Back from the Holidays

The holidays came along just as this blog had reached its third month of operation, so I thought I would resume blogging by summarizing the scenario we have developed so far, keeping in mind that a scenario is not a theory, but a set of hypotheses. We can use them as a scafolding for organizing new data, and changing the scenario as new information requires.

5 million years ago: The last common ancestor of chimpanzees and humans lives. The ancestor was a knuckle walking, forest ape. The chimpanzee line continued on as forest apes, while the human line of descent pressed into woodland savanna.

5 million – 2.4 million years ago: The human line develops upright walking, possibly in response to the need to cover more ground in a less food-rich habitat. The known species from this period are various Australopithecus. There is continuing controversy of whether they were our ancestors or upright apes on a collateral line.

2.4 million years ago: The woodland savanna begins shrinking, being replaced by even drier prairie to which the human line was physically maladapted. Intellectually they were smart enough to discover ways of survival on the open lands, but they were also maladapted behaviorally. Instead of listening to one another’s discoveries, they were one more dominance-based ape species.

2.4 million – 1.8 million years ago: Homo habilis responded to the new niche by developing a larger brain. Probably as well, selective pressures led to a long juvenilization of the species, delaying sexual maturity and carrying forward into adulthood such childish behavioral traits as curiosity, emotional attachment, and more equal relationships. These traits provided the basis of the attention triplet (speaker, listener, and topic). Probably a few words were used.

1.8 million years ago: With the rise of Homo ergaster the human ancestral line was biologically and culturally adapted to its ecological niche, and had even spread quite far (some H habilis fossils have been found as far away as Indonesia). Probably at this point the chief biological adaptations at this point were concerned with the new behavioral niche, increasing the ability to pay joint attention to a topic.

1.8 million – 1.6 million years ago: Although we have no direct fossil or archaeological evidence on the matter, it is possible that syntax began to rise in this period by breaking words apart and substituting sounds. So if there was a word like tralala, it could be transformed into a string of words by changing tra to fa: fa lala. Indirect evidence of language’s progress consists of the way the brain continues to enlarge, advances in stone technology, and the spread of the population into a variety of ecosystems. The enlarged brain probably enabled attention to encompass a larger view (progress from “tunnel attention” to more modern attention), in which one word no longer satisfied the experience.

1.6 million years ago: Homo erectus appears.

1.6 million to 800 thousand years ago:  The brain continues to enlarge and Homo erectus spreads well beyond Africa, throughout Asia. Presumably the vocabulary now included many words, possibly several thousand, and there were a number of stock phrases that could take substitutions as needed and were remembered just as words are remembered, e.g., its mine, its big, its Jacks, its there; I wanna go, I wanna eat; I wanna ax, I wanna stick, I wanna a pieceameat.

800 thousand years ago: Homo heidelbergensis has the look of a late, European H. erectus or perhaps an archaic H. sapiens. It was larger than erectus, though not as large as a typical sapiens. Its brain was very close to that of modern humans.

800 thousand to 200 thousand years ago: This period likely saw the domestication of fire, and heaven only knows what those fellows talked about as they sat around a fire.

200 thousand years ago: Homo splits into two lines, sapiens and neanderthalensis. Both lines had similar brains. Neanderthal’s was slightly larger, but so was the body. Neanderthals also looked a bit more like erectus, with a protruding jaw, weak chin, and receding forehead. The changes in sapiens face may suggest further juvenilization. It was also about this time that the FOXP2 gene appeared among H. sapiens providing for clearer pronunciation and probably other things as well. (At the Stellenbosch conference there was some evidence that the gene is 2 million years older, but the documentation on that is still very fuzzy.)

200 thousand to 10 thousand years ago: The chief development over this period appears to have been characterized by ever-increasing attention to things outside the here and now. The archaeological data shows the earliest known remains of ritualized activity and representations of absent or imaginary things.

10 thousand years ago: With the rise of farming cultures and written language, the subject of this blog has definitely come to an end.

One area that is not addressed at all in this scenario is the rise of language as an instinct in infants. Before their first year is up infants have gone through a variety of apparently innate vocalizations. Autistic and deaf children babble, at least initially, suggesting the urge is very much an inborn thing. Maybe in the coming month this blog can make some progress investigating that.

Comments

[Jarod]

Very interesting,thanks!

[Juno888]

Great!..Very informative ...Thanks for it..