Archive for September 2nd, 2011

The focus of this semester’s forum will be the evolution of human intelligence. For the first meeting of the semester, we read Chapter 2 from Jared Diamond’s book, “The Third Chimpanzee,” titled, “The Great Leap Forward.” In it, Diamond discusses human evolution since our split from chimpanzees and attempts to identify some of the components that make humans unique.

Our discussion began with an update on the current state of knowledge of recent human evolution. When the book was written, in 1991, it was generally thought that culture alone, not biology, has driven human evolution since the Neolithic Revolution, as 40,000 years could not be enough time for biological evolution to produce noticeable change. (Note that this was the opinion of anthropologists, but the broader evolutionary biology community did not agree, as such an idea was inconsistent with standard evolutionary thought.) Since then the biological evolutionary arguments have become stronger and now it is believed that human change is driven by a co-evolutionary feedback cycle between culture and biology. Some evidence of genetic and neurological change over the last 40,000 years has been proposed, but relating it directly to genetic change via evolutionary processes is difficult. A simple question was raised, “While a Cro-Magnon man may look physically like a modern human, could he learn to use a computer?” The answer to that question is not clear, but what is clear is that a time span as short as 40,000 years is definitely enough time for biological evolution to produce change and so the question of biological versus cultural evolution remains an open question.

Another correction to the 1991 literature is that we now have solid evidence for interbreeding between early Homo sapiens as they migrated out of Africa and Neanderthals present in Europe at the time. The bottom line is this: if you are of African descent, you share none of your genome with Neanderthals, however, if you are of non-African descent, approximately 2.5% of your DNA comes from Neanderthals.

The main undisputed message from the reading was that the Great Leap Forward really did appear abruptly, in terms of an explosion of complex art and tool use, however, the cause(s) of this abruptness are largely unknown.

As the discussion developed, we talked about the changes in brain size since humans split from chimpanzees. We were reminded to be careful about assuming progress as there is no true directionality in evolution. In fact, there have been periods of decreasing brain size and it would be misleading to assume that intelligence is purely a product of bigger and “better” brains.

The rest of our discussion was devoted to defining “intelligence” and deciding what aspects of the definitions we will talk about this semester.

Definition 1
“Sine Qua Non” Humanity. This latin phrase means “without which there is nothing.” And in our context, without intelligence, there is no humanity. This definition is a major motivator of this semesters topic, but doesn’t really get us anywhere in terms of defining “intelligence.”

Definition 2
Intelligence is a faculty of _________.
-Brain *
-Neocortex !*
-Whole body *
-Mind !*
-Group !*
-Self/Ego/Identity !
-Will !
-Executive function !*

Definition 3
Intelligence is a faculty for _________.
-Consciousness !*
-Agency (requires counterfactual) !
-Problem solving *
-Processing information *
-Reasoning (induction, deduction, intuition, dialectic) !*
-Logic *
-Memory *
-Learning *
-Skill Acquisition *
-Valuation *
-Abstraction *
-Empathy !*
-Theory of Mind !*
-Reflection *
-Prediction *
-Language !*
-Perception *
-Communication *
-Social Relation management !*
-Tool use *
-Sentience ! (*)
-Executive functioning !*
-Physical spatial awareness *

As we developed our lists, we gave special designation to those that are interesting (!) and those that are tractable (*). The items that are both interesting and tractable will form the bulk of our discussions this semester (highlighted in bold).

Post contributed by J.L.

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