I really think it is time to come up with a better name for ancient people from sub-Saharan Africa than "humans". If all the different hybrid people alive today are humans, then it is very misleading to call one branch "human" and the others Neanderthal or Denosovan.
John Hawks has a good little post on this from just a few weeks ago [1]:
Anthropologists usually do call Neanderthals “humans”. Ironically, experts differ more from each other about how to define species (and Homo sapiens with it) than on how to define human.
Neanderthals did interbreed with the descendants of African early modern humans, and Neanderthals are among the ancestors of people living today. For many, that is enough to recognize that Neanderthals are Homo sapiens.
...
What the data do show is that the populations that existed at the time of Neanderthals (and Denisovans) were a lot more different from each other than anybody living now. That makes the current variation of humans, including the idea of race as we usually understand it, a bad model for what was happening at the time these populations lived, more than 50,000 years ago. So we are working to find new ways to talk about these kinds of populations that will be accurate, and not rely upon our understanding of people in the present.
His longer post[2] covers more of the rapidly shifting ground in the story of human origins, which is becoming a more fascinating story almost by the day.
But Neanderthal and Denisovan people are usually called humans, aren't they?
As far as I know, all Homo are humans. Homo sapiens is just one of the human species, the only one that is still extant, usually called "modern humans".
The only controversy I've heard on how to define humans is whether chimpanzees should be part of the Homo genus as well (making them humans, although a different species from us) or not.
I believe this is because the sub-Saharan African humans would be anatomically modern, while the others would not. Even though there was gene flow back into European and Asian humans from Neanderthals and/or Denisovans, it apparently doesn't count for much in their physiology compared to their sub-Saharan genetics.
But I don't think "human" excludes those groups, when not qualified. My understanding is that there's a continuum between the first archaic humans that diverged from chimpanzees and the behaviorally modern human. The anatomically modern human predates the behaviorally modern human. It coexisted and interbred with archaic humans, but is believed to be the predominant ancestor of all extant humans. (Although some argue that anatomically modern humans are indistinguishable from behaviorally modern humans.)
It's pretty wild to me to imagine that for all of our diversity and abundance today, there was much greater diversity of homonins at a time when we were much fewer in number.
> It's pretty wild to me to imagine that for all of our diversity and abundance today, there was much greater diversity of homonins at a time when we were much fewer in number.
Fewer in numbers means more isolation between groups.
In addition to that, early stages of culture may or may not have further augmented isolation. This is purely speculative of course, but we are in "imagine" territory anyways. Then the first group to develop cultural traits that somehow facilitated crossbreeding might have triggered a cascading melting pot effect, leading to the relatively uniform "modern human".
Neanderthalensis, like Sapien, is a species name. When we talk about these things in the context of evolutionary biology, those precise terms tend to work better than a more broad and abstract word like "Humans."
But, in articles like this, you see mixed jargons. One academic source may specialize in evolutionary biology and its particular jargon, and another source may specialize in anthropology. Their disparate perspectives and jargons are filtered through the lens of a journalist who specializes in neither field.
Each group assigns a different meaning to these words.
There is a precise and correct word in the academic context for each category of early hominids, but it probably isn't realistic to expect writers to use jargon from a field other than the one they specialize in.
They aren't. They are Homo sapiens, vs homo neanderthalis, homo erectus or the like. There used to be many closely related humans. But we eradicated them (in all likelihood).
From that perspective, sapiens would be a better term than humans..
We haven't eradicated them, we have bred with them. Most of us are the decendents of both the sub-Saharan people and Neanderthal people and some of us are the descendants of sub-Saharan people, Neanderthal people, and the Denosovan people (three different species). If we are all human now then why is only one ancient population from Africa called human.
We bred with them, but evolution has been heavily eliminating the traces of the breeding and they are generally often linked with diseases. So they do not seem to be on equal grounds. And as for 'us' - speak for yourself, but much of the human race has no Denisovan or Neanderthal ancestry.
A fifth of the entirety of humanity is a heck of a lot. If you want to claim that Denisovan or Neanderthal ancestry is just as crucial as the basal homo sapiens, you are writing off a good chunk of humanity. Combine this with the purging of Neanderthal DNA (and the likely purging of the little bit of Denisovan introgression), it's clear that one of these things is not like the others. Let's not overstate the implications of these things.
> ...but evolution has been heavily eliminating the traces of the breeding and they are generally often linked with diseases.
Do you have a citation for this? I was under the impression that greater genetic diversity usually leads to greater disease resistance, because disease-prone genes tend to be eliminated more quickly by natural selection.
Greater genetic diversity might seem like a good thing, but there's a lot of details. Neanderthals might have been too alien for their variants to be 'compatible' with humans (not as surprising as it might sound, an interesting paper from yesterday reports that this sort of incompatibility may be responsible for as many as 95% of one project's mouse strains dying out despite all of them being interbreedable: http://genestogenomes.org/behind-the-cover-male-infertility-... ), or they may have suffered from a higher mutation load due to their small population - small populations can't select as effectively against bad mutations, so will be genetically less healthy. (This also might be part of why human mutation load was shrinking over time up until a few thousand years ago, "The Genomic Health Of Ancient Hominins" http://biorxiv.org/content/early/2017/06/02/145193 Berens et al 2017, all the new variants being slowly sorted through.)
Thus, while some Neanderthal/Denisovan variants may have been helpful to humans (like the Tibetan altitude adaptations), overall they appear to have been harmful and are disappearing.
How's wot?
As far as I have been informed, [1] surviving Europeans/Asians are Neanderthalized (hybrids), and [2] no pure Neanderthals are living today.
I think you should read the rest of this conversation thread. Some population groups are surviving hybrids but the percentage is very small (my own Neanderthal percentage is just 2.4%, so I'm actually almost more Jewish than Neanderthal), not evenly distributed (Asian is much less AFAIK, it's mostly a European thing), and even in the ones which are, the percentage of hybridization is decreasing steeply over time; and yes, all the Neanderthals are gone, which doesn't speak well for their fitness.
> Some population groups are surviving hybrids but the percentage is very small
The pure genotypes were obviously out-competed, surviving Europeans and (East?) Asians are descendants of hybrids.
Aside 1:
> Asian is much less AFAIK, it's mostly a European thing)
Latest I heard is that it's actually the other way around, East Asians are more N. than Europeans.
Aside 2:
> my own Neanderthal percentage is just 2.4%, so I'm actually almost more Jewish than Neanderthal
So you've been told that you're mumble percent Jewish? Have you verified that you don't just happen to have a bunch of perfectly European genes that—even though characteristic for Ashkenazic Jews—are not at all unique to them because of their >60% European admixture?
> The pure genotypes were obviously out-competed, surviving Europeans and (East?) Asians are descendants of hybrids.
Non-Neanderthal-descended-humans obviously weren't out-competed since they still exist, and because of all the evidence for harm from the Neanderthal variants which is why the variants are being selected against.
> Have you verified that you don't just happen to have a bunch of perfectly European genes that
Pretty sure. I trust 23andMe to get ancestry right for white people like me. And further, the genealogists in the family already knew about there being one Jew in the family tree who converted to Catholicism & married into the family about the right number of generations back; I had had no idea because I don't care about that sort of thing.
I often see Neanderthals referred to as Homo sapiens neanderthalensis, so it's not quite as clear cut that they're a separate species. And indeed, by the definition of "a population that can interbreed and produce viable offspring", if many of us have Neanderthal genes then we would be the same species.
Questions being asked like "What is human?" or "What defines a species?" have differing answers depending on the specific world-view of the questioner.
As I have read the comments already given, it is obvious that there are some here who define a species very narrowly and would therefore treat the Kalhari desert people as a different species to the run of the mill European.
Even the word hybrid as applied to living organisms has major problems, especially when used in conjunction with some definitions of species.
The upshot of the various definitions is that any organism that breeds with another successfully and produces viable breeding offspring are members of the same species. In which case, Neanderthal is just one of the varieties of the homo sapiens species, no more and no less than any existing human today.
I have heard various comments about some people today of how like they are to the images we use for the Neanderthal. Since we only have skeletal remains and no actual corpses, there is much that we cannot tell about how they looked and how different any other bodily feature may have been. The experts use mostly guess work - I am not denigrating guess work based on good evidence. What I am saying is that we don't know with any certitude of the real differences, if any, between modern man and ancient man.
I think the labels aid in identifying migrations. i.e. This pattern of genes is called A and that other one is B. If you later see something that looks like a mixture of A & B then you know they interbred around that area at that time.
I think that we might really underestimate old branches of humans regarding how they developed.
Things like very simple trade, slavery and religious systems could exist in some primitive, chaotic way - that would explain a lot. We are walking into the dark and we will need probably decades before proper picture of ancient people will emerge. Hopefully, there will be enough funding to continue this.
traditional view is that before agriculture and animal husbandry slavery wasn't feasible - slaves would eat as much food as they would be able to collect, so why bother. Egyptian "living dead" term etymology as an example. But trade and religion, why not.
I think that such a slave could have many uses. Woman slave could be used for breeding and speed up the process of recovering heard numbers after some catastrophe. Also, it could be skill based - where slaves with unique skills would be traded (like making ropes, sharp objects, bowls), something that would be hard to grasp for ancient people.
There is also a "mule" thing, where slaves would be used for carrying stuff. And of course the last - religious. Could be that group would have a "different looking" person in a heard as a charm/talisman (breeding with it would result in healthy children - thanks to genetic diversity).
But it could be nothing. More research is important for sure.
