Columbian mammoth footprints discovery in Oregon, USA


This video from the USA says about itself:

9 February 2018

A video produced by Dean Walton, science and technology outreach librarian in the Allan Price Science Commons & Research Library, takes us on a journey above and along a mammoth trackway at a remote site in Lake County, Oregon. The site was discovered in 2014 by the UO’s Greg Retallack and excavated by a research team in 2017. The ancient path contains multiple footprints of Columbian mammoths that once roamed the region.

From the University of Oregon in the USA:

Ancient trail of Columbian mammoths uncovered in south-central Oregon

University of Oregon-led research team uncovers numerous footprints of adult, juvenile and infant elephants in a remote dry lake basin

February 12, 2018

A fossilized trackway on public lands in Lake County, Oregon, may reveal clues about the ancient family dynamics of Columbian mammoths.

Recently excavated by a team from the University of Oregon Museum of Natural and Cultural History, the Bureau of Land Management and the University of Louisiana, the trackway includes 117 footprints thought to represent a number of adults as well as juvenile and infant mammoths.

Discovered by Museum of Natural and Cultural History paleontologist Greg Retallack during a 2014 class field trip on fossils at the UO, the Ice Age trackway is the focus of a new study appearing online ahead of print in the journal Palaeogeography, Palaeoclimatology, Palaeoecology.

Retallack returned to the site with the study’s coauthors, including UO science librarian Dean Walton, in 2017. The team zeroed in on a 20-footprint track, dating to roughly 43,000 years ago, that exhibited some intriguing features.

“These prints were especially close together, and those on the right were more deeply impressed than those on the left-as if an adult mammoth had been limping,” said Retallack, also a professor in the UO Department of Earth Sciences and the study’s lead author.

But, as the study reveals, the limping animal wasn’t alone: Two sets of smaller footprints appeared to be approaching and retreating from the limper’s trackway.

“These juveniles may have been interacting with an injured adult female, returning to her repeatedly throughout the journey, possibly out of concern for her slow progress”, Retallack said. “Such behavior has been observed with wounded adults in modern, matriarchal herds of African elephants.”

The tracks were made in a layer of volcanic soil at Fossil Lake, a site first excavated by UO science professor Thomas Condon in 1876 and today administered by the Bureau of Land Management.

“America’s public lands are some of the world’s greatest outdoor laboratories. Localities such as this mammoth tracksite are unique parts of America’s heritage and indicate that there are many special sites still to be discovered,” said study co-author Brent Breithaupt, a paleontologist in the Wyoming State Office of the Bureau of Land Management.

Specimens from the 1876 Fossil Lake excavation-along with the rest of Condon’s extensive assemblage of fossils and geologic specimens-were donated to UO in the early 1900s and form the core of the museum’s Condon Fossil Collection, now under Retallack’s direction and boasting upwards of 50,000 fossil specimens.

Last month a new state law went into effect, making the UO museum Oregon’s default repository for fossils found on state lands. The museum is also a designated repository for artifacts and paleontological specimens collected from BLM-administered lands in Oregon, ensuring they are available to future generations for education and research.

As part of the 2017 study, Neffra Matthews of the BLM’s National Operations Center in Denver, helped survey, map and document the trackway using photogrammetry, which helps scientists perform accurate measurements based on land-based or aerial photographs.

“There is a vast storehouse of natural history found on BLM-managed land, and it’s exciting to work with researchers like Professor Retallack in capturing 3D data on fragile paleontological resources,” she said.

Retallack said that trace fossils such as trackways can provide unique insights into natural history.

“Tracks sometimes tell more about ancient creatures than their bones, particularly when it comes to their behavior,” he said. “It’s amazing to see this kind of interaction preserved in the fossil record.”

Elephants once roamed across much of North America. Woolly mammoths (Mammuthus primigenius) were common in Canada and Alaska. Columbian mammoths (Mammuthus columbi) occupied the region that became Washington state to South Dakota and south into Mexico. Most mammoths went extinct about 11,500 years ago, but some isolated Arctic island populations of woolly mammoth persisted until 4,000 years ago.

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Grass snakes survived Ice Age


This video from Britain says about itself:

GRASS SNAKE AND TWO ADDERS TOGETHER

THREE SNAKES TOGETHER WATCH THEM UNFURL BEFORE YOUR EYES,THIS IS NOT A COMMON SIGHT

These reptiles had been huddling together for warmth and are waking up.

From the Senckenberg Research Institute and Natural History Museum in Germany:

Cool Snake – Warmth-loving Grass Snake survived the Ice Age in Central Europe

February 9, 2018

Using genetic analyses, Senckenberg scientists have discovered that not all Grass Snakes retreated to warm southern refugia during the last Central European Ice Age. Together with a colleague from Spain, they offer first evidence for the survival of a warmth-loving, egg-laying reptile during this cold period. The study was recently published in the journal Scientific Reports.

Among the warmth-loving reptiles, the Grass Snake is generally considered a “cool” representative: Its present distribution even extends to the Siberian permafrost soils and the area around the Finnish-Russian Lake Ladoga. “However, it came as a complete surprise to all of us that this thermophilic snake actually ‘overwintered’ in Central Europe during the Pleistocene Ice Age”, explains Professor Dr. Uwe Fritz, director of the Senckenberg Natural History Collections in Dresden.

Until now it had been assumed that thermophilic reptiles survived the Ice Ages only on the southern peninsulas of Europe and spread northward once the temperatures rose again during the Holocene and the interglacial periods. Using genetic methods, Fritz, his doctoral student Carolin Kindler, and their Spanish colleague, Eva Graciá now discovered that not all of the snakes, which are widespread across Europe today, retreated to warmer, Mediterranean regions.

The team examined a total of 1,372 genetic samples of these harmless reptiles. “We closely studied different genetic lineages of the Barred Grass Snake (Natrix helvetica) and the Eastern Grass Snake (Natrix natrix)”, explains Kindler and continues, “One of the lineages of Natrix natrix survived the Ice Age in two separate refugia: one was located in the Southern Balkans, the other — unexpectedly — in Central Europe.”

As evidence, the scientists from Dresden highlight the much higher genetic diversity — compared to their more southerly relatives — of the Grass Snakes in Northern Germany and Scandinavia.

“This means that we need to rethink the model of ‘southern warm refugia’ — areas of retreat in the Mediterranean region — during the Ice Ages. It is quite possible that other heat-loving animals also withstood the cold temperatures directly ‘at home'”, adds Fritz in summary.

Mammoth discoveries in Michigan, USA


This video from the USA says about itself:

30 November 2017

University of Michigan paleontologists conducted a second excavation this week at the Chelsea-area farm where the skull, tusks and dozens of intact bones of an ice age mammoth were pulled from the ground in late 2015.

A U-M news video of the skull and two attached tusks being hoisted from the muddy excavation pit with a backhoe on October 1, 2015, has been viewed more than 875,000 times on YouTube.

From the University of Michigan in the USA:

More mammoth bones recovered from Michigan farm where skull, tusks and dozens of intact bones of an ice age mammoth were found

November 30, 2017

University of Michigan paleontologists conducted a second excavation this week at the Chelsea-area farm where the skull, tusks and dozens of intact bones of an ice age mammoth were pulled from the ground in late 2015.

A U-M news video of the skull and two attached tusks being hoisted from the muddy excavation pit with a backhoe on Oct. 1, 2015, has been viewed more than 875,000 times on YouTube.

Nothing that dramatic happened during the two-day follow-up. But 40 additional bones and bone fragments from the Bristle Mammoth were recovered, and the researchers were able to thoroughly document the site. That just wasn’t possible two years ago, in the one-day rush to get the skull and tusks out of the ground.

“This return to the Bristle site was absolutely a success. We got the kind of information that we need to do the science right, and we were also able to recover an impressive amount of additional material from this animal,” said U-M paleontologist Daniel Fisher, who led both Bristle digs and who is overseeing the analysis of the bones and the environmental samples.

“So I’m confident that as a result of this second excavation, we’ll have more insight into what happened here,” said Fisher, director of the U-M Museum of Paleontology.

Bristle’s farm deserved a second visit in part because a single radiocarbon date from one of the mammoth bones showed the animal to be more than 15,000 years old. Also, several lines of evidence point to human processing of the mammoth carcass for food.

If additional studies substantiate those preliminary findings, the Bristle Mammoth “would represent the earliest instance of human interaction with a mammoth in the eastern Great Lakes basin,” Fisher said.

The U-M team had been trying to make a return trip to Bristle’s farm for a while but needed to find a time that worked for Fisher, excavator James Bollinger and farmer James Bristle, who harvested corn from the dig site in October.

“The crops are off, so it’s really a perfect time to do it,” Bristle said Tuesday morning as Bollinger began removing soil from a site directly south of the October 2015 excavation.

“It was such a hurried thing the first time around,” said Bristle, who renamed his farm Mammoth Acres after that find. “So this is an opportunity to complete the discovery process.”

The first mammoth bones were discovered while Bristle was installing a drainage system at a low spot in one of his fields. The farmer gave U-M researchers one day to recover whatever remains they could find; after that, the drainage project and his harvest for the year needed to resume.

Bristle later donated the mammoth remains to the university, and some of them are now on display at the U-M Museum of Natural History. This week, additional bones were found in clays that were disturbed in 2015 when a sump pump was installed as part of the drainage project. The newly discovered bones will also be donated to the university, Bristle said.

During the first Bristle dig, 55 to 60 nearly complete mammoth bones were found, accounting for 30 to 40 percent of the animal’s skeletal mass. The animal was a male in its mid-40s and would have weighed about 9 tons.

In addition to the skull with teeth and tusks, most of the vertebrae and ribs were found, along with parts of the shoulder blades and the pelvis. Notably missing are the limb and foot bones and the tail vertebrae.

This week, the researchers added 40 more bones and bone fragments, including several vertebrae, skull fragments, an intact rib, part of a shoulder blade, a piece of the pelvis, and what appears to be part of the mandible.

Most of the workers in the muddy pit with Fisher were current or former U-M students. Scott Johnston, a 2017 graduate in the Department of Earth and Environmental Sciences who has worked at the U-M Museum of Natural History since he was 14, found a jagged, softball-sized fragment of the mammoth‘s skull on Wednesday.

“I knew immediately that it was skull bone because nothing else looks exactly like it,” Johnston said. “The feeling was pure euphoria.”

Nichole Lohrke was a double major in German and evolutionary anthropology two years ago when she heard about the Bristle mammoth discovery. A few months later, she went to work in Fisher’s lab, repairing the Bristle tusks and skull. She added a minor in paleontology, graduated last spring, and on Wednesday found a plum-sized piece of the animal’s skull.

“The first Bristle excavation is what inspired me to get into paleontology,” she said. “I heard about it on the news and thought, ‘That is so cool. I would love to be part of that.’ And now I’m here.”

One goal of the second Bristle excavation was to find more bones and, possibly, additional evidence of human involvement. But an even higher priority was to reconstruct the geological context of the mammoth remains, something that simply wasn’t possible during 2015’s get-what-you-can-in-a-day dig.

The Bristle bones were found about 10 feet below the current land surface, in fine-grained clays and marls from the bottom of a pond that no longer exists.

On Tuesday of this week, the researchers dug a pit just south of the October 2015 location and collected sediment samples from the layers exposed in one of the walls. They collected samples at 2-inch intervals, from a couple feet below the top of the pit wall to the gravel at its bottom, a distance of about 13 feet. The gravel at the bottom of the pit is from a time 17,000 to 18,000 years ago, when glacial ice still covered the region, Fisher said.

Organic material from some of the samples will be radiocarbon-dated. If the dates grow steadily older with increasing depth, as expected, the researchers can have increased confidence in the dates of the Bristle Mammoth bones.

Pollen grains and fungal spores will be extracted from the sediments and analyzed to help reconstruct ancient environments and to provide proper context for the mammoth find.

Spores from the Sporormiella fungus are found today in the dung of domestic livestock animals as well as wild herbivores. The spores are preserved in recognizable form for thousands of years and are used in paleoecological studies as a proxy for the abundance of ancient grazing mammals such as mammoths.

If the fungal spores are found in the various ancient sediment layers at the Bristle site, their distribution could reveal when grazing mammals were present at the site as well as the timing of their local extinction.

Pollen grains would show what types of plants were growing at the time of the Bristle Mammoth and how the vegetation mix changed over time as the climate shifted.

The oldest well-documented, published evidence for humans in Michigan is about 13,000 years ago, the age of the spear-wielding Clovis hunters. But several lines of evidence from the Bristle Mammoth, including the single radiocarbon date, imply that humans processed the carcass more than 2,000 years before the Clovis hunters arrived.

The Bristle Mammoth remains were found in pond sediments. Fisher suspects early humans butchered the carcass and placed selected portions at the bottom of the pond for storage, using boulders to anchor their meat stash.

Examination of the sediments revealed during this week’s dig suggest the pond was small, perhaps only 20 to 30 yards across, said Fisher, a professor in the Department of Earth and Environmental Sciences and in the Department of Ecology and Evolutionary Biology.

The weather was ideal for this week’s two-day dig, with sunny skies and unseasonably warm temperatures both days. Excavation costs of the second dig are being covered by Friends of the University of Michigan Museum of Paleontology, a group of avocational paleontologists associated with the university.

North American Ice Age horses, new research


Two skulls of the new genus Haringtonhippus from Nevada (upper) and Texas (lower). Credit: Photos by Eric Scott
From the University of California – Santa Cruz in the USA:

A horse is a horse, of course, of course — except when it isn’t

Analysis of ancient DNA reveals a previously unrecognized genus of extinct horses that once roamed North America

November 28, 2017

Summary: Scientists have discovered a previously unrecognized genus of extinct horses that roamed North America during the last ice age. The new findings are based on an analysis of ancient DNA from fossils of the enigmatic ‘New World stilt-legged horse‘ excavated from sites such as Natural Trap Cave in Wyoming, Gypsum Cave in Nevada, and the Klondike goldfields of Canada’s Yukon Territory.

An international team of researchers has discovered a previously unrecognized genus of extinct horses that roamed North America during the last ice age.

The new findings, published November 28 in the journal eLife, are based on an analysis of ancient DNA from fossils of the enigmatic “New World stilt-legged horse” excavated from sites such as Natural Trap Cave in Wyoming, Gypsum Cave in Nevada, and the Klondike goldfields of Canada’s Yukon Territory.

Prior to this study, these thin-limbed, lightly built horses were thought to be related to the Asiatic wild ass or onager, or simply a separate species within the genus Equus, which includes living horses, asses, and zebras. The new results, however, reveal that these horses were not closely related to any living population of horses.

Now named Haringtonhippus francisci, this extinct species of North American horse appears to have diverged from the main trunk of the family tree leading to Equus some 4 to 6 million years ago.

“The horse family, thanks to its rich and deep fossil record, has been a model system for understanding and teaching evolution. Now ancient DNA has rewritten the evolutionary history of this iconic group,” said first author Peter Heintzman, who led the study as a postdoctoral researcher at UC Santa Cruz.

“The evolutionary distance between the extinct stilt-legged horses and all living horses took us by surprise, but it presented us with an exciting opportunity to name a new genus of horse,” said senior author Beth Shapiro, professor of ecology and evolutionary biology at UC Santa Cruz.

The team named the new horse after Richard Harington, emeritus curator of Quaternary Paleontology at the Canadian Museum of Nature in Ottawa. Harington, who was not involved in the study, spent his career studying the ice age fossils of Canada’s North and first described the stilt-legged horses in the early 1970s.

“I had been curious for many years concerning the identity of two horse metatarsal bones I collected, one from Klondike, Yukon, and the other from Lost Chicken Creek, Alaska. They looked like those of modern Asiatic kiangs, but thanks to the research of my esteemed colleagues they are now known to belong to a new genus,” said Harington. “I am delighted to have this new genus named after me. ”

The new findings show that Haringtonhippus francisci was a widespread and successful species throughout much of North America, living alongside populations of Equus but not interbreeding with them. In Canada’s North, Haringtonhippus survived until roughly 17,000 years ago, more than 19,000 years later than previously known from this region.

At the end of the last ice age, both horse groups became extinct in North America, along with other large animals like woolly mammoths and saber-toothed cats. Although Equus survived in Eurasia after the last ice age, eventually leading to domestic horses, the stilt-legged Haringtonhippus was an evolutionary dead end.

“We are very pleased to name this new horse genus after our friend and colleague Dick Harington. There is no other scientist who has had greater impact in the field of ice age paleontology in Canada than Dick,” said coauthor Grant Zazula, a Government of Yukon paleontologist. “Our research on fossils such as these horses would not be possible without Dick’s life-long dedication to working closely with the Klondike gold miners and local First Nations communities in Canada’s North.”

Coauthor Eric Scott, a paleontologist at California State University San Bernardino, said that morphologically, the fossils of Haringtonhippus are not all that different from those of Equus. “But the DNA tells a fascinatingly different story altogether,” he said. “That’s what is so impressive about these findings. It took getting down to the molecular level to discern this new genus.”

Why mammoths died, new research


This video is called Mammoths of The Ice Age: Discovery Documentary 2015.

From ScienceDaily:

Male mammoths more often fell into ‘natural traps’ and died, DNA evidence suggests

November 2, 2017

Researchers who have sexed 98 woolly mammoth specimens collected from various parts of Siberia have discovered that the fossilized remains more often came from males of the species than females. They speculate that this skewed sex ratio — seven out of every ten specimens examined belonged to males — exists in the fossil record because inexperienced male mammoths more often travelled alone and got themselves killed by falling into natural traps that made their preservation more likely. The findings are reported in Current Biology on November 2.

“Most bones, tusks, and teeth from mammoths and other Ice Age animals haven’t survived,” said Love Dalen of the Swedish Museum of Natural History. “It is highly likely that the remains that are found in Siberia these days have been preserved because they have been buried, and thus protected from weathering. The new findings imply that male mammoths more often died in a way that meant their remains were buried, perhaps by falling through lake ice in winter or getting stuck in bogs.”

“We were very surprised because there was no reason to expect a sex bias in the fossil record,” added Patrícia Pecnerova, the study’s first author, also at the Swedish Museum of Natural History. “Since the ratio of females to males was likely balanced at birth, we had to consider explanations that involved better preservation of male remains.”

The researchers made the discovery in the midst of a larger, long-term effort to examine the genomes of woolly mammoth populations. For some of the analyses, they needed to know the sex of individuals. They initially set out to determine the sex of a small number of mammoths. “It became apparent that we were finding an excess of male samples, which we found very interesting,” Dalen said.

They decided to sex more samples and to examine the sex ratio of individuals collected from the Siberian mainland and from Wrangel Island, off the coast. Overall, they found, males consistently outnumbered females among their samples.

The researchers say the findings suggest that woolly mammoths lived similarly to modern elephants, with herds of females and young elephants led by an experienced adult female. In contrast, they suspect that male mammoths, like elephants, more often lived in bachelor groups or alone and engaged in more risk-taking behavior.

“Without the benefit of living in a herd led by an experienced female, male mammoths may have had a higher risk of dying in natural traps such as bogs, crevices, and lakes,” Dalen said.

The findings highlight the utility of fossil remains for making inferences about the socioecology and behavior of extinct animals, the researchers say. At the same time, they are a reminder to researchers that fossil assemblages don’t necessarily represent a random sample of a population.

The researchers say they’ll continue to study woolly mammoth genomes and those of several other extinct Ice Age mammals. They’re curious to see whether they observe the same skewed sex ratio in other species.

Saber-toothed cats’ illnesses, new research


This video from the USA is about the La Brea Tar Pits and Natural History Museum and a saber-toothed cat.

From Science News in the USA:

Surgeon aims to diagnose deformities of extinct saber-toothed cats

By Lesley Evans Ogden

9:00am, October 13, 2017

Robert Klapper has examined scores of damaged and diseased human knees, hips and shoulders. But a visit to the La Brea Tar Pits and Museum introduced the orthopedic surgeon to the suffering of an extinct cat — and a scientific mystery. In 2000, Klapper took a break from his patients at Cedars-Sinai Medical Center in Los Angeles to visit the nearby tar pits, where myriad mammals and other animals (SN: 5/17/14, p. 18) have been getting stuck for the last 40,000 years. (Yes, modern birds and insects still wander in).

After examining a museum display of broad-snouted dire wolf (Canis dirus) skulls, Klapper made a beeline for the security guard and asked to see a curator. He badgered then collections manager Chris Shaw with questions about why the skulls looked so perfect — no signs of cancers, fractures or arthritis.

“Instead of throwing me out,” Klapper says, Shaw took Klapper into the bowels of the museum and pulled out a drawer of bones from saber-toothed cats (Smilodon fatalis), one of the abundant prehistoric animals preserved in the pits about 14,000 years ago. Klapper noticed a pelvis with a surface that reminded him of a medieval mace: One hip socket was spiky with sharp edges, a telltale sign of arthritis. At the healthy hip socket, the bone was billiard ball smooth.

That kind of bone damage did not happen overnight. The arthritic animal had been disabled for years, Klapper estimated, perhaps even from birth. The surgeon asked a favor: “I’d love to get a CT scan.” Signing out the ancient cat’s pelvis, he says, was a thrill.

Paleontologists have long debated whether saber-toothed cats were solitary or social hunters. If this lame cat had been unable to hunt for years, which is what its traumatized hip bone indicated to Klapper, it could have survived only with help from other cats.

Klapper scanned that fossilized cat pelvis but left the images untouched for years, occupied with his hospital job and hosting ESPN Radio’s Weekend Warrior, a health and sports program. Now, collaborating with Emily Lindsey, a paleoecologist at La Brea, Klapper plans to use more sophisticated radiology techniques to diagnose the deformity and possibly deduce clues about the cat’s lifestyle.

It’s still early days for the revitalized project, Lindsey cautions, but “I’m really excited about it.” The museum houses some 2,000 fossils of saber-toothed cats, several of which the two plan to scan in the months ahead.

Saber-toothed kittens and other kittens


This video from Los Angeles in California in the USA says about itself:

Saber-toothed cat struts down Wilshire Blvd in L.A. and comes home to the Tar Pits!

On Sept. 5 2012, our Saber-toothed cat took a stroll down to Wilshire Blvd. to announce that Ice Age Encounters will be at the La Brea Tar Pits every Wednesday and Saturday! Our favorite Smilodon even got the CoolHaus ice cream truck to stop by with some delicious Ice Age-themed treats. Ice Age Encounters transports you to the Los Angeles of the Late Pleistocene. While on this journey, you’ll meet the extinct creatures that lived in pre-historic L.A., and witness the natural processes that preserved their remains for thousands of years. You’ll even survive a close encounter with a Saber-Toothed Cat — and meet the scientists who study its fossils at the Page Museum!

By Alan Gilman in the USA:

Saber-toothed kittens may have been born with thicker bones than other contemporary cats

The pattern of bone development for saber-toothed cats mirrors that of contemporary cats

September 28, 2017

Saber-toothed kittens may have been born with thicker bones compared to other contemporary cats, but they have a similar pattern of bone development, according to a study published September 27, 2017 in the open-access journal PLOS ONE by Katherine Long from California State Polytechnic University, USA and colleagues.

Saber-toothed cats (Smilodon fatalis) from the Pleistocene (37,000 to 9,000 years ago) have been previously recognized as having more robust skeletons compared to other wild cats. However, how and when saber-toothed cats developed these strong bones is a mystery.

To better understand the growth of Smilodon bones in comparison to a similar species, Long and colleagues measured and analyzed hundreds of bones at various stages of development from both Smilodon and the contemporary tiger-sized cat Panthera atrox in the La Brea Tar Pits museum.

The researchers found that while Smilodon bones were more robust than the Panthera bones, they did not increase in robustness with age as expected, but were born with more robust bones to begin with. They found that the growth of Smilodon bones followed a similar pattern to other primitive cat species, where the bones actually grow longer and more slender than they grow thick. This finding suggests that the growth and development of feline species is more tightly constrained than previously thought, even with species with very different bone structures.

“Saber-tooth cats had extraordinarily strong front limbs for tackling and subduing prey before they slashed their throats or bellies with their saber-like canine teeth,” says co-author Don Prothero. “Using the extraordinary collection of limb bones of saber-tooth kittens at La Brea tar pits, we found that their limbs don’t become more robust as they grew up, but instead retain the stereotypical growth pattern where the limbs grow longer more quickly than they grow thick. To compensate, saber-tooth kittens were born with unusually robust limbs and retained that pattern as they grew.”