a bit of speculation

Many of you have already seen reports of Homo fossils recently discovered in Morocco.  (NYT:  https://www.nytimes.com/2017/06/07/science/human-fossils-morocco.html).  It is interesting for a few reasons.   One is that it pushes the origins back another 100,000 years to around 300,000.  The history of paleontology seems just about always that new discoveries push timelines further back, e.g., people in the Americas, use of fire.  These early Moroccans used fire, ate antelope and shaped arrow-spear heads using stone from 20 miles away.  Another find is that I used the plural, ‘origins’ indicating that scientists now think Homo arose not just in eastern Africa but in several areas, e.g., south Africa and now northwest Africa.  Still another is that the researchers say these fossils represent Homo sapiens, an assertion that will paleontologists will debate a good deal, I am sure.  The faces were flat like ours and some other features were similar.

512px-Craniums_of_Homo

We are #6, Moroccan closer to 5.

The interesting find is that their brains were about the same size relative to their bodies but were longer and less rounded in shape; our brains have some larger posterior areas that give height and round out our brain’s shape.

Lobes_of_the_brain

parietal in yellow, temporal in green, where they meet anteriorly is the place to be seen

Here is my speculation:   These areas still to develop probably included the parietal lobe and the part of the temporal lobe.  Consider what these enlarged areas help to accomplish.  On the left side the P-T (parietal-temporal) junction helps to maintain skilled motor patterns enabling handedness and motoric praxis, (this for right handed people) and just below that is an area involved in lexical memory, i.e., the ‘dictionary’ of words our brain relies on for comprehension (and some for production).  On the right side the P-T junction is where Empathy Central lies, or what academics call Theory of Mind.  This area supports our social insights and knowledge of others, and this in turn supports social praxis, i.e., socially skilled interactions.  These would seem paramount in our functioning and so the later evolution of this neurological substrate fits into this speculative hypothesis.  Finally, remember that the long cortical fasciculi, most notably the arcuate fasciculus (see several posts here about that fiber bundle) have their posterior origin in this area and their anterior origin in the frontal motor areas.  On the left we know this tract enables verbatim repetition, i.e., mirroring the words heard, and the right I suspect is involved in the empathic mirroring of emotional expressions.  Both types of praxis and mirroring are critical in the development of human intelligence.  Pretty cool, huh?  Well, much more to do today so I will travel on.

another date on the timeline

I have posted several times recently updating the timeline of humanity’s development. This primarily documents indirectly the rise of symbolic thought, which in my scheme presupposes a highly developed sense of empathy: why code and communicate symbolically what is in your MEMBRAIN’s interiority if you do not sense empathically that within the other’s MEMBRAIN their interiority ‘understands’ your meaning or import? Here’s another report pushing the timeline back and including Neanderthals.

Science News (4/18/15) reports that a paleontologist looked again at eagle claws recovered a hundred years ago from a cave dated to 130,000 years ago inhabited by Neanderthals (modern humans would not arrive in the area, as far as we now know, for another 60,000 years). He found evidence that these claws had been worked and probably strung together to form a necklace or some other adornment. Of course some say they did not necessarily symbolize something (and of course we do not know what) but this seems ludicrous. Maybe they put on jewelry mindlessly like Zsa Zsa Gabor but the rest of us humans don’t. This article has some other good details in it so check it out.

I looked back at some of my other posts to construct a proper timeline, remembering that some clerics (and many were of the intelligentsia of their day) tried to refute Darwin by pointing out that his theory on the origin of species would require many thousands of years, and they knew from studying the Bible that the earth itself was less than 10,000 years old (oops!). Darwin’s time was also the birth of modern geology so most intelligent people knew the earth was much older and now we know it is billions of years old with life developing in fits and starts over the majority of it. So a timeline is actually an important result of good science.

Before listing a summary from my more recent posts, here are some skulls of Homo genus (and they all were empathic and used some symbolization) with Mr/Ms Neanderthal upper right.

512px-Craniums_of_Homo

Check out these dates listed as years ago:

3 million—gene appears promoting brain enlargement

2 to 2.8 million—tools that were worked and shaped

1.8 million—fire and cooking (homo erectus)

500,000–phonological study’s estimate of origins of modern language

40,000 to 100,000—burials

45,000—paintings, good painting they are too

43,000—bone flutes

40,000—dogs domesticated

40,000—modern humans arrive in Europe

10,000—agriculture

9,000—dog burials (just found that one)

6,000—glyphs and a new learning curve

And so we travel on.