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Trends in social science

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More interesting graphs from GNXP, based on searches of JSTOR in the following journal categories: anthropology, economics, education, political science, psychology and sociology. Progress!

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Written by infoproc

October 1, 2008 at 3:22 pm

Darwin’s savages

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Somehow I don’t think he and Jared Diamond share the same view of indigenous peoples. From The Descent of Man:

The main conclusion arrived at in this work, namely that man is descended from some lowly organised form, will, I regret to think, be highly distasteful to many. But there can hardly be a doubt that we are descended from barbarians. The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind – such were our ancestors. These men were absolutely naked and bedaubed with paint, their long hair was tangled, their mouths frothed with excitement, and their expression was wild, startled, and distrustful. They possessed hardly any arts, and like wild animals lived on what they could catch; they had no government, and were merciless to every one not of their own small tribe. He who has seen a savage in his native land will not feel much shame, if forced to acknowledge that the blood of some more humble creature flows in his veins. For my own part I would as soon be descended from that heroic little monkey, who braved his dreaded enemy in order to save the life of his keeper, or from that old baboon, who descending from the mountains, carried away in triumph his young comrade from a crowd of astonished dogs – as from a savage who delights to torture his enemies, offers up bloody sacrifices, practises infanticide without remorse, treats his wives like slaves, knows no decency, and is haunted by the grossest superstitions.

Also, from Charles Darwin, A Naturalist’s Voyage Round the World, in which he describes Fuegians as

‘the most abject and miserable creatures I anywhere beheld’ and as existing ‘in a lower state of improvement than in any part of the world.’ … ‘These poor wretches were stunted in their growth, their hideous faces bedaubed with white paint, their skins filthy and greasy, their hair entangled, their voices discordant, and their gestures violent. Viewing such men, one can hardly make oneself believe that they are fellow creatures and inhabitants of the same world. It is a common subject of conjecture what pleasure in life some of the lower animals can enjoy; how much more reasonably the same question may be asked with respect to these barbarians. At night, five or six human beings, naked and scarcely protected from the wind and rain of this tempestuous climate, sleep on the wet ground coiled up like animals.’

Written by infoproc

June 20, 2008 at 11:56 pm

Darwin’s savages

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Somehow I don’t think he and Jared Diamond share the same view of indigenous peoples. From The Descent of Man:

The main conclusion arrived at in this work, namely that man is descended from some lowly organised form, will, I regret to think, be highly distasteful to many. But there can hardly be a doubt that we are descended from barbarians. The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind – such were our ancestors. These men were absolutely naked and bedaubed with paint, their long hair was tangled, their mouths frothed with excitement, and their expression was wild, startled, and distrustful. They possessed hardly any arts, and like wild animals lived on what they could catch; they had no government, and were merciless to every one not of their own small tribe. He who has seen a savage in his native land will not feel much shame, if forced to acknowledge that the blood of some more humble creature flows in his veins. For my own part I would as soon be descended from that heroic little monkey, who braved his dreaded enemy in order to save the life of his keeper, or from that old baboon, who descending from the mountains, carried away in triumph his young comrade from a crowd of astonished dogs – as from a savage who delights to torture his enemies, offers up bloody sacrifices, practises infanticide without remorse, treats his wives like slaves, knows no decency, and is haunted by the grossest superstitions.

Also, from Charles Darwin, A Naturalist’s Voyage Round the World, in which he describes Fuegians as

‘the most abject and miserable creatures I anywhere beheld’ and as existing ‘in a lower state of improvement than in any part of the world.’ … ‘These poor wretches were stunted in their growth, their hideous faces bedaubed with white paint, their skins filthy and greasy, their hair entangled, their voices discordant, and their gestures violent. Viewing such men, one can hardly make oneself believe that they are fellow creatures and inhabitants of the same world. It is a common subject of conjecture what pleasure in life some of the lower animals can enjoy; how much more reasonably the same question may be asked with respect to these barbarians. At night, five or six human beings, naked and scarcely protected from the wind and rain of this tempestuous climate, sleep on the wet ground coiled up like animals.’

Written by infoproc

June 20, 2008 at 11:56 pm

Darwin’s savages

leave a comment »

Somehow I don’t think he and Jared Diamond share the same view of indigenous peoples. From The Descent of Man:

The main conclusion arrived at in this work, namely that man is descended from some lowly organised form, will, I regret to think, be highly distasteful to many. But there can hardly be a doubt that we are descended from barbarians. The astonishment which I felt on first seeing a party of Fuegians on a wild and broken shore will never be forgotten by me, for the reflection at once rushed into my mind – such were our ancestors. These men were absolutely naked and bedaubed with paint, their long hair was tangled, their mouths frothed with excitement, and their expression was wild, startled, and distrustful. They possessed hardly any arts, and like wild animals lived on what they could catch; they had no government, and were merciless to every one not of their own small tribe. He who has seen a savage in his native land will not feel much shame, if forced to acknowledge that the blood of some more humble creature flows in his veins. For my own part I would as soon be descended from that heroic little monkey, who braved his dreaded enemy in order to save the life of his keeper, or from that old baboon, who descending from the mountains, carried away in triumph his young comrade from a crowd of astonished dogs – as from a savage who delights to torture his enemies, offers up bloody sacrifices, practises infanticide without remorse, treats his wives like slaves, knows no decency, and is haunted by the grossest superstitions.

Also, from Charles Darwin, A Naturalist’s Voyage Round the World, in which he describes Fuegians as

‘the most abject and miserable creatures I anywhere beheld’ and as existing ‘in a lower state of improvement than in any part of the world.’ … ‘These poor wretches were stunted in their growth, their hideous faces bedaubed with white paint, their skins filthy and greasy, their hair entangled, their voices discordant, and their gestures violent. Viewing such men, one can hardly make oneself believe that they are fellow creatures and inhabitants of the same world. It is a common subject of conjecture what pleasure in life some of the lower animals can enjoy; how much more reasonably the same question may be asked with respect to these barbarians. At night, five or six human beings, naked and scarcely protected from the wind and rain of this tempestuous climate, sleep on the wet ground coiled up like animals.’

Written by infoproc

June 20, 2008 at 11:56 pm

Brainpower ain’t free

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This NYTimes article describes research on the fitness costs and benefits of increased intelligence (learning ability). The specific results are for fruit flies, C. Elegans (worms) and E. Coli (bacteria), but the theoretical basis is well understood already. Evolutionary equilibrium occurs at a local fitness maximum, which means that further increases in brainpower come with negative fitness costs in some other area (e.g., disease resistance, physical capability). If brainpower could continue to increase without negative side effects, it would have. The fact that it hasn’t suggests that genes with beneficial effects on intelligence may also come with negative consequences.

Note that equilibrium is only an approximate condition — there may be directions in gene space in which overall fitness can still increase (even substantially), but it takes time for the random mutational process of evolution to find them. In most directions one would expect to find either only a very small positive (or zero) fitness gradient or a negative gradient, assuming a population that has been genotypically stable for a long time. Recent studies suggest that humans may have experienced rapid evolution in the last 10-50 thousand years due to the advent of agriculture, population growth, etc.

At the end of the article, one of the biologists seems ready to rediscover the Cochran-Harpending hypothesis 🙂 See also here.

NYTimes: … It takes just 15 generations under these conditions for the flies to become genetically programmed to learn better. At the beginning of the experiment, the flies take many hours to learn the difference between the normal and quinine-spiked jellies. The fast-learning strain of flies needs less than an hour.

But the flies pay a price for fast learning. Dr. Kawecki and his colleagues pitted smart fly larvae against a different strain of flies, mixing the insects and giving them a meager supply of yeast to see who would survive. The scientists then ran the same experiment, but with the ordinary relatives of the smart flies competing against the new strain. About half the smart flies survived; 80 percent of the ordinary flies did.

Reversing the experiment showed that being smart does not ensure survival. “We took some population of flies and kept them over 30 generations on really poor food so they adapted so they could develop better on it,” Dr. Kawecki said. “And then we asked what happened to the learning ability. It went down.”

The ability to learn does not just harm the flies in their youth, though. In a paper to be published in the journal Evolution, Dr. Kawecki and his colleagues report that their fast-learning flies live on average 15 percent shorter lives than flies that had not experienced selection on the quinine-spiked jelly. Flies that have undergone selection for long life were up to 40 percent worse at learning than ordinary flies.

… “Humans have gone to the extreme,” said Dr. Dukas, both in the ability of our species to learn and in the cost for that ability.

Humans’ oversize brains require 20 percent of all the calories burned at rest. A newborn’s brain is so big that it can create serious risks for mother and child at birth. Yet newborns know so little that they are entirely helpless. It takes many years for humans to learn enough to live on their own.

Dr. Kawecki says it is worth investigating whether humans also pay hidden costs for extreme learning. “We could speculate that some diseases are a byproduct of intelligence,” he said.

The benefits of learning must have been enormous for evolution to have overcome those costs, Dr. Kawecki argues. For many animals, learning mainly offers a benefit in finding food or a mate. But humans also live in complex societies where learning has benefits, as well.

“If you’re using your intelligence to outsmart your group, then there’s an arms race,” Dr. Kawecki said. “So there’s no absolute optimal level. You just have to be smarter than the others.”

Written by infoproc

May 6, 2008 at 11:52 am

Brainpower ain’t free

leave a comment »

This NYTimes article describes research on the fitness costs and benefits of increased intelligence (learning ability). The specific results are for fruit flies, C. Elegans (worms) and E. Coli (bacteria), but the theoretical basis is well understood already. Evolutionary equilibrium occurs at a local fitness maximum, which means that further increases in brainpower come with negative fitness costs in some other area (e.g., disease resistance, physical capability). If brainpower could continue to increase without negative side effects, it would have. The fact that it hasn’t suggests that genes with beneficial effects on intelligence may also come with negative consequences.

Note that equilibrium is only an approximate condition — there may be directions in gene space in which overall fitness can still increase (even substantially), but it takes time for the random mutational process of evolution to find them. In most directions one would expect to find either only a very small positive (or zero) fitness gradient or a negative gradient, assuming a population that has been genotypically stable for a long time. Recent studies suggest that humans may have experienced rapid evolution in the last 10-50 thousand years due to the advent of agriculture, population growth, etc.

At the end of the article, one of the biologists seems ready to rediscover the Cochran-Harpending hypothesis 🙂 See also here.

NYTimes: … It takes just 15 generations under these conditions for the flies to become genetically programmed to learn better. At the beginning of the experiment, the flies take many hours to learn the difference between the normal and quinine-spiked jellies. The fast-learning strain of flies needs less than an hour.

But the flies pay a price for fast learning. Dr. Kawecki and his colleagues pitted smart fly larvae against a different strain of flies, mixing the insects and giving them a meager supply of yeast to see who would survive. The scientists then ran the same experiment, but with the ordinary relatives of the smart flies competing against the new strain. About half the smart flies survived; 80 percent of the ordinary flies did.

Reversing the experiment showed that being smart does not ensure survival. “We took some population of flies and kept them over 30 generations on really poor food so they adapted so they could develop better on it,” Dr. Kawecki said. “And then we asked what happened to the learning ability. It went down.”

The ability to learn does not just harm the flies in their youth, though. In a paper to be published in the journal Evolution, Dr. Kawecki and his colleagues report that their fast-learning flies live on average 15 percent shorter lives than flies that had not experienced selection on the quinine-spiked jelly. Flies that have undergone selection for long life were up to 40 percent worse at learning than ordinary flies.

… “Humans have gone to the extreme,” said Dr. Dukas, both in the ability of our species to learn and in the cost for that ability.

Humans’ oversize brains require 20 percent of all the calories burned at rest. A newborn’s brain is so big that it can create serious risks for mother and child at birth. Yet newborns know so little that they are entirely helpless. It takes many years for humans to learn enough to live on their own.

Dr. Kawecki says it is worth investigating whether humans also pay hidden costs for extreme learning. “We could speculate that some diseases are a byproduct of intelligence,” he said.

The benefits of learning must have been enormous for evolution to have overcome those costs, Dr. Kawecki argues. For many animals, learning mainly offers a benefit in finding food or a mate. But humans also live in complex societies where learning has benefits, as well.

“If you’re using your intelligence to outsmart your group, then there’s an arms race,” Dr. Kawecki said. “So there’s no absolute optimal level. You just have to be smarter than the others.”

Written by infoproc

May 6, 2008 at 11:52 am

Brainpower ain’t free

leave a comment »

This NYTimes article describes research on the fitness costs and benefits of increased intelligence (learning ability). The specific results are for fruit flies, C. Elegans (worms) and E. Coli (bacteria), but the theoretical basis is well understood already. Evolutionary equilibrium occurs at a local fitness maximum, which means that further increases in brainpower come with negative fitness costs in some other area (e.g., disease resistance, physical capability). If brainpower could continue to increase without negative side effects, it would have. The fact that it hasn’t suggests that genes with beneficial effects on intelligence may also come with negative consequences.

Note that equilibrium is only an approximate condition — there may be directions in gene space in which overall fitness can still increase (even substantially), but it takes time for the random mutational process of evolution to find them. In most directions one would expect to find either only a very small positive (or zero) fitness gradient or a negative gradient, assuming a population that has been genotypically stable for a long time. Recent studies suggest that humans may have experienced rapid evolution in the last 10-50 thousand years due to the advent of agriculture, population growth, etc.

At the end of the article, one of the biologists seems ready to rediscover the Cochran-Harpending hypothesis 🙂 See also here.

NYTimes: … It takes just 15 generations under these conditions for the flies to become genetically programmed to learn better. At the beginning of the experiment, the flies take many hours to learn the difference between the normal and quinine-spiked jellies. The fast-learning strain of flies needs less than an hour.

But the flies pay a price for fast learning. Dr. Kawecki and his colleagues pitted smart fly larvae against a different strain of flies, mixing the insects and giving them a meager supply of yeast to see who would survive. The scientists then ran the same experiment, but with the ordinary relatives of the smart flies competing against the new strain. About half the smart flies survived; 80 percent of the ordinary flies did.

Reversing the experiment showed that being smart does not ensure survival. “We took some population of flies and kept them over 30 generations on really poor food so they adapted so they could develop better on it,” Dr. Kawecki said. “And then we asked what happened to the learning ability. It went down.”

The ability to learn does not just harm the flies in their youth, though. In a paper to be published in the journal Evolution, Dr. Kawecki and his colleagues report that their fast-learning flies live on average 15 percent shorter lives than flies that had not experienced selection on the quinine-spiked jelly. Flies that have undergone selection for long life were up to 40 percent worse at learning than ordinary flies.

… “Humans have gone to the extreme,” said Dr. Dukas, both in the ability of our species to learn and in the cost for that ability.

Humans’ oversize brains require 20 percent of all the calories burned at rest. A newborn’s brain is so big that it can create serious risks for mother and child at birth. Yet newborns know so little that they are entirely helpless. It takes many years for humans to learn enough to live on their own.

Dr. Kawecki says it is worth investigating whether humans also pay hidden costs for extreme learning. “We could speculate that some diseases are a byproduct of intelligence,” he said.

The benefits of learning must have been enormous for evolution to have overcome those costs, Dr. Kawecki argues. For many animals, learning mainly offers a benefit in finding food or a mate. But humans also live in complex societies where learning has benefits, as well.

“If you’re using your intelligence to outsmart your group, then there’s an arms race,” Dr. Kawecki said. “So there’s no absolute optimal level. You just have to be smarter than the others.”

Written by infoproc

May 6, 2008 at 11:52 am