Ellesmere specimen, even though it was found roughly 4,000km (2,500 miles) to the north,” said Prof Thomas Stidham of the Chinese Academy of Sciences in Beijing. Stidham and his colleague Jaelyn Eberle, of the University of Colorado Boulder, matched the bones through techniques such as studying where muscle attachments lay. The research has been published in Scientific Reports.

The research raises some interesting questions over the behavior of Gastornis. The giant bird may have migrated south during winters in the Arctic, where darkness envelops the region for months at a time. The species was originally thought to be a formidable carnivore but recent research suggests that Gastornis was probably a vegan, using its huge beak to munch through leaves, nuts, seeds and fruit.

Eberle said bird fossils found in the Arctic are “extremely rare” and that the researchers aren’t sure whether Gastornis lived in the area year round.

“There are some sea ducks today that spend the winter in the cold, freezing Arctic, and we see many more species of waterfowl that are only in the Arctic during the relatively warmer spring and summer months,” she said.

Canada’s Ellesmere island is the 10th largest island in the world and lies adjacent to Greenland. Riven with fjords and attached to vast aprons of ice, Ellesmere is one of the coldest, driest and most remote places on Earth. Temperatures can reach -40C (-40F) in winter.

It was a very different place 53m years ago, however, during the Eocene epoch. During this time, Antarctica was still attached to Australia and global temperatures were unusually warm, which meant the world was mostly ice-free. Ellesmere island would have been covered in the sort of cypress swamps now found much farther south in the US, with evidence that the area hosted turtles, alligators, primates and even large hippo-like and rhino-like mammals.

While apes and alligators won’t be returning to Ellesmere any time soon, the researchers said that the discovery of Gastornis provided a better understanding of the consequences of a changed climate.

“Permanent Arctic ice, which has been around for millennia, is on track to disappear,” Eberle said.

“I’m not suggesting there will be a return of alligators and giant tortoises to Ellesmere island any time soon. But what we know about past warm intervals in the Arctic can give us a much better idea about what to expect in terms of changing plant and animal populations there in the future.”