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Ancient footprints in Saudi Arabia help researchers track human migrations out of Africa

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Sept. 18 (UPI) — Paleontologists have discovered a diverse assemblage of 120,000-year-old human and animal footprints in an ancient lake deposit in Saudi Arabia’s Nefud Desert, offering new insights into the trajectories of human migrations out of Africa, according to a study published Friday in the journal Science Advances.

A mounting body of evidence, compiled and published over the last two decades, has upended early theories that humans migrated out of Africa in one or two giant waves.

“As more and more fossils are discovered, it seems that humans repeatedly dispersed out of Africa and did so much earlier than previously thought,” study co-author Mathew John Stewart told UPI in an email.

“Precisely when, how often and under what conditions remain open questions,” said Stewart, a researcher at the Max Planck Institute for Chemical Ecology in Germany.

For answers to these questions, researchers have mostly looked to Africa and Eurasia, ignoring the Arabian Peninsula. Though it neighbors both Africa and Asia, evidence of human occupation in the region is scant.

“The area today is a hyper-arid desert, characterized by very little rainfall and large, expansive sand dunes,” Stewart said. “The conditions are not very amenable to the preservation of material and sediments. Significant erosion of sediments and the subsequent destruction of material, such as fossil remains, is unfortunately common.”

Paleoclimate data suggests that Arabia wasn’t always as dry as it was today, and a scattering of fossil discoveries has confirmed that humans were able to make forays into the Arabian interior when shifts in climate turned the peninsula’s deserts into grassland.

The ancient footprints found in the Nefud Desert, fossilized in an ancient lake deposit known as ‘Alathar’ — Arabic for “the trace” — suggests humans made one of those forays roughly 120,000 years ago.

“The age of the footprints are consistent with Homo sapiens fossils in the Levant, and suggests that there were multiple routes that humans took upon expanding beyond Africa,” study co-author Richard Clark-Wilson told UPI in an email.

“There is earlier evidence for our species moving into the Mediterranean environment of the Levant and southern Greece, but this is the earliest evidence of our species moving into a semi-arid grassland as Arabia would have been,” said Clark-Wilson, a postgraduate research student at Royal Holloway in Britain.

In addition to human footprints, researchers uncovered footprints left by elephants, horses and hippos, suggesting Homo sapiens weren’t the only species drawn to the open grasslands and water resources of northern Arabia. Research suggests it’s possible humans were following animals when they first moved into the region.

“Whats exciting about the animal footprints is that it closely ties human and animal movements around lakes in northern Arabia,” Stewart said. “Unlike most other records, footprints provide very high-resolution information, on the order of hours or days. Also, the animal footprints provide information on what the environment and ecology was like when these people were moving through the landscape.”

While the discovery of ancient footprints in Arabia suggests human movements out of Africa extended eastward into northern Arabia, Stewart said plenty of questions remain unanswered.

“Precisely what happened to these people during the more arid periods? How long did they occupy the Arabian interior? Where did they go?”



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Space agency leaders call for greater international cooperation

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NASA Astronaut Chris Cassidy, serving as commander of the Expedition 63 mission aboard the International Space Station, took these photos of Hurricane Laura as it continued to strengthen in the Gulf of Mexico on August 25. Photo courtesy of NASA | License Photo



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Male lions form coalitions to protect territory, increase mating opportunities

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Oct. 16 (UPI) — Male animals must compete with one another for food, territory and mates. Despite this, male lions prefer to work with one or more partners.

To better understand the how’s and why’s of coalition-building among lions, biologists from the Wildlife Institute of India and the University of Minnesota turned to the Asian lion, a single lion population confined to the forests of India’s Gir National Park.

In a previous study, researchers were able to show that lion pairs had greater access to mating opportunities and were better able protect their territories than solitary lions.

“However, a lack of genetic data from the population at this stage had prevented us from determining if such cooperation extended to relatives only, or whether non-kin were included as well,” Stotra Chakrabarti, a postdoctoral research associate at the University of Minnesota, said in a news release.

For the latest study, published Friday in the journal Scientific Reports, researchers combined behavioral and genetic records of known mothers, offspring and siblings to better estimate the level of relatedness between cooperating lions.

The lions of Gita don’t just form pairs. Some lions form coalitions of three or four males. Researchers found lion trios and quartets were consistently composed of brothers and cousins. Their analysis also showed more than 70 percent of pairs were formed by unrelated lions.

“Forgoing mating opportunities is generally a severe evolutionary cost, unless in doing so you help related individuals,” said study co-author Joseph Bump, associate professor at the University of Minnesota. “As a consequence, this evidence supports a conclusion that large male lion coalitions are feasible only when all partners are brothers and/or cousins.”

Researchers found larger coalitions fared best, but the fitness of individual lions, the number of possibly sired offspring, was greater among pairs.

“The results of our study show that male coalitions prosper better than loners in established lion societies and this can have crucial implications for their conservation, especially when establishing new populations through reintroductions,” said YV Jhala, principal investigator of the Gir lion project and the dean of the Wildlife Institute of India.

The integration of field observations and genetic data allowed scientists to identify new forms of coalition building, including one team of lions feature a father and sun duo.

Because siblings rarely reach maturity, researchers found larger coalitions are uncommon among Gir lions, making up just 12 to 13 percent of male teams.

Scientists also determined that among pairs, related lions weren’t more likely to support one another during fights than unrelated lions.

“This shows that kin support is not the only reason why males cooperate with each other, but kin support makes the cooperation even more beneficial,” Bump said.

Overall, the findings suggest cooperation among lions is quite complex — a topic ripe for further investigation.

“We have quantified the ultimate reasons why unrelated males team up, but it would be worthwhile to investigate other aspects of male cooperation, including how their bonds are forged in the first place, how they find compatible partners, what breaks the ice between them when they first meet and how they decide who will lead and who will follow,” lead study author Chakrabarti said.



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Ancient societies collapsed when leaders ignored the social contract

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Oct. 16 (UPI) — When ancient societies formerly ruled by principles of good governance failed, they failed hard.

According to a new study published in the journal Frontiers in Political Science, ancient autocracies were less likely to last, but suffered less dramatic failures.

To better understand the role of government on the success and longevity of ancient societies, researchers took an in-depth look at principles that guided the governments of four societies: the Roman Empire, China’s Ming Dynasty, India’s Mughal Empire and the Venetian Republic.

Because free and fair elections were rare or nonexistent during ancient times, researchers had to come up with an alternative for gauging good governance.

“You can’t really measure it by the role of elections, so important in contemporary democracies,” study co-author Gary Feinman, the MacArthur curator of anthropology at Chicago’s Field Museum, said in a news release. “You have to come up with some other yardsticks, and the core features of the good governance concept serve as a suitable measure of that.”

“They didn’t have elections, but they had other checks and balances on the concentration of personal power and wealth by a few individuals,” Feinman said. “They all had means to enhance social well-being, provision goods and services beyond just a narrow few, and means for commoners to express their voices.”

For the ruling elite, good governance was a sensible choice. Most successful empires depended on taxes and resources from local economies, and thus their leaders had to meet the basic needs of their citizens.

“There are often checks on both the power and the economic selfishness of leaders, so they can’t hoard all the wealth,” Feinman said.

Researchers found societies with governments that were reasonably responsive to their people — governments that met the definition of good governance — tended to last a bit longer than autocratic governments.

However, researchers found that when good governments turned rotten, the breakup was often uglier than the collapse of autocratic governments.

According to the study, good governments fail more dramatically because the bureaucracy is more intimately integrated with society at large.

“Social networks and institutions become highly connected, economically, socially, and politically,” Feinman said. “Whereas if an autocratic regime collapses, you might see a different leader or you might see a different capital, but it doesn’t permeate all the way down into people’s lives, as such rulers generally monopolize resources and fund their regimes in ways less dependent on local production or broad-based taxation.”

Researchers also looked at why exactly good governments fail. They found the collapse of good governments was often triggered by the rise to power of amoral leaders — leaders who ignored the social contract and abandoned their society’s ideals.

Such betrayals often precipitated or accompanied rising inequality, concentration of political power, tax evasion, crumbling infrastructure and the decline of bureaucratic institutions — a pattern researchers suggest can be observed in modern societies.

“What I see around me feels like what I’ve observed in studying the deep histories of other world regions, and now I’m living it in my own life,” said Feinman. “It’s sort of like Groundhog Day for archaeologists and historians.”

Researchers suggest their findings are a reminder that even previously successful governments and prosperous, stable societies can fail when leaders abandon a society’s core principles.

“In the cases we address, calamity could very likely have been avoided, yet, citizens and state-builders too willingly assumed that their leadership will feel an obligation to do as expected for the benefit of society,” said lead study author Richard Blanton.

“Given the failure to anticipate, the kinds of institutional guardrails required to minimize the consequences of moral failure were inadequate,” said Blanton, a professor emeritus of anthropology at Purdue University.



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