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Selected Books by Edmund Blair Bolles

  • Galileo's Commandment: 2500 Years of Great Science Writing
  • The Ice Finders: How a Poet, a Professor, and a Politician Discovered the Ice Age
  • Einstein Defiant: Genius vs Genius in the Quantum Revolution

« Avoiding Extinction | Main | Spear Carrying Chimps »


John Blake

Some 72,000 - 75,000 years ago, the Toba Eruption in Indonesia left a crater eighty miles long by fifty miles wide. Akin to a moderate meteor-strike, this geophysical catastrophe all but extinguished modern-day primates (evolving "Homo sapiens"). We need not adduce any fancy bio-evolutionary mechanisms: All but a few hundred breeding pairs survived, huddled behind the Central African massif crowned by Kilimanjaro on the East.

This near-eradication accounts for the human species' extraordinary genetic homogeneity: From a minuscule basis, "genetic drift" over a mere 75,000 years has necessarily been minimal. More interesting, though mankind's racial diversity may be genetically marginal, it seems that qualitative aspects outweigh mere quantitative factors.

Call "qualitative" what you will, it's not just Neanderthals and perhaps related strains that suffered in relation to Homo's rapid divergence "out of Africa", filling ecological and evolutionary niches vacated in Toba's great die-off. Above the Northern Mediterranean, more challenging environments than African savannahs apparently fostered aggressive socio-cultural, even intellectual development. Fuss and grump you may, but the historical record stands. Migration left Africa behind.

Academics unaware of determining factors beyond their blinkered specialities wax over-confident in
predictable ways. Let's just say, they ignore larger realities at peril.

The current contretemps over "global warming" is analogous to 60-year controversies attending Alfred Wegener's hypothesis of Continental Drift. Assuming continental land-masses were identical to ocean bottoms, geophysicists pooh-poohed Wegener
until the mid-1960s, when deep-ocean probes resolved that Africa had indeed split off from South America. In brief, today's missing element is deep-ocean volcanism, dating from at least 1850 but discovered worldwide (in Arctic, Indian Ocean, Pacific Rim) only since 2001.

Ocean warming drives evaporation, an air-conditioning (cooling) effect that occasions heavy atmospheric precipitation-- cold rains in summer, massive snowfalls in winter. As a volcanic effect, surging CO2 levels aggravate cooling by pyramiding warm-water evaporation. Glaciers do not move south: They land on our heads with 90-foot snowfalls, whose albedo then shifts warm-water currents like the Gulf Stream hundreds of miles south.

Bingo-- Ice Age, persisting 120,000 years. Over the last 10-million years, interglacials have lasted 12,000 years on average. We are now 12,500 years past the Younger Dryas... and there are other factors, intra-solar and cyclical from 1313 to 2113 which do not augur well.

Where once the Toba Eruption defined humanity's genetic makeup, we now face a perfectly standard Ice Age. If not our children, our grandchildren may face extinction as populations war for climate-zones still cultivable. But we ourselves will be dead, and the World thereby a better place. Tamam!
BLOGGER: Thanks for this post. It feels like a real contribution of the sort I would love to see as a regular part of this blog.


Interesting timeline/migration model.

There can be no doubt that the Toba eruption was a massive event that must have had a massive impact.

Alan Poirier

If we think of language as purely communication, then we miss another important aspect of language -- it helps define reality.
In other words -- pun intended -- language is a way of visualizing the environment.
The evolution of language, in that respect, is no different than the evolution of any of our senses. It is our senses and the brain that interprets those sensations that allows us to interact with our environment and thus survive.
So a worm than can distinguish light from dark can exploit his environment in a way that a blind worm cannot.
It's no different with language. The evolution of language allowed homo to create a representation of the world (his environment) that was fundamentally different than any other animal inasmuch as it was symbolic and full of metaphor -- powerful tools in the a rapidly growing toolkit of early man.


Surely metaphor is older than language. The whole notion of embodied cognition does not rely on language and yet is the (it seems to me) obvious source of metaphor. And the notion of categorization, which has been shown in many animals, (it seems to me) is the obvious source of symbolism. Of course language has changed how we can think and made metaphor and symbolism more powerful tools, but lets not get carried away and assume that they cannot exist without language.
BLOGGER: Can you give us an example of a metaphor that might predate language?


Examples of metaphor that predates language:
I am not saying that metaphor itself, in its strictest meaning, is pre-language, but that it appears to be a natural outgrowth of embodied cognition. An example of embodied cognition is the relationship between cold temperature and cold social relations. So if someone is actually feeling cold, they tend to feel socially distant from others and if they feel socially distant from others, they feel physically colder. There are more and more of these instances of embodied cognition being examined and published in papers these days. This effect does not require language but it does connect an abstract idea with a physical bodily feeling. Now take a metaphor like 'life is a journey' and it can be put in a train of metaphors, each more elaborate than its parent metaphor, that rest on the simple motor act of movement. The ideas of starting place, path, destination do not have to be verbal. A baby can be motivated to crawl from one place to another before it has language to describe that movement.
I would guess that all our words, concepts, ideas, and symbols have grown out of elaboration (in a metaphorish way) from the simplest motor actions and preceptions, ie embodied cognition.
As usual, I am not that interested in the uniqueness of language but it what can connect the development of language with what came before it. I am trying to avoid the 'with one mighty leap' explanations.
BLOGGER: OK, I see what you mean. You are talking about the synethesia side of perception: bright sounds heavy smell, cold look ... etc. It's a good clue to where some metaphors come from, but I guess we'll never know if say apes think that way.

Alan Poirier

I doubt that metaphor could precede language. Even at its most elemental form, metaphor is symbolic thinking and not categorical thinking. Language had to exist prior to that symbolic thinking or else we would likely see its precursors in the higher primates and that has yet to be demonstrated. Yes, chimps can categorize, but there is no evidence as yet that they deal in symbols or communicate in purely symbolic terms as we do routinely.
I would argue that the foundations of language need to be viewed in an evolutionary context. Being able to communicate information that aided in our survival propelled us to talk. It was angst and not awe that helped form our brains.
And I suspect it happened quite early in homo's evolution. Erectus was likely a sophisticated communicator to judge by recent discoveries that showed mastery of fire and ocean travel.

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