Synchrotron X-ray sheds light on some of the world’s oldest dinosaur eggs

In the most minor details, an international team of scientists led by the University of the Witwatersrand in South Africa was able to re-construct the skulls of some of the world’s oldest documented 3D dinosaur embryos by using powerful and non-destructive ESRF synchrotron technology.

The skulls evolve as the crocodiles, ducks, turtles, and Lizards today. They are in the same order The results are published in scientific reports

In an article in Scientific Reports, the University of Witwatersrand releases 3D reconstructions of the nearly 2 cm long skulls of some of the oldest dinosaur embryos in the world.

Embryos, discovered in 1976, related to the legendary South African dinosaur Massospondylus carinatus (five-meter long herbivores nestled in the Free state region 200 million years ago in the Golden Gate Highlands National Park (Free State Region, South Africa).

The scientific usefulness of the embryos was previously limited by their extremely fragile nature and tiny size. In 2015, scientists Kimi Chapelle and Jonah Choiniere, from the University of Witwatersrand, brought them to the European Synchrotron (ESRF) in Grenoble, France for scanning.

At the ESRF, an 844 meter-ring of electrons travelling at the speed of light emits high-powered X-ray beams that can be used to non-destructively scan matter, including fossils.

The embryos were scanned at an unprecedented level of detail — at the resolution of an individual bone cell. With these data in hand, and after nearly 3 years of data processing at Wits’ laboratory, the team was able to reconstruct a 3D model of the baby dinosaur skull.

“No lab CT scanner in the world can generate these kinds of data,” said Vincent Fernandez, one of the co-authors and scientists at the Natural History Museum in London (UK).

“Only with a huge facility like the ESRF can we unlock the hidden potential of our most exciting fossils. This research is a great example of a global collaboration between Europe and the South African National Research Foundation,” he adds.

Up until now, it was believed that the embryos in those eggs had died just before hatching. However, during the study, lead author Chapelle noticed similarities with the developing embryos of living dinosaur relatives (crocodiles, chickens, turtles, and lizards).

By comparing which bones of the skull were present at different stages of their embryonic development, Chapelle and co-authors can now show that the Massospondylus embryos were actually much younger than previously thought and were only at 60% through their incubation period.

The team also found that each embryo had two types of teeth preserved in its developing jaws. One set was made up of very simple triangular teeth that would have been resorbed or shed before hatching, just like geckos and crocodiles today.

The second set was very similar to those of adults and would be the ones that the embryos hatched with. “I was really surprised to find that these embryos not only had teeth but had two types of teeth. The teeth are so tiny; they range from 0.4 to 0.7mm wide. That’s smaller than the tip of a toothpick!” explains Chapelle.

The conclusion of this research is that dinosaurs developed in the egg just like their reptilian relatives, whose embryonic developmental pattern hasn’t changed in 200 million years.

“It’s incredible that in more than 250 million years of reptile evolution, the way the skull develops in the egg remains more or less the same. Goes to show — you don’t mess with a good thing!,” concludes Jonah Choiniere, professor at the University of Witwatersrand and also co-author of the study.

The team hopes to apply their method to other dinosaur embryos to estimate their level of development.

They will be looking at the rest of the skeleton of the Massospondylus embryos to see if it also shares similarities in development with today’s dinosaur relatives.

The arms and legs of the Massospondylus embryos have already been used to show that hatchlings likely walked on two legs.

‘Little Foot’ skull reveals how this more than 3 million-year-old human ancestor lived

High-resolution micro-CT scanning of the skull of the fossil specimen known as “Little Foot” has revealed some aspects of how this Australopithecus species used to live more than 3 million years ago.

The ~3.67 million-year-old fossil specimen’s meticulous excavation cleaning and testing of the skull showed the most complete Australopithecus adult first cervical vertebra yet found.

A description of the vertebra by Wits University researchers Dr. Amélie Beaudet and the Sterkfontein team was published in the Scientific Reports.

The Centre of Excellence in Palaeosciences, the International Palaeontological Trust, the National Research Foundation the University of the Witwatersrand and the French National Center for Scientific Research, through the French Institute of South Africa, support this research program.

The first cervical vertebra (or atlas) plays a crucial role in vertebrate biology. Besides acting as the connection between the head and the neck, the atlas also plays a role in how blood is supplied to the brain via the vertebral arteries.

By comparing the atlas of “Little Foot” with other fossils from South and East Africa as well as living humans and chimpanzees, the Wits University team shows that Australopithecus was capable of head movements that differ from modern humans.

“The morphology of the first cervical vertebra, or atlas, reflects multiple aspects of an organism’s life,” says Beaudet, the lead author of the study.

“In particular, the nearly complete atlas of ‘Little Foot’ has the potential to provide new insights into the evolution of head mobility and the arterial supply to the brain in the human lineage.”

The shape of the atlas determines the range of head motions while the size of the arteries passing through the vertebrae to the skull is useful for estimating blood flow supplying the brain.

“Our study shows that Australopithecus was capable of head movements that differ from us. This could be explained by the greater ability of Australopithecus to climb and move in the trees.

However, a southern African Australopithecus specimen younger than ‘Little Foot’ (probably younger by about 1 million years) may have partially lost this capacity and spent more time on the ground, like us today.”

The overall dimensions and shape of the atlas of “Little Foot” are similar to living chimpanzees. More specifically, the ligament insertions (that could be inferred from the presence and configuration of bony tubercles) and the morphology of the facet joints linking the head and the neck all suggest that “Little Foot” was moving regularly in trees.

Because “Little Foot” is so well-preserved, blood flow supply to the brain could also be estimated for the first time, using evidence from the skull and vertebrae.

These estimations demonstrate that blood flow, and thus the utilization of glucose by the brain was about three times lower than in living humans and closer to those of living chimpanzees.

“The low investment of energy into the brain of Australopithecus could be tentatively explained by a relatively small brain of the specimen (around 408cm3), a low-quality diet (low proportion of animal products) or high costs of other aspects of the biology of Australopithecus (such as upright walking). In any case, this might suggest that the human brain’s vascular system emerged much later in our history.”

Eggshell beads made by hunter-gatherers 33,000 years ago used as a social network

New U of T Scarborough research offers physical evidence that ancient hunter-gatherers were exchanging ostrich eggshell beads in order to form large-scale social networks. 

The exchange of ostrich eggshell beads is thought to be the earliest example of social networking among humans. While it’s been theorized for decades this was the case, this study offers the first hard evidence supporting the claim.

“This is evidence of a very early social innovation humans were using to help adapt to their physical environment,” says Genevieve Dewar, associate professor in the department of anthropology and one of the authors of the research.

“The exchange of ostrich eggshell beads, some dating back to the late middle stone age, offers proof that humans were using cultural tools to develop these large networks in order to reduce the risk of living in harsher environments.”  

Published in the Proceedings of the National Academy of Science (PNAS), the research looked at the archaeological evidence of ostrich eggshell beads in two sites within highland Lesotho in southern Africa.

Through isotopic analyses, Dewar and colleagues at the University of Michigan found that the practice stretched back at least 33,000 years ago, the age of the oldest beads found at the archeological sites.

The exchange of ostrich beads, which persists even today among hunter-gatherers in southern Africa’s the Kalahari Desert, is part of a system of delayed reciprocity known as Hxaro.

The purpose is to solidify relationships among groups, so if one suffers a lack of resources through drought or lack of food, they can rely on other groups living in areas of relative plenty.

“It’s a form of reciprocity that strengthens social bonds,” explains Dewar, an expert on the origins of modern human behaviour.

“If I give you a gift of an eggshell necklace, you are socially obliged to give me one in return. It works best if it’s not done right away, as it establishes a trading relationship between the two parties. Part of the social obligation includes allowing me to come and stay with you when my resources are low, and vice-versa.”

Through further isotopic analyses, the researchers found that beads were originating from at least 350 km, showing that this type of social networking was taking place on a large scale.

Since hunter-gatherers will forage up to 10 km per day looking for food, Dewar says committing so much time and resources to create a tool with no immediate practical purpose show how important the beads were to forging social bonds. 

Ostrich eggshell was used by hunter-gatherers to make beads because it’s a fairly common raw material. In fact, the beads are found in archeological sites across southern Africa. 

Dewar says it offers some clues into how Homo sapiens were able to leave Africa and essentially colonize the planet rapidly.

“Previous species, like Homo erectus, were able to leave Africa, but they didn’t adapt as successfully to very diverse environments as humans, so there are important innovations that allowed us to do this.”

She adds that anthropologists are trying to unpack these specific social innovations that humans used in order to move into areas of the world lacking in abundant resources.

“If you have a lifeline back to a place that you know is predictable and plentiful, then you are probably more willing to push on into the unknown.” 

9-Year-Old Kid Literally Stumbled on Stunning Fossils of a New Hominid

In South Africa, a young boy walking his dog has unconsciously stumbled through a pair of about 2 million years old which is now supposed to fill an integral gap in our knowledge of human evolution.

Nine-years-old Matthew Berger and his dog stumbled in a cavern close Johannesburg in 2008, in Malapa, South Africa, over the partially fossilized bones of an adult woman and a young man.

Since then, there has been much debate over whether these remains are genuinely distinct from previously discovered species.

The bones were found to be a close relative of the Homo genus and have come to be known as Australopithecus sediba (Au. Sediba) — “Australopithecus” means “southern ape.” And now, according to a new study, the remains are believed to be the bridge in human evolution between early humans and our more apelike ancestors.

Australopithecus sediba is thought to come between the 3-million-year-old apelike species known as Australopithecus afarensis (from which the famous “Lucy” specimen comes) and the “Handyman” species known as Homo habilis, who used tools 1.5 million to 2.1 million years ago.

And these latest Au. Sediba skeletons are even more complete than the famous “Lucy,” whose 1974 discovery was previously unprecedented.

“The anatomies we are seeing in Australopithecus sediba are forcing us to reassess the pathway by which we became human,” reported Jeremy DeSilva, co-author of the study.

Though some researchers have noted this discovery as indeed that of a unique species since its uncovering in 2008, this latest study illustrates precisely how Au. sediba is, in fact, distinct.

The study thoroughly describes the new species’ anatomy and has found similarities with early members of the Homo genus “suggesting a close evolutionary relationship.”

The hands of the nearly 2-million-year-old Au. sediba resemble those of Homo habilis but are not the same, which suggests that the former was also able to use tools or at the very least, had a more precise grip than that of earlier species.

Australopithecus sediba is also now believed to have walked on two feet, though it would have spent much of its time in the trees, “perhaps for foraging and protection from predators,” the study said.

And all this, remember, came from an accidental discovery.

“Imagine for a moment that Matthew stumbled over the rock and continued following his dog without noticing the fossil,” the authors wrote.

“If those events had occurred instead, our science would not know about Au. sediba, but those fossils would still be there, still encased in calcified clastic sediments, still waiting to be discovered.”