We Are Not Who We Thought We Were

In a recent blog I playfully flipped the manner in which we thought of ourselves (Homo sapiens) and Neanderthals. We have known for a couple of decades that people with Eurasian heritage contain around 2-4% Neanderthal DNA in their make-up. Humans living in China, SE Asia, Melanesia, and Australia have around 4-6% Denisovan DNA.

My light-hearted jest was to claim that we are actually Neanderthals with around 96-98% Homo sapiens DNA.

Since then I have discovered research that indicates that my flippancy is much more accurate than I first thought.

So much has occurred within anthropology, archaeology, and genome research since 2010. Most of us non-professionals and laypeople have not been able to keep up, or even understand that such momentous findings have taken place.

Kicking off these findings, in 2010, was the discovery of a previously unknown member of the Homo genus – the Denisovans. It wasn’t a remarkable finding either, at least not to those of us who are laypeople. It was “merely” a juvenile finger bone. Within that bone however, mitochondrial DNA indicated that this was a “new” human. Named after the cave in which the finger bone was found – Denisova Cave – the Denisovans (a.k.a. Homo longi) are closely related to the Neanderthals and surmised to have lived throughout Asia between 200,000 – 32,000 years ago.

Until 2019 this finger bone was the only fossil that informed our knowledge of the species. Although found in 1980 in a cave on the Tibetan Plateau a mandible was classified as also belonging to a Denisovan. Since then, further Denisovan fossils have been found in Laos, the Taiwan Trench, and China, including an almost complete skull in Harbin, China.

Another piece of the jigsaw that makes up modern humans (Homo sapiens), Denisovans, and Neanderthals also came in 2010. The complete Neanderthal genome sequence was published that year by a team of almost sixty researchers from Germany, USA, China, UK, Spain, Croatia, Russia, and Ireland.¹ This paper deduced that ‘…the proportion of Neanderthal ancestry of non-Africans (was estimated) to be between 1% and 4%.’ At the time this paper was published, Denisovan DNA had not been sequenced, hence the estimate assumed Neanderthal DNA to be present in all populations outside sub-Saharan Africa.

Then, in 2014, two studies indicated that 20% or more Neanderthal DNA was distributed throughout the whole modern human genome. Thus, although you (if you are of Eurasian descent) may have only one or two percent Neanderthal DNA, when the entire human population is considered, one-fifth of the DNA comes from our Neanderthal cousins.

Two years later an even more staggering research finding was released. Nathan Schaefer and his team at Santa Cruz University concluded that, ‘…only 1.5 to 7% of the modern human genome is uniquely human.’²

Let me repeat that: ‘…only 1.5 to 7% of the modern human genome is uniquely human.’

Our modern human genome is made up of “recycled parts” as the paleoanthropologist, evolutionary biologist, and TV presenter, Ella Al-Shamahi, dubs it in a documentary presented by New Scientist.

Our modern DNA has been arrived via what geneticists call introgression (the transfer of genetic material from one species into the genetic pool of another) at a time when Homo sapiens shared the planet with other species of the Homo genus. During the Middle Palaeolithic and early Upper Palaeolithic Homo sapiens emerging from Africa encountered, and interbred with, Homo neanderthalensis in Eurasia and Denisovans in Asia, SE Asia, Oceania, and into the Americas. Back-migration from Eurasia into northern Africa introduced Neanderthal DNA to humans living there. Low levels of Neanderthal DNA have also been found in sub-Saharan Africa.

The story does not end there, however.

Earlier this year (in July 2026) researchers from the University of California, Berkely, revealed that the genome of modern humans included DNA from two “ghost ancestors.”³ One of these ancestors interbred with Homo sapiens more than 50,000 years ago, before the latest out-of-Africa migration. This “archaic” lineage is, according to researchers, present in all modern-day humans.

The second “ghost ancestor” is even older. Researchers refer to a “super-archaic ancestor” interbreeding with Denisovans more than 200,000 years ago. As we know, Denisovans later interbred with Homo sapiens and so the DNA of this super-archaic ancestor resides in modern humans.

We are definitely not who we thought we were.

We are definitely not unique.

Implications

All of this is undoubtedly of enormous interest to palaeontologists, archaeologists, anthropologists, and evolutionary biologists, and possibly of curiosity value to laypeople (such as the present writer).

It also has implications for how we perceive ourselves.

For a large part of our recorded history we have viewed ourselves as being either a) at the top of a divinely ordered creation or, b) the pinnacle of the evolutionary tree of life. In each case we have held onto the myth of human exceptionalism.

These findings undermine that myth.

These findings suggest a more humble understanding of our role in nature.

These findings hint that we should not take ourselves too seriously.

We are not at the top of anything. We are not the pinnacle.

We are “recycled parts” from a number of different species, including some that are still ghostlike.

Notes:

1. https://pmc.ncbi.nlm.nih.gov/articles/PMC5100745/  accessed 28 October 2026

2. https://www.science.org/doi/full/10.1126/sciadv.abc0776  accessed 28 October 2026

3. https://www.sciencedaily.com/releases/2026/07/260731034139.htm  accessed 28 October 2026