Why do holidays exist? For the same reason as festivals, ceremonies, and souvenirs: To increase demand for hard-to-make stuff. This helps artisans at the cutting edge make a living. They are the innovators. Helping them advances technology. Our celebration of Independence Day, for example, creates demand for fireworks, firecrackers, and American flags.
I asked this question in a recent post. If you look at people sitting in an audience, about one-third of them will be touching their mouth.
I had wondered about this for years. Somehow blogging about it helped. A few days ago I was on the subway. Of the persons sitting, the usual fraction were touching their mouth. Nobody standing was touching their mouth with their hands but now and then I noticed them purse or lick their lips.
Which suggested an answer to my question: We get a small amount of pleasure from touching our mouths. The pleasure declines after it is “harvested” and takes several minutes to become available again. This mechanism evolved because it kept our lips moist. At the time it evolved, people spent little time sitting. The pleasure was obtained by pursing or licking your lips, which moistened them. Predictions: 1. if you watch people whose hands are busy, they will purse or lick their lips roughly as often as people in an audience touch their mouths. 2. The more you lick or purse your lips, the less you will touch them with your hands. 3. The more you touch your lips with your hands, the less you will purse or lick them.
Pagophagia (compulsive ice eating) is similar. It is caused by anemia (too little iron). In the Stone Age, there was no ice. An intense desire to crunch something in your mouth would have led you to crunch bones. Bone marrow is high in iron. It’s another mechanism that worked well in the Stone Age but now malfunctions (not that there’s anything wrong with touching your mouth with your hand). My self-experimentation is all about this sort of thing. It’s easy to sit, so we don’t sleep well. It’s easy to be inside in the morning, so we don’t sleep well. It’s easy to eat breakfast, so we don’t sleep well. it’s easy to avoid faces in the morning, so we get depressed. And so on.
More. Andrew Sullivan’s readers have other ideas: here and here. Thanks to Tyler Cowen.
In the journal In Character, Simon Baron-Cohen, the autism expert, writes:
Clinicians describe the deep, narrow interests in autism as “obsessions,” but a more positive description might be “areas of expertise.” Sometimes the area of expertise a person with autism focuses on appears not to be very useful (e.g., geometric shapes, or the texture of different woods). Sometimes the area of expertise is slightly more useful, though of limited interest to others (e.g., train timetables, or flags of the world). But sometimes the area of expertise can make a real social contribution (such as fixing machines, or solving mathematical problems, or debugging computer software).
My guess is that in autism, something is turned off that should be turned on. This allows the rest — in particular, the rest of what motivates us — to be seen more clearly. Everyone has a tendency toward expertise, says my theory of human evolution. Why everyone? Because everyone suffers from procrastination and the tendency toward expertise is the tendency that causes procrastination: It’s harder to do something new than to do what you did yesterday. Back in the Stone Age, this tendency toward expertise caused different people to do different hobbies, and become good at them. This was the beginning of occupational specialization.
Recently I visited some friends whom I hadn’t seen for a while. You’re more talkative, they said. I attribute this to flaxseed oil.
I became interested in the effects of flaxseed oil partly because of the aquatic ape hypothesis, the idea that living near water had a big effect on human evolution. During a long period of human prehistory, the theory says, we swam a lot, presumably to catch fish. If we ate lots of fish (high in omega-3) at the same time our brains grew large, it was quite possible that our brains need large amounts of omega-3 to function properly. Flaxseed oil is high in omega-3.
Elaine Morgan, the theory’s main proponent, has written several books about it, “each more po-faced [= academically correct] than the last,” she has said. I have finally read two of them and was pleased to find more scrutiny made the theory more plausible.
Background to the idea that humans were once aquatic is that several mammals have obviously become aquatic — starting on land they shifted to water. Sea lions, whales, and so on. Birds have become aquatic — for example, ducks. Insects have become aquatic. Elephants appear to have become aquatic and then terrestrial again — note how well they can swim. There is ample precedent, in other words.
Humans differ in all sorts of anatomical and physiological ways from other primates and the aquatic ape theory has straightforward explanations for many of them:
1. Humans have subcutaneous fat, other primates don’t. Other aquatic mammals do. Explanation: The fat serves as insulation.
2. Humans have almost no fur, other primates do. Other aquatic mammals don’t. Explanation: Fur creates drag in the water. In the air, fur insulates.
3. Humans are bipedal. Explanation: Walking upright keeps the head out of the water, allowing breathing.
In 2004, anthropologists discovered fossils of tiny human ancestors on an Indonesian island. Called micropygmies, they were about three feet tall. Their brains were smaller than chimpanzee brains. They appeared to be descended from Hmo erectus rather than Homo sapiens.
They survived until about 20,000 years ago — which was impressive, since Homo sapiens reached nearby islands about 50,000 years ago. Why didn’t the Homo sapiens kill off the micropygmies? Jared Diamond was puzzled by this:
The discoverers of the Flores micropygmies conclude that they survived on Flores until at least 18,000 years ago (1, 2). To me, that is the most astonishing finding, even more astonishing than the micropygmies’ existence. We know that full-sized H. sapiens reached Australia and New Guinea through Indonesia by 46,000 years ago, that most of the large mammals of Australia then promptly went extinct (probably in part exterminated by H. sapiens), and that the first arrival of behaviorally modern H. sapiens on all other islands and continents in the world was accompanied by similar waves of extinction/extermination. We also know that humans have exterminated competing humans even more assiduously than they have exterminated large nonhuman mammals. How could the micropygmies have survived the onslaught of H. sapiens?
One could perhaps seek a parallel in the peaceful modern coexistence of full-sized sapiens and pygmy sapiens in the Congo and Philippines, based on complementary economies, with pygmy hunter-gatherers trading forest products to full-sized sapiens farmers. But full-sized sapiens hunter-gatherers 18,000 years ago would have been much too similar economically to micropygmy hunter-gatherers to permit coexistence based on complementary economies and trade. One could also invoke the continued coexistence of chimpanzees and humans in Africa, based on chimps being economically too different from us to compete (very doubtful for micropygmies), and on chimps being too dangerous to be worth hunting (probably true for micropygmies). Then, one could point to the reported survival of the pygmy stegodont elephants on Flores until 12,000 years ago (1, 2): If stegodonts survived so long in the presence of H. sapiens, why not micropygmies as well? Finally, one might suggest that all of the recent dates for stegodonts and micropygmies on Flores are in error [despite the evidence presented in (1) and (2)], and that both stegodonts and micropygmies became extinct 46,000 years ago within a century of H. sapiens‘ arrival on Flores. All of these analogies and suggestions strike me as implausible: I just can’t conceive of a long temporal overlap of sapiens and erectus, and I am reluctant to believe that all of the dates in (1) and (2) are wrong. Hence I don’t know what to make of the reported coexistence.
Yes, I know, when you have a hammer everything looks like a nail. But I think Diamond is quite wrong about the nature of Homo sapiens economies 50,000 years ago. To Diamond, the big change was the invention of agriculture. Before that, hunter-gatherer; after that, farmer and occupational specialization. I believe there were vast economic changes long before agriculture — it took a long time to evolve language, and that didn’t start until there was already plenty of trading. By 50,000 years ago, I’m sure there was lots of specialization (Person A makes/knows X, Person B makes/knows Y), giving the Homo sapiens all sorts of tools and other useful expertise that the micropygmies didn’t have. They both hunted and gathered but much larger brains and a vast amount of expertise would have been for naught if they didn’t hunt and gather different foods. Homo erectus did not have anything like human language, as far as I can tell; therefore they didn’t have lots of trading or expertise. The two groups could co-exist because their foods were different. I suspect the H. sapiens, able to hunt really large animals, thought small animals, which supported the micropygmies, a waste of time.
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