I was always surprised by the tendency of anthropologists to assign hard evolutionary 'milepoints' based on the very limited set of archeological data. Most egregious example is 'behavioral modernity' theory which claims that homo sapiens developed language, culture and art only relatively recently (30kya) because that's how old the currently oldest archeological finds of culture/art expression are. This doesn't stand up even to the simplest application of Occam's razor.
Fossils from Morocco complicate the story of modern humans
21–30 of 58 posts
Re: Fossils from Morocco complicate the story of modern humans
#22The San people of southern Africa are claimed to be the living human group with the most ancient divergence from the rest of humanity, around 200,000 years ago. That they are so similar to the rest of humanity has always made me wonder if the commonly accepted divergence date ranges should be pushed back. From the Wiki: "A DNA study of fully sequenced genomes, published in September 2016, showed that the ancestors of…
Not only that, their divergence date (cca 175kya-200kya), combined with the fact that they have language, culture and art disproves the 'behavioral modernity' theory which posits that human brains evolved to use language and produce culture and art relatively recently (30kya) based on the oldest currently available archeological finds of expressions of culture/art.
Re: Fossils from Morocco complicate the story of modern humans
#23Earlier quoted context omitted.
On a similar timescale, lots of cultures from the middle east have a flood myth, which is thought to be a real event from about 15k years ago.
I'm sorry, but that statement is very likely incorrect. 15kya was very soon after the last glacial maximum (24-18kya) and sea levels weren't significantly affected by then. The receding of the ice sheets started at cca 18kya, but was going slowly at first and only accelerated after 15kya. Most of middle east cultures draw the myth from Mesopotamian cultures, whose flood myth most likely refers to the flooding of the…
> Most of middle east cultures draw the myth from Mesopotamian cultures, whose flood myth most likely refers to the flooding of the Persian gulf
I thought the GP was actually referring to this event. Do we have a time frame for that which negates that possibility, because otherwise I'm not sure how your evidence refutes rather than corroborates.
Re: Fossils from Morocco complicate the story of modern humans
#24Coincidently I've been reading and youtubing about human evolution recently. If anyone's interested here are some bullet point facts that may surprise other laymen. * In the last few years the Out Of Africa theory (modern humans originated solely in Africa) has received stiff competition from the Multi Regional theory. Namely that waves of human species have left Africa since we diverged from chimpanzees 4 million ye…
I'm reading the book Sapiens right now, which I highly recommend. Lots of interesting facts. But also a broad explanation of the theory of human development.
Most interesting fact I learned: At one point there were as many as 6 human species (Homo sapiens, homo errectus, etc) on earth at the same time!
Re: Fossils from Morocco complicate the story of modern humans
#25Coincidently I've been reading and youtubing about human evolution recently. If anyone's interested here are some bullet point facts that may surprise other laymen. * In the last few years the Out Of Africa theory (modern humans originated solely in Africa) has received stiff competition from the Multi Regional theory. Namely that waves of human species have left Africa since we diverged from chimpanzees 4 million ye…
Very interesting! I'm not sure I agree with your reasoning for the mitochondrial mutation point: > * Mitochondrial DNA is passed by mothers only and so undergoes very little mutation It's true that mothers pass on mitochondrial DNA but this doesn't necessarily require the absence of mitochondrial DNA mutations. I would imagine the lower rates of DNA mutation are due to the importance of the mitochondrial genome for g…
The mutation rate of mitochondrial DNA is much faster than in nuclear DNA [1]. But mitochondrial DNA does not have crossover, so the mutation tree is much easier to build.
[1] From: https://en.wikipedia.org/wiki/Mutation_rate#Variation_in_mut...
> Human mitochondrial DNA has been estimated to have mutation rates of ~3× or ~2.7×10−5 per base per 20 year generation (depending on the method of estimation); these rates are considered to be significantly higher than rates of human genomic mutation at ~2.5×10−8 per base per generation. Using data available from whole genome sequencing, the human genome mutation rate is similarly estimated to be ~1.1×10−8 per site per generation.
Re: Fossils from Morocco complicate the story of modern humans
#26Coincidently I've been reading and youtubing about human evolution recently. If anyone's interested here are some bullet point facts that may surprise other laymen. * In the last few years the Out Of Africa theory (modern humans originated solely in Africa) has received stiff competition from the Multi Regional theory. Namely that waves of human species have left Africa since we diverged from chimpanzees 4 million ye…
Very interesting! I'm not sure I agree with your reasoning for the mitochondrial mutation point: > * Mitochondrial DNA is passed by mothers only and so undergoes very little mutation It's true that mothers pass on mitochondrial DNA but this doesn't necessarily require the absence of mitochondrial DNA mutations. I would imagine the lower rates of DNA mutation are due to the importance of the mitochondrial genome for g…
I would expect the mutation rates of mitochondrial and nuclear DNA to be about the same, unless the mitochondria have additional repair proteins not involved with nuclear DNA, or the shorter length of the mitochondrial chromosome affects the rates, or some other process I'm not familiar with. I think maybe parent meant to refer to diversity, not mutation. With nuclear DNA, the offspring chromosomes are made up from a combination of the parents' DNA. There's a lot of swapping and mixing and matching that takes place. This adds diversity to the population.
Re: Fossils from Morocco complicate the story of modern humans
#27Earlier quoted context omitted.
I'm sorry, but that statement is very likely incorrect. 15kya was very soon after the last glacial maximum (24-18kya) and sea levels weren't significantly affected by then. The receding of the ice sheets started at cca 18kya, but was going slowly at first and only accelerated after 15kya. Most of middle east cultures draw the myth from Mesopotamian cultures, whose flood myth most likely refers to the flooding of the…
> Most of middle east cultures draw the myth from Mesopotamian cultures, whose flood myth most likely refers to the flooding of the Persian gulf I thought the GP was actually referring to this event. Do we have a time frame for that which negates that possibility, because otherwise I'm not sure how your evidence refutes rather than corroborates.
That's ok.
Re: Fossils from Morocco complicate the story of modern humans
#28Earlier quoted context omitted.
Very interesting! I'm not sure I agree with your reasoning for the mitochondrial mutation point: > * Mitochondrial DNA is passed by mothers only and so undergoes very little mutation It's true that mothers pass on mitochondrial DNA but this doesn't necessarily require the absence of mitochondrial DNA mutations. I would imagine the lower rates of DNA mutation are due to the importance of the mitochondrial genome for g…
The mutation rate of mitochondrial DNA is much faster than in nuclear DNA [1]. But mitochondrial DNA does not have crossover, so the mutation tree is much easier to build. [1] From: https://en.wikipedia.org/wiki/Mutation_rate#Variation_in_mut... > Human mitochondrial DNA has been estimated to have mutation rates of ~3× or ~2.7×10−5 per base per 20 year generation (depending on the method of estimation); these rates a…
Saw this after I posted.
Re: Fossils from Morocco complicate the story of modern humans
#29The San people of southern Africa are claimed to be the living human group with the most ancient divergence from the rest of humanity, around 200,000 years ago. That they are so similar to the rest of humanity has always made me wonder if the commonly accepted divergence date ranges should be pushed back. From the Wiki: "A DNA study of fully sequenced genomes, published in September 2016, showed that the ancestors of…
Do you know if they are related to the Berbers?
Well, we are all related to each other, the only question is how _closely_ related we are. And as for that, any non-Khoisan/non-Pygmy human subgroup is more closely related to any other non-Khoisan/non-Pygmy subgroup than they are to Khoisan or Pygmy people. In other words, Khoisan and Pygmyies are the most distant cousins to all other homo sapiens (diverged from us 175-200 thousand years ago).
Re: Fossils from Morocco complicate the story of modern humans
#30Earlier quoted context omitted.
Wow. That last bullet point is particularly remarkable to me - both the implied level of 'technological understanding' and presumed foreplanning for significant journeys 30K years back and for the capacity of oral history to record what come today might not be the most pertinent information. Also quite amusing in the context of contemporary Australia's philosophy where alien plants and animals are concerned! :)
Citing that article: > “It suggests that Aboriginal oral traditions may have endured for up to 30,000 years, and lends further weight to the idea that some Aboriginal myths pertaining to gigantic animals may be authentic records of extinct megafauna” Wow ^ 2
I'm always extremely skeptical when someone suggests that oral traditions could possibly have survived for long periods of time. That's twelve hundred generations! Given what we know about the speed at which Chinese Whispers tend to drift, the idea that any story can last 1200 generations is an extraordinary claim that demands extraordinary proof.
Hundreds of Aboriginal tribes had hundreds of contradictory myths on hundreds of subjects. Most of them are verifiably false (e.g. those rocks over there are not, in fact, the remains of three young women who got turned into stone for disobeying their father). Some of them are probably correct by complete accident.
As for gigantic animals... well, they're a pretty common motif in myths and stories all around the world. Maybe it's some distant memory our cultures all have of the larger animals that used to live around here... or maybe it's just because giant animals are cool. In Aboriginal myths, giant animals are often really really giant, because they're used as explanations for geographic features -- e.g. rivers are caused by the meanderings of a giant snake.