Articles: Funeral Practices among Neanderthals

Increasingly our ancestor/cousin species, the Neanderthals, seem a lot like...us.  Read this article about growing evidence the Neanderthals buried their dead.

Article: Neanderthal Genome Shows Signs of Inbreeding

This article discusses a secondary finding from a new genetic research:  the genome of a Neanderthal woman shows signs of inbreeding.

Article and Chart: Interbreeding Among Hominid Species

This chart summarizes nicely the emerging complexity of interbreeding among hominids.

Article: A Touch from the Ancients

This story describes an Austrian stone axe with the imprint of an ancient Homo erectus.  There is something about finding a fingerprint or hand imprint that makes archaeology suddenly so personal to me.

Article: Ancient Cave Paintings Found in Brazil

This article discusses the recent discovery of ancient -possibly 10,000 year old- cave paintings in Brazil.

Timeline

c. 448,000 BCE:  A glacier-fed ice lake catastrophically breaks through the chalk hills connecting what are today England and France.  In possibly less than a month this flood carves a canyon that will eventually become the English Channel.  The ice dam-ice lake-flood repeats through several ice ages with the canyon at times funneling a joint Thames-Rhine river system to the Atlantic.

c. 100,000 BCE:  At least three major river systems appear to have flowed north across the Sahara in this period.  The resulting corridors would have provided ways for early humans to cross the Sahara from sub-Saharan Africa to the North African coast.

c. 8500 BCE:  Cattle domesticated in the Near East.

c. 8000 BCE:  Cattle management is taking place in northern China.

c. 7500 BCE to 6400 BCE:  Hasan Dağ volcano had a minor eruption.  An artist appears to have recorded the eruption on a wall mural at Çatalhöyük, the earliest city/proto-city known.

c. 5500 BCE:  James Ballard finds human-made structures, fresh water shells, and drowned beaches under the Black Sea at a depth of 100m.  Carbon dating finds the shells are approximately 7500 years old.  Whether in a catastrophic flood or through gradual intrusion of Aegean salt waters into this former fresh water lake, the Black Sea floods.  Some argue this drove survivors into Europe as the first Neolithic farmers, but farming already had spread to modern Hungary.  The flooded area, however, represents a possible origin area for Indo-European speakers who may have begun their moves after flooding of their homeland.

1250 BCE to 1100 BCE:  300 year drought began in eastern Mediterranean.  Researchers believe this drought led to the collapse and/or decline of Bronze Age civilizations around the eastern Mediterranean and created the diaspora of Sea Peoples from Greece and other areas into the Levant and Egypt.

Article: Contradictory Studies on Cattle Origins

A new study finds genetic and other evidence for cattle domestication and management in northern China.  This new study points to the possibility that cows were domesticated about the same time in different parts of the world.  This would seem to contradict an earlier study linking cattle to a small herd domesticated in the Near East.

Article: African Slavery and American Genealogy

This article is a fascinating look at how genetics is assisting African-Americans in uncovering family genealogies.  In this case, a man was able to track down an ancestor captured and sold by a neighboring African kingdom into slavery.

Article: Earliest Representation of a Volcanic Eruption?

Earliest Representation of a Volcanic Eruption?

Catalhoyuk is a fascinating place. It is the earliest known example of a city -or proto-city.  Its homes were built adjoining each other with no streets.  Instead residents walked across the city's roofs and used ladders to climb down into their homes.  The city's dead were also buried in the floors of the homes.  Yet, this grand experiment seems to have been one of a kind with no other cities like it built around the area.

This article discusses a mural at the site that appears to be the earliest representation of a volcanic eruption of a nearby volcano.

Article: Pigs and the Sea Peoples

Pigs and the Sea Peoples

This article ties into other recent research into a series of severe droughts in the eastern Mediterranean around 1250 to 1100 BCE.  Researchers now theorize that the droughts created widespread famine and the collapse of Bronze Age civilizations around the eastern Mediterranean including the Mycenaeans, Hittites, etc.  Egyptian records speak of an invasion of Sea Peoples who appear to be displaced survivors seeking food and new homes.  The article on the genetics of Israeli pigs and wild boars appears to show an influx around the time of the Sea Peoples of European pigs.  Before this period the bones of pigs from the region show kinship with other, Near Eastern pig breeds.  So it appears the Sea Peoples brought their pigs with them, destroyed some of the Canaanite cities along the coast, and settled there.  Others have pointed to similarities between Cretan and Mycenaean pottery and the early pottery of the Philistines.

Article: Ancient European Admixture in the Americas, or Ancient Amerindian Admixture in Europe?

Ancient European admixture in the Americas, or ancient Amerindian admixture in Europe?

As I understand this article, mastodon hunters once occupied an environmental niche of steppes running from Europe to Siberia.  One group of hunters from Europe/West Asia migrated eastward to Siberia where a boy from this group was born and died.  It is primarily his DNA that is studied in the article.

The authors theorize this boy's relatives later interbred with humans whose genes are more common among East Asians.  This later, hybrid group of people -part European/West Asian and part East Asian genetically- later crossed Beringia to settle the Americas.

Article: Scientists Can Tell Your Ethnicity From The Germs In Your Mouth

Scientists Can Tell Your Ethnicity From The Germs In Your Mouth

Interesting article

Europe's First Farmers

Here is another post I wrote a few months ago for some friends:

Europe's First Farmers:  New genetic clues are developing a major historical mystery in Europe:

In geography there is the concept of diffusion or how things (ideas, peoples, diseases, fashions) spread across space to new lands.  In general, there are two ways new ideas -like say agriculture- would have spread from agriculture's birthplace in the Near East to Europe.  The 1) idea and technology of farming could have spread to Europe from one people to another or 2) farmers could have moved to Europe with their technology and families.  So did the idea of farming or the actual farmers move?

Some background:  Prior genetic and archaeological evidence points to the settlement of Europe by Neanderthals and then Homo sapiens.  The first Homo sapien populations were hunter-gatherers who were pushed back to refuges on the Iberian, Italian and Balkan peninsulas during the last Ice Age.  Homo sapiens arrived in Europe (Greece specifically) around 36,000 years ago.  About 9,500 BCE the first farming began in the Levant (Israel/Lebanon/Syria/Turkey) and spread to the Fertile Crescent and Turkey.  By about 7,000 BCE farming appears in Greece and spreads up the Danube Valley into Europe.

Adding to some earlier studies, a paper out last year in 2012 analyzed the DNA of 3 Neolithic hunter-gathers and 1 Neolithic farmer whose bodies were discovered in Sweden.  The genetic evidence suggests the farmer's DNA was much different than the hunter-gatherers' DNA.  The farmer's DNA in fact resembled that of ancient bodies found among Near Eastern immigrant farmers in Southern Europe.  Even Özti, the Austrian Ice Man, more closely resembles modern Sardinians genetically than modern Austrians.

So, it appears that the Neolithic farmers moved and took their farming technology with them into Europe.  These farmers, however, do not appear to have been as successful in passing on their genes though.  Today's Swedes more closely resemble the hunter-gatherers genetically than the early farmers.

Moreover, another recent paper looks at various Neolithic and Mesolithic ancient skeletons for their DNA.  It finds the earliest European farmers were immigrants from the Near East who settled and thrived from about 7000 to 2500 BCE.  Then there was a major population change with the DNA of these earlier settlers being replaced by new settlers who appear to have been from the Beaker-Bell population that spread along trade routes out of Portugal and Spain.  This group appears to have spread Celtic languages and to have been the main megalithic builders of sites such as Carnac and Stonehenge.  The genetic studies find their DNA relatively quickly becomes the dominant genomes in Europe; they largely replaced the former farmers.

Another study in Science argues the migration of the Corded Ware people from the Ukraine brought Proto-Indo-European into Europe.  If so, their influence must have quickly converted the original language of the Beaker-Bell ancestors to Celtic languages -a branch of Indo-European.  Or, the Bell-Beaker people are themselves an Indo-European offshoot.

So, the first wave of Homo sapien hunter-gatherers were largely crowded out by farmers from the Near East.  This second wave of farmers were then replaced by a culture of traders from Spain/Portugal with later additions from eastern Europe.  It is this third wave that defines the genetics of most modern Europeans and not the hunter-gatherers or the first farmers.

Article: Giving Voice to Proto-Indo-European

Reconstructing Proto-Indo-European

This is an interesting article on how linguistists are now working to reconstruct Proto-Indo-European not just as written words but actually spoken language.

Genetic Hybrids: Tales of 3 Lost Peoples Who Were Our Ancestors

This post is something I wrote for some friends:

As most of you know, one of my hobbies is my own take on genealogy:  the growing body of literature coming out of genetics studies that tell us about human prehistory.  There lately have been a bunch of new studies that I thought I'd put together for your reading pleasure:

Genetic Hybrids:  Tales of 3 Lost Peoples Who Were Our Ancestors:  New genetic evidence suggests that we modern humans are a hybrid species of sorts.  Most of our genome derives from our Homo sapien ancestors who evolved in Africa.  When the first modern humans left Africa, they encountered two other hominid species:  Neanderthals in western Asia and Europe; and Denisovans in Asia.  The discovery of the Denisovans was only announced in a 2010 paper after geneticists were stunned to find a finger bone and a few teeth -thought to be Neanderthal fossils- actually were a completely different yet related species.  Denisovans are named for the Denisova Cave in which these fossils were discovered.  This cave is in the Altai Mountains in Siberia.

Genetic evidence points to some interbreeding of Homo sapiens with Neanderthals and Denisovans.  2-6% of the DNA of non-Africans today appear to come from Neanderthals.  Indigenous sub-Saharan Africans usually do not show any Neanderthal DNA in their genomes.  It appears Homo sapiens' immune systems benefited from genes from our Neanderthal ancestors.   

One part of the diaspora out of Africa likely spread along the shores of the Indian Ocean from Africa to Arabia -> India -> Indonesia/Melanesia and finally Australia.  This group appears to have encountered the Denisovans because Melanesians have the highest percentage of Denisovan DNA in their genome (up to 6%).  Later settlers into Asia do not show much Denisovan ancestry. So the Denisovans either blended into a larger Homo sapiens population or died out before the next waves of Africans moved into Asia.  A 2013 study now suggests that Homo sapiens encountered the Denisovans not in Asia but in New Guinea or Australia after both groups successfully navigated the Indonesian sea barrier called Wallace's Line.

Finally, last year some geneticists published the results of a study of the DNA of various sub-Saharan African hunter-gatherer populations.  In their analysis they found evidence of an unknown third ancestral hominid who appears to have interbred with Homo sapiens.  Just as most Africans do not have Neanderthal or Denisovan ancestry, this mysterious third hominid species' DNA has so far only been found among these hunter-gatherer peoples in Africa. 

There are no fossil records for this 3rd species.  It doesn't even have a name yet.  One Stanford geneticist argues that the DNA doesn't point to a lost 3rd hominid people but reflects the DNA of our earliest Homo sapien ancestors.  For most African and all non-African humans, mutations have obliterated this original DNA.  So figuring out the answer to this is ongoing.

For Christmas I had my full genome analyzed (some people buy guns or handbags...I buy genetic tests...go figure).  My results came back last week and apparently my genome is 1.6% Neanderthal and an additional 1.6% Denisovan.  I was tickled to have a little bit of the rare Denisovan in me but a bit sad I wasn't more Neanderthal. :(

Some Factoids About Sunflowers

1. A recent genetic study -which I forgot to save- points to the sunflower being domesticated in a river environment in eastern North America.  The probable location is what is today Arkansas.  The new study points to a single site of domestication.  The alternative theories have the sunflower being domesticated in Mexico and spreading north or being domesticated twice:  once in Mexico and once in the eastern US. 

Arkansas' state flower though is the apple blossom. Maybe Arkansas should switch to its homegrown glory, the sunflower!

2. Sunflowers have been shown to absorb radioactive cesium from the soil.  They were planted around Chernobyl and now 10,000s are being planted around Fukashima, Japan.

Article: Dmanisi Skull May Point to Diversity within a Single Species

Unique Skull Find Rebuts Theories On Species Diversity in Early Humans

While not a genetic study, the Lordkipanidze article has an interesting angle to study of the most complete ancient skull of its age, the Dmanisi skull.  The researchers point out that there is considerable diversity to shape to the various skulls found in the cave.  Some have interpreted this as evidence of different hominid species living in the same cave over time, but the researchers in this article find that the Dmanisi skulls have no greater variability than comparing the skulls of a sample of humans living today.

D. Lordkipanidze, M. S. Ponce de Leon, A. Margvelashvili, Y. Rak, G. P. Rightmire, A. Vekua, C. P. E. Zollikofer. A Complete Skull from Dmanisi, Georgia, and the Evolutionary Biology of Early Homo. Science, 2013; 342 (6156): 326 DOI: 10.1126/science.1238484 

A. Margvelashvili, C. P. E. Zollikofer, D. Lordkipanidze, T. Peltomaki, M. S. Ponce de Leon. Tooth wear and dentoalveolar remodeling are key factors of morphological variation in the Dmanisi mandibles. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1316052110

Article: The Teeth Say the LCA of Modern Humans and Neanderthals Is Farther in the Past

Dental Study Takes Last Common Ancestor of Neanderthals and Homo Sapiens Back to 1 Million Years Ago

No Known Hominin Is Common Ancestor of Neanderthals and Modern Humans, Study Suggests

This study focuses on comparison of hominid teeth rather than genetics.  It argues the last common ancestor of Neanderthals and Homo sapiens lived at a much earlier date than currently postulated -closer to one million years ago.

Aida Gómez-Robles, José María Bermúdez de Castro, Juan-Luis Arsuaga, Eudald Carbonell, and P. David Polly. No known hominin species matches the expected dental morphology of the last common ancestor of Neanderthals and modern humans. PNAS, October 21, 2013 DOI: 10.1073/pnas.1302653110

Article: Using Herpes to Track Human Migrations

Hitchhiking Virus Confirms Saga of Ancient Human Migration

Aaron W. Kolb, Cécile Ané, Curtis R. Brandt. Using HSV-1 Genome Phylogenetics to Track Past Human Migrations. PLoS ONE, 2013; 8 (10): e76267 DOI: 10.1371/journal.pone.0076267

Article and Discussion: Four Key Migratory Events Shape the European Gene Pool

As you all know, I am intrigued by the stories genetics is adding to human history.  The journal Science has a very interesting article that I will summarize and contextualize for folks.

By about 600,000 years ago, the hominid ancestor of Neanderthals leaves Africa and eventually settles Europe.  This ancient relative of modern humans will evolve into Neanderthals.

~40,000 years ago:  The first modern humans, Cro-Magnons, enter Europe -probably via Greece and the Danube Valley.  They encounter Neanderthals, and genetics point to some limited interbreeding.

~30,000 to ~25,000 years ago:  The last full Neanderthals die out.  The last skeleton of Neanderthals found to date is from a cave in Gibraltar.  

~28,000 to ~14,000 years ago:  The last Ice Age drives human and Neanderthal populations south to four refuges in a) Iberia, b) Italy, c) the Balkans, and d) the Ukraine.  A mutation arises in the population living in Iberia.  This mutation gives rise to the Rhesus negative factor in human blood (A-, B-, O-, and AB-).  Today  about 50% of Basque people carry this mutation with the frequency of the mutation dwindling the farther you get from the Pyrenees.  

~8,000 years ago:  agriculture arrives in Europe -again with people moving up the Danube Valley- via farmers immigrating from Turkey (Anatolia) and the Fertile Crescent.  These first European farmers appear genetically to be similar to modern Sardinians, residents of a large, relatively isolated island that is now part of Italy.  The genetics of Ötzi, the Ice Man whose body was found in a glacier on the Austrian-Italian border, places him as belonging to this group of Neolithic farmers.  The T and J mitochondrial haplogroups are also associated with these first farmers.  Note:  Ötzi and I are both in the T haplogroup.

~7,500 years ago:  Among the new Neolithic farmers in the Danube Valley a mutation occurs that will allow most Europeans to have lactose persistence, or the ability to digest dairy products after childhood.  

Now for where the paper starts off:

Geneticists and historians wondered if the first farmers assimilated the original Cro-Magnon hunter-gatherers, killed them off, or diluted their genetic contributions by filling Europe with larger families supported by agriculture. Instead, the researchers -Brandt et al.-  found some really unexpected and fascinating things by comparing modern European populations' DNA with the DNA from skeletons found in central Germany.  These German skeletons cover 4,000 years of history from the first farmers to about 3,500 years ago during the Bronze Age.  What did they find?

a. For 2,000 years after the Neolithic farmers arrived, there appears to have been limited interbreeding between the farmers and the hunter-gatherers.  The farmers appear to have been successful with their numbers steadily growing.  It is interesting to ponder what social mechanisms kept two populations from intermarrying for two millennia.  

b. ~7000 years ago:  About a 1,000 years after the farmers arrived, their overall percentage in the gene pool appears to decline and the hunter-gatherers and their genes make a comeback.  This may have resulted from climate change or disease.  Adapting Near Eastern plants and farming to cooler Europe surely must have entailed crop failures and setbacks.  The rapid spread of the lactose persistence gene points to the importance of dairy.  The ability to digest it conferred survival when those without it starved.  Moreover, most infectious diseases in humans arise from pathogens that jump the species boundary and are more likely to infect people living with livestock.  

c. ~4,800 years ago:  A new migration of people from the Russian steppes arrives.  These people have horses and carts.  They decorate their pottery in a distinctive design giving them the name the Corded Ware people.  They likely are the first proto-Indo-European speakers, and thus are the linguistic ancestors of almost every European language spoken today except Basque, Hungarian and Finnish.

d. ~4,500 years ago:  A fourth migration starts in Portugal around modern Lisbon.  These people, the Bell-Beaker people, work copper and appear to have a culture built around trade.  They make pottery in the shape of wide-lipped, upside-down bells and build megalithic stone monuments.  At first they spread along the Atlantic and Mediterranean coasts.  These first maritime settlements include modern Brittany in northwest France.  From there the traders appear to follow existing, ancient trading routes up the valley of the Seine to the Rhine and then into the heart of Germany.  In Germany the Bell-Beaker traders mix with the a) hunter-gatherers, b) farmers, and c) Indo-European speakers.  They bring with them the H mtDNA haplogroup, the most common maternal lineage in Europe today.

The authors say Europeans' -and European-Americans'- DNA is a more complex story than Neolithic farmers simply replacing Paleolithic hunter-gatherers.  Instead, today's European gene pool appears to be a mix of these four migrations plus a little Neanderthal, Denisovan, and some later additions from outside Europe.

Guido Brandt, Wolfgang Haak, Christina J. Adler, Christina Roth, Anna Szécsényi-Nagy, Sarah Karimnia, Sabine Möller-Rieker, Harald Meller, Robert Ganslmeier, Susanne Friederich, Veit Dresely, Nicole Nicklisch, Joseph K. Pickrell, Frank Sirocko, David Reich, Alan Cooper, Kurt W. Alt, the Genographic Consortium. Ancient DNA Reveals Key Stages in the Formation of Central European Mitochondrial Genetic Diversity. Science, 2013 DOI: 10.1126/science.1241844

Article: Was There a Paleolithic Population Boom?

Genetic Study Pushes Back Timeline for First Significant Human Population Expansion

This article discusses some recent genetic research that argues the Homo sapien population expanded rapidly during the Paleolithic 60,000-80,000 years ago.  In those areas that saw the most expansion, a second Neolithic expansion occurred more robustly about 10,000 years ago with the invention of agriculture.

Article: Denisovans East of Wallace's Line?

Did Homo sapiens encounter the mysterious Denisovans east of Wallace's Line?

Mysterious Ancient Human Crossed Wallace's Line

Wallace's Line represents a water boundary separating the southeast Asian part of Indonesia from the western part of the Indonesian archipelago, New Guinea, and Australia.  The above Science Daily article summarizes the work of Cooper and Stringer who argue that early modern humans -Homo sapiens- met and interbred with Denisovans, a related hominid species, east of Wallace's Line.  Having the interbreeding take place in this area would help explain why Denisovan DNA is found in the highest concentrations among the aboriginal peoples of New Guinea and Australia, but it would also mean the Denisovans also managed to cross the watery Wallace's Line and thus likely had boats.

One intriguing remark in this article is the statement that it appears Denisovan males mated with Homo sapien females.  Were there no Homo sapien males mating with Denisovan females?  

A. Cooper, C. B. Stringer. Did the Denisovans Cross Wallace's Line? Science, 2013; 342 (6156): 321 DOI:10.1126/science.1244869

Welcome!

Welcome to my blog on human genetics and prehistory.  I use this blog as a way to collect and share my interest in how genetics is opening a doorway into human migrations and geography.