Where Did We Come From? is the title of a book written by Carl Zimmer in the wake of the discovery of the “hobbits” of Flores fifteen years ago. It was a very good popular introduction to human evolution.
According to Zimmer, our African ancestors parted company with the ancestors of chimpanzees and bonobos six or seven million years ago to begin developing an upright posture, tool use and, perhaps most importantly, language. Our own species, Homo sapiens, evolved about 200,000 years ago and began spreading out of Africa 130,000 years ago, through Europe, Asia, Australia and, eventually, America. We lived alongside closely related species until comparatively recent times. Neanderthals reached Europe before we did and coexisted with us there until 28,000 years ago, if not later. The ‘hobbits’ of Flores, by far the most spectacular recent discovery in the field, survived as recently as 18,000 years ago, well after Homo sapiens had migrated through South Asia and the islands to Australia.
Given the pace of discovery in the field, Zimmer’s book is now somewhat out of date. This collection of recent articles introduces research which adds depth and complexity to Zimmer’s account without changing its broad outlines. I have assembled them here in evolutionary order. Each story is represented by its headline and an excerpt, followed by a link to the source. People in Australia before Europeans arrived (Jan 2021 plus updates) continues the Australian part of the story up to the era of European colonisation.
Millions of years ago
Ancient fossil skull discovered in Ethiopia fills critical gap in human evolution
• A rare 3.8 million year-old skull found in Ethiopia is rewriting our understanding of the human family tree
• Previously, only fragments had been found of Australopithecus anamensis, the oldest-known member of a group that gave rise to the species made famous by the Lucy skeleton
• Analysis of the skull shows A. anamensis had a mix of features from primitive species as well as Lucy
Paranthropus butchering hippos
Fossils of Paranthropus discovered with stone tools they seem to have made and remains of hippo they seem to have butchered, all 2.9 million years ago in Kenya. theconversation.com/we-found-2-9-million-year-old-stone-tools-used-to-butcher-ancient-hippos-but-likely-not-by-our-ancestors-199499
Earliest known skull of Homo erectus unearthed in South Africa
The earliest known skull of Homo erectus has been unearthed by an Australian-led team of researchers who have dated the fossil at two million years old …
The lead researcher Prof Andy Herries said the skull was pieced together from more than 150 fragments uncovered at the Drimolen Main Quarry, located about 40km north of Johannesburg in South Africa.
Tool-making in Morocco
Archaeologists in Morocco have announced the discovery of North Africa’s oldest hand axe manufacturing site, dating back 1.3 million years. The Stone Age find pushes back the start date of the Acheulian stone tool industry — associated with human ancestor Homo erectus — by hundreds of thousands of years.
It was made during excavations at a quarry on the outskirts of Casablanca.
…the beginning of the Acheulian in Morocco was now close to the South and East African start dates of 1.6 million and 1.8 million years ago respectively. Before the find, Morocco’s Acheulian stone tool industry was thought to date back 700,000 years. …
Mr Mohib said the study also made it possible to attest to “the oldest presence in Morocco of humans” who were “variants of Homo erectus”.
Ancestors of Flores ‘hobbits’ may have been pioneers of first ‘human’ migration out of Africa
The Flores hominins were, more clearly than ever, rooted deep in that [family] tree: they could not be descendants of Homo erectus. They came from something more primitive – a close cousin of Homo habilis. But what was an ancient-looking hominin like this doing in Indonesia?
In the most widely accepted model of human evolution today, the first emergence of hominins out of Africa involved Homo erectus, and happened some time after 2m years ago. But Homo floresiensis raises the tantalising possibility of an earlier expansion of hominins – who were probably not-quite-Homo – out of Africa.
More than 100,000 years ago
Hibernation in Europe
It seems that our ancestors may have hibernated to cope with the extreme European winters around 400 000 years ago. https://www.theguardian.com/science/2020/dec/20/early-humans-may-have-survived-the-harsh-winters-by-hibernating
Burials in Africa
Burials carried out by Homo naledi in a South African cave, 200,000 years ago, have recently been discovered. They push back the date of the earliest known burials by any Homo species, but more importantly signify that these distant relatives were more like ourselves than we thought possible. https://www.abc.net.au/news/2023-06-06/worlds-oldest-known-burial-site-found-in-s-africa/102444736
More about the Hobbits
The Australian Museum has lots more information about the hobbits at https://australianmuseum.net.au/learn/science/human-evolution/homo-floresiensis/ Here are a couple of key points:
The human remains date from about 100,000 to 60,000 years old, but archaeological evidence (mostly associated stone tools) suggests H. floresiensis lived at Liang Bua from at least 190,000 to 50,000 years ago (recent dates published in Nature, March 2016). These dates make it one of the latest-surviving humans along with Neanderthals, Denisovans and our own species H. sapiens.
Most scientists that accept H. floresiensis as a legitimate species now think its ancestor may have come from an early African dispersal by a primitive Homo species similar in appearance to H. habilis or the Dmanisi hominins. This means that it shared a common ancestor with Asian H. erectus but was not descended from it.
In 2016, scientists announced they had discovered the lower jaw and teeth from at least one adult and possibly two children of what may be an early form of H. floresiensis. These fossils were found at Mata Menge, about 70kms east of Liang Bua cave on Flores and date to 700,000 years old.
A Shocking Find in a Neanderthal Cave in France
A rock structure, built deep underground, is one of the earliest hominin constructions ever found. By measuring uranium levels on either side of the divide, the team could accurately tell when each stalagmite had been snapped off for construction.
Their date? 176,500 years ago, give or take a few millennia.
“When I announced the age to Jacques, he asked me to repeat it because it was so incredible,” says Verheyden. Outside Bruniquel Cave, the earliest, unambiguous human constructions are just 20,000 years old. Most of these are ruins—collapsed collections of mammoth bones and deer antlers. By comparison, the Bruniquel stalagmite rings are well-preserved and far more ancient.
This startling story quickly earned a response in Nature by Prof Chris Stringer, Research Leader in Human Origins at the Natural History Museum, London:
A comment on the ‘Early Neanderthal constructions deep in Bruniquel Cave in southwestern France’
The remarkable discovery of different-sized ‘structures’ made from purposefully broken stalagmites deep within Bruniquel Cave, south west France, would be significant for any period of time, but at around 175,000 years, these must have been made by early Neanderthals, the only known human inhabitants of Europe at this time.
The purpose of the structures and concentrated combustion zones which are mostly on the broken stalagmites rather than on the ground remain enigmatic, but they demonstrate that some Neanderthals, at least, were as much ‘at home’ deep within the cave as at its entrance.
There are examples of human habitation 30 or 40 metres into the dark zones of caves from sites of this or even greater age in Africa , but the Bruniquel occupation is some ten times deeper into the cave, and shows constructions as complex as some made by modern humans only 20 or 30,000 years ago.
Early humans in the Americas 130,000 years ago
High-tech dating of mastodon remains found in southern California has [pushed] the presence of hominins back to 130,000 years ago rather than just 15,000 years, researchers said Wednesday.
Teeth and bones of the elephant-like creature unmistakably modified by human hands, along with stone hammers and anvils, leave no doubt that some species of early human feasted on its carcass, they reported in the journal Nature. …
One possibility that can be excluded with high confidence is that they were like us. Homo sapiens, experts say, did not exit Africa until about 80,000 to 100,000 years ago.
But that still leaves a wide range of candidates, including several other hominin species that roamed Eurasia 130,000 years ago, the authors said.
They include Homo erectus, whose earliest traces date back nearly two million years; Neanderthals, who fought and co-mingled with modern humans across Europe before dying out some 40,000 years ago; and an enigmatic species called Denisovans…
phys.org/news/2017-04-humans-america-years-earlier-thought.html
Hominins moving out of Africa 120 000 years ago left footprints in Arabia –
phys.org/news/2020-09-ancient-footprints-saudi-arabia-humans.html
Tens of thousands of years ago
Homo sapiens in Laos
Remains of Homo sapiens in Northern Laos, dated back to 86,000 years ago. abc.net.au/news/science/2023-06-14/oldest-evidence-for-modern-humans-in-mainland-south-east-asia/102471990
Burial practices in Africa, 78,000 years ago
…and Europe even longer ago:
Scientists have uncovered the remains of a three-year-old human child who was buried 78,000 years ago in Kenya. The position of the bones and chemical analyses suggest the child was buried deliberately. While older burial sites have been found in Europe, this is the oldest that has been found in Africa to date.
…[Excavations] … in Europe [show] that Neanderthals and early modern humans had been formally burying their deceased loved ones near their homes for at least 120,000 years. And in the Es-Skhul and Qafzeh caves in Israel, researchers have found early modern human burials that date back to around 100,000 years.
abc.net.au/news/science/2021-05-06/oldest-human-burial-site-in-africa/100065050
Scientists find evidence of ‘ghost population’ of ancient humans
Scientists have found evidence for a mysterious “ghost population” of ancient humans that lived in Africa about half a million years ago and whose genes live on in people today.
Traces of the unknown ancestor emerged when researchers analysed genomes from west African populations and found that up to a fifth of their DNA appeared to have come from the missing relatives.
Geneticists suspect that the ancestors of modern west Africans interbred with the yet-to-be-discovered archaic humans tens of thousands of years ago, much as ancient Europeans once mated with Neanderthals.
theguardian.com/science/2020/feb/12/scientists-find-evidence-of-ghost-population-of-ancient-humans
Neanderthal-Denisovan ancestors interbred with a distantly related hominin
Previous research has shown that modern Eurasians interbred with their Neanderthal and Denisovan predecessors. We show here that hundreds of thousands of years earlier, the ancestors of Neanderthals and Denisovans interbred with their own Eurasian predecessors—members of a “superarchaic” population that separated from other humans about 2 million years ago. The superarchaic population was large, with an effective size between 20 and 50 thousand individuals. We confirm previous findings that (i) Denisovans also interbred with superarchaics, (ii) Neanderthals and Denisovans separated early in the middle Pleistocene, (iii) their ancestors endured a bottleneck of population size, and (iv) the Neanderthal population was large at first but then declined in size. We provide qualified support for the view that (v) Neanderthals interbred with the ancestors of modern humans.
That’s the “Abstract” (the authors’ summary) of a scientific paper which is rather similar to the one on which the previous story is based. The whole paper can be found at advances.sciencemag.org/content/6/8/eaay5483
This is what mysterious ancient humans might have looked like
We know that mysterious ancient humans called Denisovans once lived alongside Neanderthals, thanks to a few bones and teeth recovered from a cave in Siberia. Now, for the first time, researchers have shared what they might have looked like. … the reconstruction is that of a young female Denisovan.
https://edition.cnn.com/2019/09/19/world/denisovan-first-look-scn/index.html
Family life among Neanderthals 54,000 years ago
- DNA extracted from Neanderthal remains found in a Siberian cave revealed a close-knit community of 10 to 20 individuals
- Genetic analysis also suggests that females moved between groups, while males tended to stay in their clan
45 000 year old cave paintings in Sulawesi
…which are now threatened by climate change: abc.net.au/news/2021-06-10/sulawesi-cave-paintings-climate-hange-achaeologists-sale-erosion/100206280
Major surgery 31,000 years ago
A young adult unearthed in a Borneo cave is the earliest-known case of a successful major limb amputation. A skeleton unearthed in a Borneo cave was missing the lower part of their left leg and the bones, dated to around 31,000 years old, showed signs of deliberate surgical amputation. Growths on the bones’ cut end suggest the person not only survived, but lived for at least six years after the amputation.
The bones were found in a vast, airy limestone cave called Liang Tebo in eastern Kalimantan.
abc.net.au/news/science/2022-09-08/earliest-amputation-foot-leg-skeleton-borneo-cave-archaeology/101406744
Looking for context
Wikipedia has a beautifully organised and illustrated table of important hominid fossils from 7 million to 5000 years old, i.e., from the last common ancestor we share with chimpanzees, to Otzi the iceman, at en.wikipedia.org/wiki/List_of_human_evolution_fossils
In the light of the recent discoveries above, its key lessons seem to be (1) how few pieces of the puzzle we still have and (2) the extent of the overlap between different species of people from 300,000 to 40,000 years ago. Point (1) is, of course, the reason that a single discovery can radically change our understanding of our evolution.
Aside from the purely scientific aspects, our history raises fascinating questions about the borderlines between human animals and other animals – borderlines in consciousness and intelligence, and the ethical borderlines which guide our sense of our proper place in the environment.
A two million year old skull in South Africa, from a contemporary of Homo erectus. https://www.abc.net.au/news/2020-11-10/archaeologists-find-skull-of-human-cousin-two-million-years-old/12869110
https://www.abc.net.au/news/2021-07-29/morocco-1-3-million-year-old-stone-age-axe-discovery/100332946
https://www.nature.com/articles/s41467-018-04375-6
This site – https://news.asu.edu/content/researchers-discover-wealth-power-may-have-played-stronger-role-survival-fittest – has a different version of the same story.
It’s complicated but the basic idea is that, at a particular stage of social development, frequent conflicts between male-dominated groups led to the extinction of male lineages so that we have fewer male ancestors than female ancestors.
A burial in Sulawesi 7300 years ago suggests that there may have been an earlier wave of migration towards Australia that we didn’t suspect. https://www.abc.net.au/news/science/2021-08-26/skeleton-genome-dna-indigenous-australia-png-indonesia-sulawesi/100400618
Genetics of Polynesians reveals their exploration and settlement history, from Samoa (about 830 CE) to the Cook Islands, Easter Island and New Zealand by about 1250. https://www.abc.net.au/news/science/2021-09-23/polynesia-settlement-pacific-islands-genome-dna-rapa-nui-history/100471492
The Comments trail was becoming unwieldy so I have integrated many of the comments into the body of the post, in their chronologically correct places.
Also, People in Australia before the Europeans arrived, at https://malcolmtattersall.com.au/wp/2021/01/people-australia-before-europeans/, continues the theme of this post with a focus on Australian prehistory. There is some chronological overlap with this post, since the earliest Australian archaeological finds are at least 65,000 years old.
An anthropologist who worked in Indonesia for decades has collected evidence that the ‘hobbit’ may have survived into present times, and written a book about it. Here he talks about his work and his book. https://thedebrief.org/a-humanlike-living-fossil-could-still-be-alive-in-indonesia-this-anthropologist-says/
A ritual wooden sculpture from Siberia, preserved in a peat bog for 12,500 years.
https://www.smithsonianmag.com/smart-news/earliest-surviving-wood-sculpture-even-older-previously-thought-180977320/
Neanderthals and Denisovans lived in same Siberian cave for 100,000 years
Denisovans — an extinct species of human whose genome was reported in 2011 — occupied the cave from around 287,000 to 50,000 years ago. This overlapped with Neanderthals, who also resided there but for a shorter period: between around 193,000 and 91,000 years ago.
…the oldest and youngest Denisovan fossils were 194,400 years old and 51,600 years old respectively. The Neanderthals were between 90,900 and 147,300 years old and the Neanderthal/Denisovan child was between 79,300 and 118,100 years old…
https://www.abc.net.au/news/science/2019-01-31/denisovans-neanderthals-siberian-cave-hominin-human-archaeology/10751116
More on Neanderthals, a long read which is more philosophical than scientific but does summarise the science. https://www.theguardian.com/science/2023/sep/19/justice-for-neanderthals-what-the-debate-about-our-long-dead-cousins-reveals-about-us
It has long been known that people arrived in the Americs via Siberia, but the date of their arrival has been pushed back by recent work. 21 – 23 000 years go is the new date, and it’s from New Mexico so the real date is somewhat earlier still. https://www.abc.net.au/news/2023-10-06/evidence-footprints-new-mexico-oldest-sign-of-humans-americas/102943760
Evidence that indigenous Australians may be the only remaining (unmixed) descendants of the earliest wave of emigration of modern humans from Africa, which may have occurred as early at 130 000 years ago, while the ancestry of ‘Papuans, Melanesians, and possibly the Aeta ‘Negrito’ from the Philippines’ may be a mixture of that first wave of emigrants and a later one. https://www.sciencedirect.com/science/article/abs/pii/S0047248415001608?via%3Dihub
Evidence suggesting that a wave of emigrants from Africa 70 000 years ago paused for about 20 ooo years arounf modern Iran before expanding further to both east and west. https://www.abc.net.au/news/science/2024-03-26/out-of-africa-human-migration-persian-plateau/103614458
Another Sulawesi cave painting, this one dated to 51,000 years ago. https://www.aljazeera.com/news/2024/7/4/worlds-oldest-artwork-discovered-in-indonesian-cave