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Re:Fossils from Morocco complicate the story of modern humans by tombh on Monday September 11, 2017 @11:13AM (#15219083)
Coincidently 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 years ago and that our ancestors are from all the homo-inhabited regions of the world to a greater or lesser extent.

* Neanderthals and Denisovans are 2 known species that certainly inhabited much of the world (apart from the Americas) from around 2/300,000 to 50,000 years ago.

* We certainly bred with Neanderthals and Denisovans, some of us contain up to 4% of their DNA.

* Mammals generally take about 5 million years before they evolve far enough to be reproductively isolated. Of course before then there can still be breeding problems, for which there is evidence of in our breeding with the aforementioned.

* DNA from human skeletons several hunreds of thousands of years old can still be analysed.

* Mitochondrial DNA is passed by mothers only and so undergoes very little mutation. So it provides a stable and valuable signature for detecting ancient affinities between species/sub-species.

* By analysing the variation within genes certain characteristics can be interpreted like population size (eg; there were very few Denisovans) and that there are as yet unidentified species that humans have inherited from.

* Neanderthals possessed the FOXP2 gene known to be central in human speech.

* One of the oldest known oral traditions has evidence to verify a story from around 30,000 years ago: that Australian aboriginees brought the palm tree seeds with them from the north. See: http://www.abc.net.au/news/2015-04-03/aboriginal-legend-palm...

Forgive any errors in this amateur homework report.

Re:Fossils from Morocco complicate the story of modern humans by joshgel on Monday September 11, 2017 @02:05PM (#15220652)
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 by raihansaputra on Monday September 11, 2017 @03:34PM (#15221550)
I really really recommend the sequel of Sapiens, Homo Deus. I can't really describe it in words.
Re:Fossils from Morocco complicate the story of modern humans by evolve2017 on Monday September 11, 2017 @01:38PM (#15220389)
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 generating a cell's energy.
Re:Fossils from Morocco complicate the story of modern humans by gus_massa on Monday September 11, 2017 @02:14PM (#15220731)
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 by anderspitman on Monday September 11, 2017 @02:22PM (#15220805)
Saw this after I posted.
Re:Fossils from Morocco complicate the story of modern humans by anderspitman on Monday September 11, 2017 @02:18PM (#15220774)
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 by tombh on Tuesday September 12, 2017 @12:07AM (#15224745)
Diversity! Not mutation. Thanks for clearing that up. I'd edit my original comment if I still could.
Re:Fossils from Morocco complicate the story of modern humans by detritus on Monday September 11, 2017 @11:27AM (#15219228)
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! :)

Re:Fossils from Morocco complicate the story of modern humans by yuchi on Monday September 11, 2017 @11:34AM (#15219280)
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

Re:Fossils from Morocco complicate the story of modern humans by pamqzl on Monday September 11, 2017 @03:14PM (#15221347)
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.

Re:Fossils from Morocco complicate the story of modern humans by aaron695 on Monday September 11, 2017 @11:47PM (#15224671)
I wouldn't take it as 'extremely skeptical', it's fact that this is junk 'science'

We can look at story drift even in non primitive societies where they have writing and it's huge within generations.

Re:Fossils from Morocco complicate the story of modern humans by micheljones on Monday September 11, 2017 @09:44PM (#15224114)
Some tribes in north of Australia have verifiable myths about the geography of the lands that have been under the sea off the north of Australia for 6-8 thousand years at least (meaning, the description of the land features matches the sea floor geography).
Re:Fossils from Morocco complicate the story of modern humans by flukus on Monday September 11, 2017 @11:53PM (#15224694)
Has anyone quantified their myths properly? If not then they're just cherry picking.
Re:Fossils from Morocco complicate the story of modern humans by micheljones on Tuesday September 12, 2017 @02:26AM (#15225207)
Do you have any proof that they are just cherry picking?
Re:Fossils from Morocco complicate the story of modern humans by flukus on Tuesday September 12, 2017 @02:43AM (#15225275)
No, I just assume they are until they provide data to prove otherwise. We don't even know if the same tribes were in the same area that long ago.
Re:Fossils from Morocco complicate the story of modern humans by oh_sigh on Monday September 11, 2017 @01:06PM (#15220115)
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.
Re:Fossils from Morocco complicate the story of modern humans by micheljones on Monday September 11, 2017 @01:37PM (#15220376)
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 Persian gulf (which Eufrat and Tigris drain to currently, but used to be a fertile lowland with multiple rivers) cca 8kya.

https://www.livescience.com/10340-lost-civilization-existed-...

Considering the map in this article, with abundance of rivers across the whole Persian gulf plain, I would suggest that the myth of exile from Eden is also related to it - after the flooding and subsequent move of people upriver between the Eufrat and Tigris there was a need to create irrigation channels to keep the agricultural production up at necessary levels. Creating and maintaining these channels is hard, back-breaking work, and it might have inspired the famous 'By the sweat of your brow you will eat your food' line.

Re:Fossils from Morocco complicate the story of modern humans by kbenson on Monday September 11, 2017 @01:52PM (#15220530)
> 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 by flukus on Monday September 11, 2017 @08:28PM (#15223746)
I thought they were referring to the black sea deluge (https://en.wikipedia.org/wiki/Black_Sea_deluge_hypothesis). Some quick googling didn't reveal much, do we know when the persian gulf flooded?
Re:Fossils from Morocco complicate the story of modern humans by micheljones on Monday September 11, 2017 @09:53PM (#15224148)
No, I was not referring to the Black Sea deluge. That one is responsible for flood myths in Indo-European cultures (and also for the spread of the Indo-European cultures themselves), and it is more recent (6.5kya if I'm not mistaken).

The article I linked clearly states that it was a fertile land basin until 8kya. I decided to ignore kbenson's lack of reading comprehension hiding behind an attempt to insert himself as an arbiter through nitpicking about a thing he obviously knows nothing about, but I see he's not the only one refusing to read the article, so I'll restate my point:

My point of contention is the 15kya date. By 15kya the receding of ice age ice caps has barely started, so 15kya the ocean levels were not affected in any major way. The major geography-changing ocean level rise came a few thousand years later.

The linked article clearly states the following: "Then, about 8,000 years ago, the land would have been swallowed up by the Indian Ocean, the review scientist said." and "The Gulf Oasis would have been a shallow inland basin exposed from about 75,000 years ago until 8,000 years ago, forming the southern tip of the Fertile Crescent, according to historical sea-level records."

Re:Fossils from Morocco complicate the story of modern humans by kbenson on Monday September 11, 2017 @11:07PM (#15224511)
> I decided to ignore kbenson's lack of reading comprehension hiding behind an attempt to insert himself as an arbiter through nitpicking about a thing he obviously knows nothing about

While I see how it's possible you could interpret me as trying to insert myself as and arbiter instead of expressing my own lack of knowledge and asking for clarification, it was fully your own choice to not only decide that was the interpretation you believed as fact, but to then broadcast that negative interpretation as fact to others. A little assumption of good faith goes a long way, and I don't think it's too much to ask for.

Re:Fossils from Morocco complicate the story of modern humans by micheljones on Tuesday September 12, 2017 @02:25AM (#15225200)
You literally didn't read a very short article I linked in the comment you objected to; in that article the date of cca 8kya is mentioned at least twice very clearly.

But like I said, that's ok.

Re:Fossils from Morocco complicate the story of modern humans by micheljones on Monday September 11, 2017 @02:19PM (#15220778)
That's ok.
Re:Fossils from Morocco complicate the story of modern humans by posterboy on Wednesday September 13, 2017 @05:08PM (#15242705)
Maybe their digestive tract had carried the seeds ...
Re:Fossils from Morocco complicate the story of modern humans by tim333 on Monday September 11, 2017 @11:54AM (#15219447)
Minor correction - I think the chimp divergence was longer ago - Wikipedia: While "original divergence" between populations may have occurred as early as 13 million years ago (Miocene), hybridization may have been ongoing until as recent as 4 million years ago
Re:Fossils from Morocco complicate the story of modern humans by tombh on Monday September 11, 2017 @12:22PM (#15219663)
updated, thanks
Re:Fossils from Morocco complicate the story of modern humans by rgrieselhuber on Monday September 11, 2017 @04:13PM (#15221863)
Do you happen to have a good source handy on the growing acceptance of the Multi-Regional theory vs the Out of Africa theory? This is obviously a topic with political implications so looking for something that is accepted as a neutral source.
Re:Fossils from Morocco complicate the story of modern humans by danieltillett on Monday September 11, 2017 @04:56PM (#15222254)
It is not a case of one or the other, they are both right. All non-Africans are a hybrid between Africans and Neanderthals or Africans/Neanderthals/Denisovans.

You are right that this topic is politically sensitive - so sensitive that the data is basically ignored outside of science.

Re:Fossils from Morocco complicate the story of modern humans by nikcheerla on Monday September 11, 2017 @08:13PM (#15223672)
Why is it politically sensitive? I can't see any obvious political implications ...
Re:Fossils from Morocco complicate the story of modern humans by tombh on Tuesday September 12, 2017 @12:03AM (#15224732)
I'm not an expert, so just guessing, but I imagine it's something similar to the whole Arian stuff from the Nazis, ie: "look, our genes are more closely related to the most 'original' and 'pure' human lineage".
Re:Fossils from Morocco complicate the story of modern humans by tombh on Tuesday September 12, 2017 @12:01AM (#15224728)
A lot of the Multi-regional stuff I learnt is from the University of California Youtube channel. There's a playlist here, it's quite big, but a lot of relevant videos are in there: https://www.youtube.com/watch?v=v0j77rODO3E&list=PL1B24EADC0...
Re:Fossils from Morocco complicate the story of modern humans by BurningFrog on Monday September 11, 2017 @09:55PM (#15224165)
> We certainly bred with Neanderthals and Denisovans

Another way of looking at it is that we are the Neanderthals and Denisovans.

The Neanderthals population is estimated at 70,000 at their peak. At 2% of 7 billion, we Neanderthals are now two thousand times more plentiful!

Re:Fossils from Morocco complicate the story of modern humans by danieltillett on Monday September 11, 2017 @04:48PM (#15222171)
You missed what is probably the most important thing about human evolution and that is due to the rapid population rise after the invention of argriculture more human evolution has happened in the last 10,000 years than the previous million.

The other is that human population is filled with new genes that are under positive selection which have only partially spread through the population. Humans are probably the worst species to study genetically as all the normal assumptions you need to make don't hold.

One minor nitpick, your evidence of the oldest oral tradition is not very strong as there are only four major points on the compass. The likelihood of chance and cherry-picking is high.

Re:Fossils from Morocco complicate the story of modern humans by twelvechairs on Monday September 11, 2017 @06:02PM (#15222831)
> your evidence of the oldest oral tradition is not very strong as there are only four major points on the compass. The likelihood of chance and cherry-picking is high.

I think the point is that the palms are introduced (not native) more than their cardinal direction (i dont believe they were using a western compass at the time so as to have four directions)

Re:Fossils from Morocco complicate the story of modern humans by danieltillett on Tuesday September 12, 2017 @07:35AM (#15226438)
If you read the articles linked the evidence that this "knowledge" has been passed down for 30,000 years is not strong. Firstly, the palms are native to Australia, just other populations are found 1000 km to the north. Secondly, the palms have only being separated for 15,000 years at most. Thirdly, the northern evidence is actually "gods brought the palms from the north".