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View Full Version : Out of Africa a bit earlier than once supposed


Lonewolf_50
26th Jan 2018, 19:14
The archaeology world seems to be resetting a few assumptions.
Up to a few days back, the best guess time for the migrations of humans out of Africa was about 90-100,000 years ago. Based on some finds in Misliya cave (not far from Mount Carmel in Israel) they are recalibrating that to around 175000 - 200000 years ago as the migration time frame.


While the video alludes to the migrators interbreeding with, or displacing neanderthals and other groups of related proto humans, I'll need to dig around for stuff in writing to get a better sense of what this find means.

Fossil changes everything we knew about spread of humans out of Africa (http://www.msn.com/en-us/video/wonder/oldest-human-fossil-found-outside-of-africa-means-we-migrated-earlier-than-we-knew/vi-AAvaKGl?ocid=ientp)


Here's an article from Nature (https://www.nature.com/articles/d41586-018-01261-5).
However, recent discoveries have muddied that simple narrative. Some H. sapiens-like fossils from Morocco (https://www.nature.com/news/oldest-homo-sapiens-fossil-claim-rewrites-our-species-history-1.22114) that are older than 300,000 years, reported last year, have raised the possibility that humans evolved earlier and perhaps elsewhere in Africa. Teeth from southern China (https://www.nature.com/news/teeth-from-china-reveal-early-human-trek-out-of-africa-1.18566), described in 2015, hint at long-distance migrations some 120,000 years ago. And genome studies have sown more confusion, with some comparisons of global populations pointing to just one human migration from Africa, and others suggesting multiple waves.
Been doing some reading on Bronze age, and pre bronze age artifacts, languages, and cultures and how those inform the conclusions archaeologists draw on migration patterns in those eras.


Perspective: insofar as history goes, our "modern" conception of cities and civilization goes back to about 4000ish BC, though smaller settlements (of a permanent sort) are certainly in evidence in Europe a few thousand years before that. (Danube cultures before writing). Looking at how slow things change, you've got a rest of 50,000 years, which is about ten times the length of modern civilization.


People were hunting and gathering for a very long time.

Interesting stuff, and a great find, albeit in a far deeper era of human history.

G-CPTN
26th Jan 2018, 20:12
When you consider the number of people who have lived and died, it is strange that there is little evidence left of the early migrants.
Did they travel in single numbers, or in hoards like the recent influx into Europe from Africa?
Were all the bodies buried? Have they decayed away to dust?

Eddie Dean
26th Jan 2018, 20:25
The minimum requirement for the success of a population is twelve couples.

sitigeltfel
26th Jan 2018, 20:30
The minimum requirement for the success of a population is twelve couples.

Would you Adam and Eve it!

;)

uffington sb
26th Jan 2018, 20:46
Wouldn’t that be an orgy?

Lonewolf_50
26th Jan 2018, 21:03
Did they travel in single numbers, or in hoards like the recent influx into Europe from Africa?
Were all the bodies buried? Have they decayed away to dust?

I would expect that they'd travel in family groups, upping to clan and tribe depending upon how successful that group is in increasing in size over a few generations.

It is not strange that they left little evidence. Cities and towns are an innovation within the last 10,000 years or so. If you look at the steppes between the Black Sea and Caspian, you have a lot of nomadic sorts who move with the seasons. Finding their leavings is hard. See also the plains Indians as compared to the Navajo and Pueblo in the US.

419
26th Jan 2018, 22:41
When you consider the number of people who have lived and died, it is strange that there is little evidence left of the early migrants.
Not that strange if figures such as this are to be believed:
Re: What percentage all living remains eventually becomes fossilized? (http://www.madsci.org/posts/archives/1997-08/871343510.Ev.r.html)

Biologists estimate that there are around 1,000,000 living species of animals. Because invertebrate life appeared on earth more than 500 million years ago, paleontologists estimate that extinct species have an aggregate of at least 100 times that number.

Of the 100,000,000 extinct animal species, only around 100,000 species have been discovered and described. That means that only around 1/10 of 1% of all animal species that have ever lived have been discovered! (And remember that each species may be represented by hundreds of millions of individuals.)

Ivana Kransky
27th Jan 2018, 12:41
Discoveries like this make me wonder if our version of humanity is even remotely accurate.
All the stuff we are taught in school and that which we read in books written by those that specialise in this subject are in a large way assumptions and theories and beliefs.

Consider this...
In the last 100 years we have gone from sail/steam ships and horse and carriage to 1000s of jet aircraft crossing the continents daily , nuclear submarines that can stay submerged for 3 months with 100 crew , electronic tech so well progressed that we practically all carry a super computer in our pockets and what about the leaps in medicine ?

Now....
A quick look on the interweb will show us that dead animals , humans included will over time completely disintergrate and basically revert to its component elements.
If we look at our structures today, which of them could we say if left unattended and unmaintained for a 1000 years would still be recognisable now think of leaving it for maybe 25000 years ?
Im fairly sure that no houses or bridges or roads could stand the wear and tear of the 4 seasons including wind and rain for 25000 cycles and with the exception of a few well protected or over engineered structures practically everything we have built or made everything that would prove our advanced degree of development as a species of earthly inhabitant, could conceivably be eroded rusted cumbled reverted back to the dirt from where it came.
When i hear geologists talk of things like continental plate drift and the time it takes for Geological features like the grand canyon or the hawaiian islands to form i realise how as modern humans we are such a recent arrival such a speck in time in geological time frames.
We are guessing wildly when we start altering the theory of african mans migration time by 20-50,000 years Because it changes the very timelines of our theory of evolution.

Many years ago i was involved in providing helicopter support for a mining exploration crew.
Basically flying core samples away for examination in a private laboratory.
One night there was suddenly much activity around the drill head, apparently at around 3000 meters the core samples were littered with fragments of metal and closer examination showed folds and joins clearly indicating (to me) manufacture rather than a natural occurance. Not much sleep was had that night as several of us pondered the possibilities behind this discovery and then during our wide eyed discussions the on site geologist pulled out some pictures she had taken of cores from another location and clearly visible was a layer of assorted bone fragments recovered from a similar depth.

how did what looks to be manufactured metal come to be buried 3km deep? How long does it take for bones to be covered in so many layers of dirt that they end up 3 km down ?
Could it be that the fossilised stuff we are finding and have found so far are only the more recent and therefor closer to the surface?

What happened in the period between the end of the dinosaurs and our estimates of the first humans ? Our scientists best estimates still leave a fudge factor of tens of millions of years seperating the various prehistoric periods from the others, civilisations could have risen and fallen and been erased entirely in that time.

Sometimes i cant help but be sceptical of huge revisions of previously concrete facts based on the discovery of a tooth or jawbone.
We know so little of the times passed we have theories and concepts of how things were before our time but its all based on bone chips and fragments of artifacts.

If a significant global event were to occur today and snuff out all but a few remote tribes in the amazon or papua new guinea then 50-100,000 years would easily erase all our modern constructions.
What if the primitive survivors were given that time to evolve and develop ? Would the cycle start again ? Has it happened in the past ? What about the human genetic bottleneck 50000 years ago what caused that and has it happened previously as well ?

We know so little of our origins.

I suspect any discovery that drastically alters our mainstream beliefs of humanity and evolution would be reburied or destroyed pronto.

Cc: Ridley Scott

Traffic_Is_Er_Was
27th Jan 2018, 13:44
People were hunting and gathering for a very long time.
If left isolated, in small enough numbers, and without pressure from external competition, there was probably no need to "evolve". Witness Australian aborigines. Basically stone age, nomadic hunter gatherers for the past 40-60 (depending on who you believe) thousand years.