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shunyadragon
05-14-2020, 07:24 PM
This is not new discoveries as such, but the description of the paleontological research of the earliest known beginnings of humanity in South Africa. There are two articles related to the sites in South Africa. This is the first article:



A lost world and extinct ecosystem

by Arizona State University

Archaeological sites on the far southern shores of South Africa hold the world's richest records for the behavioral and cultural origins of our species. At this location, scientists have discovered the earliest evidence for symbolic behavior, complex pyrotechnology, projectile weapons and the first use of foods from the sea.

The Arizona State University Institute of Human Origins (IHO) field study site of Pinnacle Point sits at the center of this record, both geographically and scientifically, having contributed much of the evidence for these milestones on the evolutionary road to being a modern human.

The scientists working on these sites, led by IHO Associate Director Curtis Marean, have always faced a dilemma in understanding the context of these evolutionary milestones—much of the landscape used by these ancient people is now submerged undersea and thus poorly known to us. Marean is a Foundation Professor with the ASU School of Human Evolution and Social Change and Honorary Professor with Nelson Mandela University in South Africa.

The archaeological records come from caves and rockshelters that now look out on to the sea, and in fact, walking to many of the sites today involves dodging high tides and waves. However, through most of the last 200,000 years, lowered sea levels during glacial phases, when the ice sucks up the water, exposed a vast plain. The coast was sometimes as much as 90 km distant! Our archaeological data shows that this was the prime foraging habitat for these early modern humans, and until recently, we knew nothing about.

That has now changed with the publication of 22 articles in a special issue of Quaternary Science Reviews titled "The Palaeo-Agulhas Plain: A lost world and extinct ecosystem." About ten years ago, Marean began building a transdisciplinary international team to tackle the problem of building an ecology of this ancient landscape. ASU, Nelson Mandela University, the University of Cape Town, and the University of California at Riverside anchored the research team. Funded primarily by a $1 million National Science Foundation grant to Marean, with significant funding and resources from the Hyde Family Foundations, the John Templeton Foundation, ASU, IHO, and XSEDE, they developed an entirely new way to reconstruct "paleoecologies" or ancient ecosystems.

This began with using the high-resolution South African regional climate model—running on U.S. and South African supercomputers—to simulate glacial climate conditions. The researchers used this climate output to drive a new vegetation model developed by project scientists to recreate the vegetation on this paleoscape. They then used a wide variety of studies such as marine geophysics, deep-water diving for sample collection, isotopic studies of stalagmites and many other transdisciplinary avenues of research to validate and adjust this model output. They also created a human "agent-based model" through modern studies of human foraging of plants, animals, and seafoods, simulating how ancient people lived on this now extinct paleoscape.

"Pulling the threads of all this research into one special issue illustrates all of this science," said Curtis Marean. "It represents a unique example of a truly transdisciplinary paleoscience effort, and a new model for going forward with our search to recreate the nature of past ecosystems. Importantly, our results help us understand why the archaeological records from these South African sites consistently reveal early and complex levels of human behavior and culture. The Palaeo-Agulhas Plain, when exposed, was a 'Serengeti of the South"' positioned next to some of the richest coastlines in the world. This unique confluence of food from the land and sea cultivated the complex cultures revealed by the archaeology and provided safe harbor for humans during the glacial cycles that revealed that plain and made much of the rest of the world unwelcoming to human life."

shunyadragon
05-15-2020, 06:04 AM
One thing worthy of note here is this is one of the first paleontological projects where underwater investigations are part of the project, because rising sea levels have covered much of the habitat for the early successful homo sapiens that occupied this region, and likely populated the rest of the world.

shunyadragon
05-15-2020, 07:04 PM
The second post goes into more detail into the effect of the Volcanic Tobu eruption 74,000 years ago the caused a decades long catastrophic winter based on research of the South African sites. The first culturally advanced humans known that lesd to populate the world. The genetic evidence also traces modern human origins to this region of Africa.



Researchers study how early humans thrived through volcanic winter

UTA researcher Naomi Cleghorn has participated in a Nature paper that describes how humans thrived in South Africa through the Toba volcanic eruption about 74,000 years ago, which created a decades-long volcanic winter.

"We have demonstrated that in two sites along the south coast of South Africa that may have housed the origin population for all modern humans, our ancestors thrived through this volcanic event," Cleghorn, a UTA associate professor of sociology and anthropology, said.

"This may have been the combined result of the uniquely rich resource base of the region and a highly resilient adaptation - a hunting and gathering economy wielded by a modern human with an advanced cognition and high levels of cooperation," she added.

The scientific team found microscopic glass shards that had travelled nearly 9,000 kilometers from the eruption site and landed in the archeological sediments of two sites on the south coast of South Africa. One was a rockshelter at Pinnacle Point where people lived - sleeping at night, cooking food and sharing stories around the campfire. The others were at an open-air site just nine kilometers away, a location where humans collected stone and processed it for future tool manufacture.

"Finding the shards from Toba at these two sites means that we can link the sites at a temporal precision of about two weeks and say that the people at the sites were almost certainly of the same social group, and link activities at one site to the other," Cleghorn said. "For archaeologists, that is an extraordinary result."

Cleghorn began working with the Pinnacle Point archeological project directed by Dr. Curtis Marean of Arizona State University in 2011 and was invited to collaborate on the Toba project in 2012. After working on Pinnacle Point for four years she began research at her current site at Knysna, about 80 kilometers east of Pinnacle Point.

"We know that shortly after Toba, modern humans left Africa and conquered the planet," Cleghorn added. "My work at Pinnacle Point and now at Knysna aims to develop a high-resolution chronology of human evolution and social adaptation during that time."

The Toba shards provide a very reliable and precise means to date sites and could help tie together the chronologies of many sites across Southern Africa. Once two sites were identified, the process is extending to other sites, including Knysna, Cleghorn's current dig.

Naomi Cleghorn running the total station at the Pinnacle Point 5/6 site. Credit: UTA
UTA's support was instrumental in getting Cleghorn's project started at Knysna. Cleghorn used a Research Enhancement Program grant to run the initial test excavation, which provided the evidence needed to attract external funding for the project over several years from the Leakey Foundation, National Science Foundation, Templeton Foundation and Hyde Family Foundation. The College of Liberal Arts also supported research into mineral pigment use at the Knysna site.

So far, some dozen UTA students have participated in the Knysna field project, and this year Cleghorn is taking five current or former UTA students info the field with significant funding support.

"Naomi Cleghorn's work is foundational to paleosciences and her significant funding also demonstrates the value that leading foundations give to her work," said Elizabeth Cawthon, dean of UTA's College of Liberal Arts. "It is also cross-disciplinary work linking UTA's strategic themes of global environmental impact and sustainable urban communities."

shunyadragon
05-17-2020, 05:08 AM
The genetic evidence supports the paleontological evidence for 'Out of Africa' origins of modern Homo Sapiens from South Africa.



New light on origins of modern humans
Date: March 20, 2019
Source:
University of Huddersfield
Summary: The work confirms a dispersal of Homo sapiens from southern to eastern Africa immediately preceded the out-of-Africa migration.

The Huddersfield-Minho team of geneticists, led by Professor Martin Richards at Huddersfield and Dr Pedro Soares in Braga, along with the eminent Cambridge archaeologist Professor Sir Paul Mellars, have studied the maternally-inherited mitochondrial DNA from Africans in unprecedented detail, and have identified a clear signal of a small-scale migration from South Africa to East Africa that took place at just that time, around 65,000 years ago. The signal is only evident today in the mitochondrial DNA. In the rest of the genome, it seems to have been eroded away to nothing by recombination -- the reshuffling of chromosomal genes between parents every generation, which doesn't affect the mitochondrial DNA -- in the intervening millennia.

The migration signal makes good sense in terms of climate. For most of the last few hundred years, different parts of Africa have been out of step with each other in terms of the aridity of the climate. Only for a brief period at 60,000-70,000 years ago was there a window during which the continent as a whole experienced sufficient moisture to open up a corridor between the south and the east. And intriguingly, it was around 65,000 years ago that some of the signs of symbolism and technological complexity seen earlier in South Africa start to appear in the east.

The identification of this signal opens up the possibility that a migration of a small group of people from South Africa towards the east around 65,000 years ago transmitted aspects of their sophisticated modern human culture to people in East Africa. Those East African people were biologically little different from the South Africans -- they were all modern Homo sapiens, their brains were just as advanced and they were undoubtedly cognitively ready to receive the benefits of the new ideas and upgrade. But the way it happened might not have been so very different from a modern isolated stone-age culture encountering and embracing western civilization today.

In any case, it looks as if something happened when the groups from the South encountered the East, with the upshot being the greatest diaspora of Homo sapiens ever known -- both throughout Africa and out of Africa to settle much of Eurasia and as far as Australia within the space of only a few thousand years.

Professor Mellars commented: "This work shows that the combination of genetics and archaeology working together can lead to significant advances in our understanding of the origins of Homo sapiens."