The “tool use” theory of the origin of intelligence is widely discredited.
Neanderthal man was bigger than us, and had bigger brains. Extinction is too common to mean very much. Most species trend larger—until they get reset by meteorite strikes. I’m not aware of any partiularly noteworthy growth of primates. Our ancestors have mostly grown, if that’s what you mean.
CronoDAS brought up the tools, not I; but I would still like to see some references about it being ‘widely discredited’. Tool use seems like one of the most significant aspects of intelligence to me...
Neanderthal cranial capacity is often thought to have been as large or larger than modern humans, indicating that their brain size may have been the same or greater; however, a 1993 analysis of 118 hominid crania concluded that the cranial capacity of H.s. neandertal averaged 1,412 cc (86 cu in) while that of fossil modern H.s. sapiens averaged 1,487 cc (91 cu in).[6] On average, the height of Neanderthals was comparable to contemporaneous Homo sapiens.
That dates from 1993. Here’s some more recent material:
“Neanderthal brain size at birth was similar to that in recent Homo sapiens and most likely subject to similar obstetric constraints. Neanderthal brain growth rates during early infancy were higher, however. This pattern of growth resulted in
larger adult brain sizes but not in earlier completion of brain growth.”
Replied here but let’s move the discussion to this thread: quoting:
Yes, but they also had more massive bodies, possibly 30% more massive than modern humans. I’m not sure that they had a higher brain/body mass ratio than we do and even if they had, a difference on the order of 10% isn’t strong evidence when comparing intelligence between species.
If they did have significant additional brain mass, it’s possible it was was used to give them really good instincts instead of the more general purpose circuits we have.
This is a quote from Wikipedia supposedly paraphrasing Jordan, P. (2001) Neanderthal: Neanderthal Man and the Story of Human Origins. “Since the Neanderthals evidently never used watercraft, but prior and/or arguably more primitive editions of humanity did, there is argument that Neanderthals represent a highly specialized side branch of the human tree, relying more on physiological adaptation than psychological adaptation in daily life than “moderns”. Specialization has been seen before in other hominims, such as Paranthropus boisei which evidently was adapted to eat rough vegetation.”
If they did have significant additional brain mass, it’s possible it was was used to give them really good instincts instead of the more general purpose circuits we have.
It’s also possible that it did any of a hundred other things. Or that it didn’t strictly do anything itself, but was genetically tied to some other positively selected mutation. Or it was sexually selected. Or it arose without genetic change, from environmental factors, and there wasn’t enough time or pressure for natural selection to remove it again.
Why privilege this hypothesis? Other species that specialize in some way don’t usually grow big brains as a result. In any case the presence of any given physiological adaptation doesn’t imply the absence of intelligence. Modern human intelligence is powerful; any hominid species that happened to evolve it would have a very good chance of using it to spread rapidly. Evolution doesn’t say, “this species is used to relying on physical strength, if an intelligent member is born he just won’t rely on his intelligence”. Every animal is always struggling for survival, no matter how and how well adapted.
I’m not privileging the hypothesis, I’m speculating.
I didn’t mean to start an argument, but I think that you thought because I suggested a hypothesis, you assumed that I took it more seriously than other unspoken hypotheses.
The “tool use” theory of the origin of intelligence is widely discredited.
Neanderthal man was bigger than us, and had bigger brains. Extinction is too common to mean very much. Most species trend larger—until they get reset by meteorite strikes. I’m not aware of any partiularly noteworthy growth of primates. Our ancestors have mostly grown, if that’s what you mean.
CronoDAS brought up the tools, not I; but I would still like to see some references about it being ‘widely discredited’. Tool use seems like one of the most significant aspects of intelligence to me...
Mosst animals make very little use of tools. The (highly brainy) Cetaceans don’t seem to use them at all.
More important theories inculude the social brain hypothesis—and sexual selection.
Dolphins have been confirmed as tool-users. For example they are known to use sticks and kelp in mating displays and games.
Cool. An example:
http://news.nationalgeographic.com/news/2005/06/0607_050607_dolphin_tools.html
Neanderthal brains weren’t bigger than modern human. Wikipedia—Neanderthal
That dates from 1993. Here’s some more recent material:
“Neanderthal brain size at birth was similar to that in recent Homo sapiens and most likely subject to similar obstetric constraints. Neanderthal brain growth rates during early infancy were higher, however. This pattern of growth resulted in larger adult brain sizes but not in earlier completion of brain growth.”
http://pmid.us/18779579
Replied here but let’s move the discussion to this thread: quoting:
Yes, but they also had more massive bodies, possibly 30% more massive than modern humans. I’m not sure that they had a higher brain/body mass ratio than we do and even if they had, a difference on the order of 10% isn’t strong evidence when comparing intelligence between species.
If they did have significant additional brain mass, it’s possible it was was used to give them really good instincts instead of the more general purpose circuits we have.
This is a quote from Wikipedia supposedly paraphrasing Jordan, P. (2001) Neanderthal: Neanderthal Man and the Story of Human Origins. “Since the Neanderthals evidently never used watercraft, but prior and/or arguably more primitive editions of humanity did, there is argument that Neanderthals represent a highly specialized side branch of the human tree, relying more on physiological adaptation than psychological adaptation in daily life than “moderns”. Specialization has been seen before in other hominims, such as Paranthropus boisei which evidently was adapted to eat rough vegetation.”
It’s also possible that it did any of a hundred other things. Or that it didn’t strictly do anything itself, but was genetically tied to some other positively selected mutation. Or it was sexually selected. Or it arose without genetic change, from environmental factors, and there wasn’t enough time or pressure for natural selection to remove it again.
Why privilege this hypothesis? Other species that specialize in some way don’t usually grow big brains as a result. In any case the presence of any given physiological adaptation doesn’t imply the absence of intelligence. Modern human intelligence is powerful; any hominid species that happened to evolve it would have a very good chance of using it to spread rapidly. Evolution doesn’t say, “this species is used to relying on physical strength, if an intelligent member is born he just won’t rely on his intelligence”. Every animal is always struggling for survival, no matter how and how well adapted.
I’m not privileging the hypothesis, I’m speculating.
I didn’t mean to start an argument, but I think that you thought because I suggested a hypothesis, you assumed that I took it more seriously than other unspoken hypotheses.