The Times Australia
The Times World News

.

Ancient humans may have paused in Arabia for 30,000 years on their way out of Africa

  • Written by Ray Tobler, Postdoctoral fellow, Australian National University
Ancient humans may have paused in Arabia for 30,000 years on their way out of Africa

Most scientists agree modern humans developed in Africa, more than 200,000 years ago, and that a great human diaspora across much of the rest of the world occurred between perhaps 60,000 and 50,000 years ago.

In new research published[1] in Proceedings of the National Academies of Sciences, we have uncovered dozens of distinctive historical changes in the human genome to reveal a new chapter in this story.

Our work suggests there may have been a previously unknown phase of humanity’s great migration: an “Arabian standstill” of up to 30,000 years in which humans settled in and around the Arabian Peninsula. These humans slowly adapted to life in the region’s colder climate before venturing to Eurasia and beyond.

The legacy of these adaptations still lingers. Under modern conditions, many genetic changes from this period are linked to diseases including obesity, diabetes, and cardiovascular disorders.

History in our genomes

Since the first human genome was published in 2000, the amount of human genomic data available has grown exponentially. These rapidly growing datasets contain traces of key events in human history. Researchers have been actively developing new techniques to find those traces.

When ancient humans left Africa and moved around the globe, they likely met new environments and challenges. New pressures would have led to adaptation and genetic changes. These changes would subsequently have been inherited by modern humans.

Previous research[2] on genomic data shows ancient humans most likely left Africa and spread across the planet between 60,000 and 50,000 years ago.

However, we still don’t know much about genetic adaptations during this crucial time period.

Ancient adaptation events

Our team of evolutionary and medical researchers has shed new light on this period. By studying both ancient and modern genomes, we have shown genetic selection was probably an important facilitator of this ancient human diaspora.

Using ancient human genomes makes it possible to recover evidence of past events[3] in which specific genetic variants were strongly favoured over others and swept through a population. These “hard sweep” events are surprisingly rare in modern human genomes, most likely because their traces have been erased or distorted by subsequent mixing between populations.

Read more: Ancient DNA reveals a hidden history of human adaptation[4]

However, in earlier work[5] we identified 57 regions in the human genome where an initially rare beneficial genetic variant effectively replaced an older variant in ancient Eurasian groups.

In our new study[6], we reconstructed the historical spread of these genetic variants. We also estimated the temporal and geographical origins of the underlying selection pressures.

Further, we identified the gene in each hard sweep region most likely to have been selected for. Knowing these genes helped us understand the ancient pressures that may have led to their selection.

Coping with cold

Our findings suggest early humans went through a period of extensive adaptation, lasting up to 30,000 years, before the big diaspora between 60,000 and 50,000 years ago. This period of adaptation was followed by rapid dispersal across Eurasia and as far as Australia.

We call this period the “Arabian standstill”. Genetic, archaeological and climatic evidence all suggest these ancient humans were most likely living in and around the Arabian Peninsula.

The genetic adaptations involved parts of the genome related to fat storage, nerve development, skin physiology, and tiny hair-like fibres in our airways called cilia. These adaptations share striking functional similarities with those found in humans and other mammals living in the Arctic today.

We also detected similar functional similarities with previously identified human adaptive genes derived from historical mixing events with Neanderthals and Denisovans. These distant relatives of humans are also thought to have adapted to cold Eurasian climates.

Overall, these changes seem likely to have been driven by adaptation to the cool and dry climates in and around prehistoric Arabia between 80,000 and 50,000 years ago. The changes would also have prepared the ancient humans for the cold Eurasian climates they would eventually encounter.

Old adaptations, modern diseases

Many of these adaptive genes have links to modern diseases, including obesity, diabetes, and cardiovascular disorders. The adaptations around the human expansion from Africa may have established genetic variations that, under modern conditions, are associated with common diseases.

Read more: We found traces of humanity's age-old arms race with coronaviruses written in our DNA[7]

As we have suggested in another study[8], genes that were adaptive in the past might contribute to modern human susceptibility to various diseases. Identifying the genetic targets of historical adaptation events could help the development of therapeutic approaches and preventive measures for contemporary populations.

Our findings contribute to a new but growing literature highlighting the importance of adaptation in shaping human history. They also show the growing potential of evolutionary genetics for medical research.

References

  1. ^ published (www.pnas.org)
  2. ^ Previous research (www.nature.com)
  3. ^ evidence of past events (theconversation.com)
  4. ^ Ancient DNA reveals a hidden history of human adaptation (theconversation.com)
  5. ^ earlier work (www.nature.com)
  6. ^ new study (www.pnas.org)
  7. ^ We found traces of humanity's age-old arms race with coronaviruses written in our DNA (theconversation.com)
  8. ^ another study (theconversation.com)

Read more https://theconversation.com/ancient-humans-may-have-paused-in-arabia-for-30-000-years-on-their-way-out-of-africa-206200

Times Magazine

Building a Strong Online Presence with Katoomba Web Design

Katoomba web design is more than just creating a website that looks good—it’s about building an online presence that reflects your brand, engages your audience, and drives results. For local businesses in the Blue Mountains, a well-designed website a...

September Sunset Polo

International Polo Tour To Bridge Historic Sport, Life-Changing Philanthropy, and Breath-Taking Beauty On Saturday, September 6th, history will be made as the International Polo Tour (IPT), a sports leader headquartered here in South Florida...

5 Ways Microsoft Fabric Simplifies Your Data Analytics Workflow

In today's data-driven world, businesses are constantly seeking ways to streamline their data analytics processes. The sheer volume and complexity of data can be overwhelming, often leading to bottlenecks and inefficiencies. Enter the innovative da...

7 Questions to Ask Before You Sign IT Support Companies in Sydney

Choosing an IT partner can feel like buying an insurance policy you hope you never need. The right choice keeps your team productive, your data safe, and your budget predictable. The wrong choice shows up as slow tickets, surprise bills, and risky sh...

Choosing the Right Legal Aid Lawyer in Sutherland Shire: Key Considerations

Legal aid services play an essential role in ensuring access to justice for all. For people in the Sutherland Shire who may not have the financial means to pay for private legal assistance, legal aid ensures that everyone has access to representa...

Watercolor vs. Oil vs. Digital: Which Medium Fits Your Pet's Personality?

When it comes to immortalizing your pet’s unique personality in art, choosing the right medium is essential. Each artistic medium, whether watercolor, oil, or digital, has distinct qualities that can bring out the spirit of your furry friend in dif...

The Times Features

How much money do you need to be happy? Here’s what the research says

Over the next decade, Elon Musk could become the world’s first trillionaire[1]. The Tesla board recently proposed a US$1 trillion (A$1.5 trillion) compensation plan, if Musk ca...

NSW has a new fashion sector strategy – but a sustainable industry needs a federally legislated response

The New South Wales government recently announced the launch of the NSW Fashion Sector Strategy, 2025–28[1]. The strategy, developed in partnership with the Australian Fashion ...

From Garden to Gift: Why Roses Make the Perfect Present

Think back to the last time you gave or received flowers. Chances are, roses were part of the bunch, or maybe they were the whole bunch.   Roses tend to leave an impression. Even ...

Do I have insomnia? 5 reasons why you might not

Even a single night of sleep trouble can feel distressing and lonely. You toss and turn, stare at the ceiling, and wonder how you’ll cope tomorrow. No wonder many people star...

Wedding Photography Trends You Need to Know (Before You Regret Your Album)

Your wedding album should be a timeless keepsake, not something you cringe at years later. Trends may come and go, but choosing the right wedding photography approach ensures your ...

Can you say no to your doctor using an AI scribe?

Doctors’ offices were once private. But increasingly, artificial intelligence (AI) scribes (also known as digital scribes) are listening in. These tools can record and trans...