Extinct giant dormouse, new research


An artist’s impression of the giant dormouse Leithia melitensis (left) and its nearest living relative the garden dormouse (right). Image credit: James Sadler, University of York

From the University of York in England:

Skull of two million year-old giant dormouse reconstructed

July 9, 2020

A PhD student has produced the first digital reconstruction of the skull of a gigantic dormouse, which roamed the island of Sicily around two million years ago.

In a new study, the student from Hull York Medical School, has digitally pieced together fossilised fragments from five giant dormouse skulls to reconstruct the first known complete skull of the species.

The researchers estimate that the enormous long-extinct rodent was roughly the size of a cat, making it the largest species of dormouse ever identified.

The digitally reconstructed skull is 10 cm long — the length of the entire body and tail of many types of modern dormouse.

PhD student Jesse Hennekam said: “Having only a few fossilised pieces of broken skulls available made it difficult to study this fascinating animal accurately. This new reconstruction gives us a much better understanding of what the giant dormouse may have looked like and how it may have lived.”

The enormous prehistoric dormouse is an example of island gigantism — a biological phenomenon in which the body size of an animal isolated on an island increases dramatically.

The palaeontological record shows that many weird and wonderful creatures once roamed the Italian islands. Alongside the giant dormouse, Sicily was also home to giant swans, giant owls and dwarf elephants.

Jesse’s PhD supervisor, Dr Philip Cox from the Department of Archaeology at the University of York and Hull York Medical School, said: “While island dwarfism is relatively well understood, as with limited resources on an island, animals may need to shrink to survive, the causes of gigantism are less obvious.

“Perhaps, with fewer terrestrial predators, larger animals are able to survive as there is less need for hiding in small spaces, or it could be a case of co-evolution with predatory birds where rodents get bigger to make them less vulnerable to being scooped up in talons.”

Jesse spotted the fossilised fragments of skull during a research visit to the Palermo Museum in Italy, where a segment of rock from the floor of a small cave, discovered during the construction of a motorway in northwest Sicily in the 1970s, was on display.

“I noticed what I thought were fragments of skull from an extinct species embedded in one of the cave floor segments,” Jesse said. “We arranged for the segment to be sent to Basel, Switzerland for microCT scanning and the resulting scans revealed five fragmented skulls of giant dormice present within the rock.”

The reconstruction is likely to play an important role in future research directed at improving understanding of why some small animals evolve larger body sizes on islands, the researchers say.

“The reconstructed skull gives us a better sense of whether the giant dormouse would have looked similar to its normal-sized counterparts or whether its physical appearance would have been influenced by adaptations to a specific environment,” Jesse explains.

“For example, if we look at the largest living rodent — the capybara — we can see that it has expanded in size on a different trajectory to other species in the same family.”

Jesse is also using biomechanical modelling to understand the feeding habits of the giant dormouse.

“At that size, it is possible that it may have had a very different diet to its smaller relatives,” he adds.

Prehistoric bird sculpture discovery in China


The newly discovered bird sculpture, photo  Li et al | Plos One

From PLOS ONE, 10 June 2020:

A Paleolithic bird figurine from the Lingjing site, Henan, China

Abstract

The recent identification of cave paintings dated to 42–40 ka BP in Borneo and Sulawesi highlights the antiquity of painted representations in this region. However, no instances of three-dimensional portable art, well attested in Europe since at least 40 ka BP, were documented thus far in East Asia prior to the Neolithic.

Here, we report the discovery of an exceptionally well-preserved miniature carving of a standing bird from the site of Lingjing, Henan, China. Microscopic and microtomographic analyses of the figurine and the study of bone fragments from the same context reveal the object was made of bone blackened by heating and carefully carved with four techniques that left diagnostic traces on the entire surface of the object.

Critical analysis of the site’s research history and stratigraphy, the cultural remains associated with the figurine and those recovered from the other archeological layers, as well as twenty-eight radiometric ages obtained on associated archeological items, including one provided by a bone fragment worked with the same technique recorded on the object, suggest a Late Paleolithic origin for the carving, with a probable age estimated to 13,500 years old.

The carving, which predates previously known comparable instances from this region by 8,500 years, demonstrates that three-dimensional avian representations were part of East Asian Late Pleistocene cultural repertoires and identifies technological and stylistic peculiarities distinguishing this newly discovered art tradition from previous and contemporary examples found in Western Europe and Siberia.

See also here.

Mammoth discovery in Mexico


This 28 May 2020 video says about itself:

It is a discovery that could shed some light on the hunting habits of prehistoric communities in Mexico.

Archaeologists near Mexico City have discovered the remains of about 60 mammoths and other species.

Al Jazeera’s Sara Khairat reports.

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 2019 video says about itself:

Mousterian Lithics: Multiple Neandertal Tools from Single Stone

Former experimental archaeologist Nathan Martinez demonstrates how hard hammer percussion flaking can turn a single untreated chert stone into razor-edged flake knives, a hand axe and multiple Levallois blades.

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?