The question is not only a poetic one, thinking about early romances across the borders of tribal wars and what ever some poets might imagine. No the question is deeper, or at least more troubling for some, more interesting for others. It's orbits mainly 2 points:
- A strictly scientific question:
Let's remember the definition of species:
- Wordnet: taxonomic group whose members can interbreed
- Wikipedia: In biology, a species is, loosely speaking, a group of related organisms that share a more or less distinctive form and are capable of interbreeding.
You can search more definitions, you know the procedures type "define:species" and you'll get a myriad of definitions, however an important detail will certainly repeat itself in all definitions: Interbreed, Interbreeding. Fore this is an important detail about naming species, two ordinary individuals that are grouped in one species need to be able to interbreed in order to belong to the same species. However, some scientists tend to put the modern human and the Neandertal human in one species: Homo sapiens. In that perspective, the modern human would be Homo sapiens sapiens and the Neandertal human would be Homo sapiens neandertalensis. Could that be true?
We certainly have no way to reach a sexually functional Neandertal in order to try and make it fuck a human and then see if they give a healthy, fertile offspring (keep in mind that many animals belonging to two different species may breed but their offspring is sterile there fore the process is scientifically a failure). But modern day scientists don't always refer to actual interbreeding to define species, they use molecular biology and genetic studies of the genome and so on. But even that is useless as the sample of Neandertals are rare (same as any ancient human remains) and when we do find some remains, it's usually bones, and even when we do find remains of soft tissues it's usually mineralized tissues and not mummified tissues... In other words we have no material to extract DNA from, some studies did find a few fragments of DNA but that hasn't been able to clear the question of whether neandertals and modern humans belong to the same species or not.
But many scientists already speak of Homo sapiens neanderalensis... Which brings us to another point that is less scientific, but more philosophical and existential...
- What is a Human?
Of course, if you do sink deep into Paleoanthropology and evolution in general, humanity will lose its spark and it will make Man the special creature of God... it will make him just another animal. I don't know whether it's insulting or relieving to acknowledge that but for most people it's simply disturbing! But so far we did preserve a small shred of superiority: We, the Homo sapiens, have ruled the world with our wit and intelligence.
But what if We didn't rule it? What if other humans have ruled it with us? What if we were not pure Homo sapiens what if we were a mix of humans and that other humans rule the earth together with the combination of all our genes. Of course some might argue that we don't look like neandertals or like Homo ergaster or any other humans. But the truth is that Phenotypes (looks) are deceiving we can hold more DNA from Neandertals than we do from Homo sapiens and still look like the latter. Because different pieces of DNA fulfill different roles. If that is true then we would have nothing, and I mean, NOTHING, that sets us apart from other animals.
I know many of those who follow my blog may not find this so shocking or so disturbing. But come on people we might not be the world's number 1 believers, but many people around the earth are strong believers and many of them believe that God created all animals in one day and MAN on a totally other day. Many people justify their right to kill animals because they are...animals... not Humans...not special enough.
I have been trying to follow the news of this subject for nearly 2 years now, reading every article about it. And finally I have found a study that claims to have some rational answer to that question. You can read it in the Scientific American Online edition.
The article focuses on the fact that humans did in fact expand to the world starting from Ethiopia (Africa), which is no longer seriously questioned by scientists. In proving their point they rely on the decline of variability in skull structure from the cradle of modern humanity (Ethiopia) to the farthest regions (Asia for example). However here's the piece that interests us:
As smaller bands broke off from larger settlements, they would have carried with them a less diverse subset of the bigger group's genes, which partly translate into anatomical features such as skull shape. So the farther early Homo sapiens trod from their homeland, the less variable their skulls should become. Unless, that is, they bred with previously established populations of Neandertal or other early humans, which would have injected new genes and boosted variability.
The researchers found no signs of interbreeding, they report online today in Nature. "What you find is a very nice linear decline of variability as you move farther away from Africa," Amos says. Prior studies had identified an identical trend in the diversity of simple genetic sequences or markers.
So maybe religious lunatics can sleep well tonight... We didn't interbreed with Neadertals. But that leaves an important question yet unanswered:
Was it biologically impossible for us to interbreed?
Just because we didn't interbreed with them doesn't mean it would have been impossible. One thing is certain, we had all the chances to do so. The variation of weather over the last 100 000 years (modern Man's appearance is estimated to around 120 000 years) have defined many regions of crossing at least between modern man and Neadertals. The most important region being the Middle East in which I live. Unfortunately, studies in here are rare, the only place where serious scientific research takes place is Israel (the only place where an abundance of remains was found, though Lebanon for example contains many caves, thus must've had many remains).
On the other hand, knowing of how humans are xenophobic by nature (check out this article in National geographic news). You can't help but to think to yourself: Both groups must've forbidden such contact between different members, probably declaring it a sin or something and promoting the others' mass murder.
I strongly believe that