OpEdの楽しみ

ニューヨークタイムズ、フィナンシャルタイムズ、ウォールストリートジャーナル、ワシントンポストなどのOpEdを読む楽しみの一つは、第一線の研究者や政治家などが寄稿することでしょう。社会生物学の研究者として一般向けの本も書いているエドワード・ウィルソンがニューヨークタイムズに寄稿していました。TEDでも講演しているほどの、いや、TEDなんかで講演しなくても有名な方ですね。

THE STONE February 24, 2013, 7:30 pm312 Comments
The Riddle of the Human Species
By EDWARD O. WILSON

To begin, biologists have found that the biological origin of advanced social behavior in humans was similar to that occurring elsewhere in the animal kingdom. Using comparative studies of thousands of animal species, from insects to mammals, they have concluded that the most complex societies have arisen through eusociality — roughly, “true” social condition. The members of a eusocial group cooperatively rear the young across multiple generations. They also divide labor through the surrender by some members of at least some of their personal reproduction in a way that increases the “reproductive success” (lifetime reproduction) of other members.

Eusociality stands out as an oddity in a couple of ways. One is its extreme rarity. Out of hundreds of thousands of evolving lines of animals on the land during the past 400 million years, the condition, so far as we can determine, has arisen only about two dozen times. This is likely to be an underestimate, due to sampling error. Nevertheless, we can be certain that the number of originations was very small.

彼が提唱する言葉eusocialityは昨年出した本でも触れられていたようです。



昨年本が出るころにニューズウィークに寄稿していたものがあります。個人的にはこちらの方が、比較的ポップで読みやすかったです。Eusocialityについて説明しあるところを抜粋します。NYTでピンとこなかった方は読み比べるといいかもしれません。

Biologist E.O. Wilson on Why Humans, Like Ants, Need a Tribe
Apr 2, 2012 1:15 AM EDT
Religion. Sports. War. Biologist E.O. Wilson says our drive to join a group—and to fight for it—is what makes us human.

The drive to join is deeply ingrained, a result of a complicated evolution that has led our species to a condition that biologists call eusociality. “Eu-,” of course, is a prefix meaning pleasant or good: euphony is something that sounds wonderful; eugenics is the attempt to improve the gene pool. And the eusocial group contains multiple generations whose members perform altruistic acts, sometimes against their own personal interests, to benefit their group. Eusociality is an outgrowth of a new way of understanding evolution, which blends traditionally popular individual selection (based on individuals competing against each other) with group selection (based on competition among groups). Individual selection tends to favor selfish behavior. Group selection favors altruistic behavior and is responsible for the origin of the most advanced level of social behavior, that attained by ants, bees, termites—and humans.
Among eusocial insects, the impulse to support the group at the expense of the individual is largely instinctual. But to play the game the human way required a complicated mix of closely calibrated altruism, cooperation, competition, domination, reciprocity, defection, and deceit. Humans had to feel empathy for others, to measure the emotions of friend and enemy alike, to judge the intentions of all of them, and to plan a strategy for personal social interactions.

As a result, the human brain became simultaneously highly intelligent and intensely social. It had to build mental scenarios of personal relationships rapidly, both short term and long term. Its memories had to travel far into the past to summon old scenarios and far into the future to imagine the consequences of every relationship. Ruling on the alternative plans of action were the amygdala and other emotion-controlling centers of the brain and autonomic nervous system. Thus was born the human condition, selfish at one time, selfless at another, and the two impulses often conflicted.

NYTに戻りますが、人間が社会や集団で生きることになると、individual selection とgroup selectionの二つが重要になってくるそうです。ざっくりまとめると、集団の中で優れた個人となることと、集団内で助け合って優れた集団になるということで、利己的であると同時に利他的であるという、一見すると相反するものが同時に求められるというのです。

The second, more recently argued theory (full disclosure: I am one of the modern version’s authors), the grandmaster is multilevel selection. This formulation recognizes two levels at which natural selection operates: individual selection based on competition and cooperation among members of the same group, and group selection, which arises from competition and cooperation between groups. Multilevel selection is gaining in favor among evolutionary biologists because of a recent mathematical proof that kin selection can arise only under special conditions that demonstrably do not exist, and the better fit of multilevel selection to all of the two dozen known animal cases of eusocial evolution.

The roles of both individual and group selection are indelibly stamped (to borrow a phrase from Charles Darwin) upon our social behavior. As expected, we are intensely interested in the minutiae of behavior of those around us. Gossip is a prevailing subject of conversation, everywhere from hunter-gatherer campsites to royal courts. The mind is a kaleidoscopically shifting map of others, each of whom is drawn emotionally in shades of trust, love, hatred, suspicion, admiration, envy and sociability. We are compulsively driven to create and belong to groups, variously nested, overlapping or separate, and large or small. Almost all groups compete with those of similar kind in some manner or other. We tend to think of our own as superior, and we find our identity within them.

自分としてはビッグデータだとか、ロボットだとか語っていましたが、人間性というは人間が文明を持つ前からあり、生物や植物を含めた生態系の中から生まれたものであることを改めて思い起こしました。これだけ機械化された社会の中で、唯一残された自然があるとすれば人間そのものかもしれませんね。