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New Study Shows Mystery 'Hobbits' Not Humans Like Us (phys.org)
According to a study published on Monday, diminutive humans that died out on an Indonesian island some 15,000 years ago were not homo sapiens, but rather a different species. The Homo floresiensis, known as "hobbits" since they looked like small humans, were found to be a distinct species based on the layers in the specimens' skulls. This discovery could be the end of one of the most heated arguments in anthropology.
So, they were called hobbits because they look like small humans. They are NOT humans, but they still LOOK like humans, just like Tolkein's hobbits (the commonest association), so the name is appropriate.
The archeologists who discovered the bones said it had all the hallmarks of a distinct homo species right from when they first discovered it. They published papers to that effect 10 years ago. This was however controversial due to the very young age of the bones. No other homo species except us is known to have survived past the last ice age, the claim that these did - and were not the same species as us - was very controversial. Especially since the fossils were so recent that it is entirely possible that humans could have encountered them (remember - most dead bodies don't leave fossils - if the fossils we have is a mere 15-thousand years old, they could have been alive as recently as 5000 or even 1000 years ago).
So a lot of scientists were understandably skeptical about their conclusions even though they were seriously thorough, they didn't publish their findings for almost two years after the discovery as they spent all that time checking and rechecking to test every likely counter-theory and only published it when all those tests were negative and they could find no other possible explanation.
That it remained controversial despite that just shows that contradicting pet theories can upset people - and sometimes, the pet theories are wrong. Interestingly, if any homo species was going to survive the ice age without our technology these guys had about the best shot. Living on a small tropical island - they probably barely even noticed it happened.
Unicode killed the ASCII-art *
The recent developements in average height, as well as within the next 100 years are not due to genetics. The timeframe for that is much too small to affect a huge population in the 100mio significantly.
They are mostly attributed to better food, lack of child deseases and (debated) growth hormons in food or other industrial substances that may have the same effect.
I wish I had mod points for this.
One question, though. Did you really mean to talk about "archaic species" if they were close enough to interbreed and re-merge? I understand that there are lots of subtleties, but the concept of species as lines distinct enough not to interbreed was drilled into us pretty heavily at school...
I may have used the term species a bit loosely but that also brings us to an interesting question. When have two groups of a species 'evolved apart' enough to be considered separate species? Turns out there is no hard and fast definition of this. In the old days this was done by analysing morphological differences of animals, however, recently it turns out that animals we thought were unrelated were actually genetically rather closely related or vice versa so morphology is not the best determinant all on it's own. In my opinion you have got two different species when the difference in their DNA is so great they can't produce live offspring and the ability to produce infertile offspring is then the transitional state. This means that genetics and not morphology is the best way to classify species and that is controversial. But morphology cannot be ignored. There are also cases where two different animal groups cannot practically mate due to anatomical differences even though one may be able to interbreed them in a petri dish and produce live, and even fertile offspring via artificial implanting of embryos. Are those separate species? It'a a matter of definition. Neanderthals for example are referred to as a 'species or subspecies of human in the genus Homo' in the Wikipedia article i.e. scientists are still bickering about whether the Neanderthals should be called Homo Neanderthalensis (species) or Homo Sapiens Neanderthalensis (subspecies of H. Sapiens). Personally I'm inclined to go with "can no longer produce offspring or only produce sterile offspring" as being the point when you get a new species and that still leaves us with the problem of defining a sub-species. According to geneticists Neanderthals and Modern humans were rather close to this point when the interbreeding events took place but they were still able to produce fertile offspring or we would not be carrying around H. Neanderthalensis and H. Denisovensis DNA now would we?
Species are generally considered to be separate if they can't breed to create FERTILE offspring. Lots of closely-related species can breed, but the offspring are usually sterile.
Usually sterile, but not always, and not always to the same degree. And therein lies the rub: placing a thing in one category or another implies the difference is discrete and readily observable, but in the cases of populations of organisms differences are along a continuum.
The way high school students are taught about what a species is is simplistic; or at least it seems to be to me after years of working with scientists to support their data needs. I believe you can think of the concept of "species" as describing, not just a population of organisms, but a population of researchers studying those organisms. A taxonomic designation is a tool researchers use to communicate with each other; a division of a population into two species is dependent upon the their communication needs, not some kind of objective Truth.
Inability to crossbreed to produce fertile offspring is certainly one thing that researchers need species to tell them; if two populations can't interbreed then that will certainly force researchers to distinguish between them. But there are other reasons to recognize new species, and I've certainly seen cases where populations that can interbreed to produce entirely viable offspring have been put into two different species. Let me tell you that's a PITA for people who are keeping records. "We collected species X, species Y, and what appears to be an X/Y hybrid..."
It would be really nice if there were some simple, objective, observable criterion for generating a new species designation, but that's not how it works. The way it actually works is some journal editor accepts an article describing the proposed new species. Then after the ensuing argument a consensus is formed that some people like, some people dislike, but most people can live with. It's a matter of how people feel about the impact of the new species on their work, not some objective distinction -- although because objective distinctions like physical traits are involved I think researchers sometimes lose sight of the fact that naming a population with those traits is a mere convention. It's easier to see the essential arbitrariness of the process when you're sitting off on the sidelines watching.
So bottom line: "species" reflects the needs of researchers to communicate with each other, not some kind of objective reality. Reality can force researchers to recognize a new species, but it can't prevent them from doing that.
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Especially since the fossils were so recent that it is entirely possible that humans could have encountered them (remember - most dead bodies don't leave fossils - if the fossils we have is a mere 15-thousand years old, they could have been alive as recently as 5000 or even 1000 years ago).
An encounter with modern humans is very likely. The people on the next island has folklore telling of small people in the "hobbit island". It has detailed descriptions, some with match the bones and some which can't be seen on the bones. For instance the women had long saggy breasts and to get around, they hung them on the shoulders. The folklore is mainly centered on one fact and that is those small people were extremely aggressive and they would likely kill you if you would be stupid enough to go to their island. In other words like most folklore it's a warning of "if you do this, you die", though this one might be even more accurate than most.
In Japan folklore tells of evil beings living in mountains and stuff. A good example is a mountain with a monster (forgot the Japanese names, sorry), which eats all the people it can find. In modern times the same mountain is a no-go area. Heavy rain is frequent even if the weather is good when you leave home and dying of hypothermia is a real risk. Being covered with a dense forest, dead people are unlikely to be found and even less likely considering people are warned not to go there (no traffic or local population). This mean while the explanation in the folklore is incorrect, the fact with "if you go there, you have a high risk of vanishing without a trace" is true. In other words, there is a real warning hidden inside the fairytale.
Also fairly recently scientists revealed that the terrain in the north west US was made when an inland sea bursts through a wall of ice when the ice age ended. When presented to the locals, a native to the area said "great lecture, but we knew it already. The folklore told us of this event" and digging into that aspect of the story, the folklore told of a strong flashflood washing away all tribes who didn't make it to the hilltops. Further upstream the wall itself was in the folklore and how it was a disaster that the inland sea vanished for all the tribes feeding on the fish. Gathering all the folklore came to the same conclusion as the university study of the terrain and all the info matches up.
Considering modern humans spread to Indonesia and reached Australia 50k years ago, we know from the date of the bones that they must have been in Indonesia at the same time at some point, possibly for many years. Indonesia is a big place, which makes it hard to proof that they encountered each other, but the window of opportunity is quite big. With no media or knowledge of foreign influence, the evenings were free to talk about folklore and common knowledge. A record of a major event like a different human species would live on forever and 15k years ago isn't even far from the report of the end of the ice age in North America.
Conclusion: if the folklore tells that modern humans encountered the hobbits, they most likely did. Remember folklore is to people without a written language what history books are to us. This mean if the folklore matches the modern findings, it's a good chance it's not just by chance. It would be reasonable to say "it's most likely like that" until proven otherwise.
...It's not perfect because some closely related species such as horses and donkeys can produce offspring ans sometimes those offspring are also fertile.
And it only takes this happening once where that fertile offspring survives and a whole bunch of others are wiped out that the fertile offspring then generates significantly more DNA into the pool. Note that in this case it is likely male children or the female child(ren) of a homo sapiens female that were fertile and passed on the Neanderthal DNA, due to the current lack of observed Neanderthal mitochondrial DNA. Same for the Denisovans, etc. That interpretation is open to future data proving it wrong as more DNA analysis of the population as a whole proceeds.
The cesspool just got a check and balance.