[LINK] On the unlikelihood of intelligent life

NancyLebovitz

"The Planet-of-the-Apes Hypothesis" Revisited --Will Intelligence be a Constant in the Universe?

If intelligence is good for every environment, we would see a trend in the encephalization quotient among all organisms as a function of time. The data does not show that. The evidence on Earth points to exactly the opposite conclusion. Earth had independent experiments in evolution thanks to continental drift. New Zealand, Madagascar, India, South America... half a dozen experiments over 10, 20, 50, even 100 million years of independent evolution did not produce anything that was more human-like than when it started. So it's a silly idea to think that species will evolve toward us.

"The Planet-of-the-Apes Hypothesis" Revisited --Will Intelligence be a Constant in the Universe?

If intelligence is good for every environment, we would see a trend in the encephalization quotient among all organisms as a function of time. The data does not show that. The evidence on Earth points to exactly the opposite conclusion. Earth had independent experiments in evolution thanks to continental drift. New Zealand, Madagascar, India, South America... half a dozen experiments over 10, 20, 50, even 100 million years of independent evolution did not produce anything that was more human-like than when it started. So it's a silly idea to think that species will evolve toward us.

Ants then. They are 6% brain, which easily trumps humans in terms of EQ.

The idea that there's no trend towards bigger brains seems stupid. Almost as stupid as the idea that we should expect of see such a trend in all organisms.

All modern organisms evolved from bacteria-like critters, with little nervous tissue. Of course there's a trend towards bigger brains. The only issue is why - and that seems pretty obvious too: brains pay.

A random walk away from no brain by a large number of lineages would also give you a constantly increasing upper bound on brain size.

1Nornagest13y

That doesn't fly either, I'm afraid. EQ is not a straight brain-to-body-mass ratio; the expected brain mass in the formula scales sublinearly against body mass, giving smaller animals a tendency to have proportionally larger brains. This is motivated by the fact that some nervous functions (diaphragm contraction, for example) are relatively constant in complexity but still have to be handled by small animals' brains, so the smaller an animal is the more nervous overhead it has to deal with. The formula this works from was only designed to apply to mammals; different body plans have different neural requirements, and arthropod nervous systems are very different from mammalian. If we ignore that and apply the mammalian formula Ew(brain) = 0.12w(body)^0.66 to something ant-sized, it gives us an expected brain mass of about three milligrams for an ant weighing four milligrams (obviously absurd, but we knew the formula was bogus) and an encephalization quotient of about 0.08 if your 6% value is accurate. Human EQ is about 7.5.

11

[LINK] On the unlikelihood of intelligent life

11

11

11

[LINK] On the unlikelihood of intelligent life

11

11