4 ms·

Whenever someone asserts that mammalian-equivalent intelligence is incredibly unlikely to arise twice, I like to point towards very intelligent and social birds

by Udo 12y ago

Whenever someone asserts that mammalian-equivalent intelligence is incredibly unlikely to arise twice, I like to point towards very intelligent and social birds, like crows - who are capable of performing advanced mental feats without a neocortex.

metaphorm 12y ago
nature rarely does anything just once. if it can happen once it can almost certainly happen more than once, and almost certainly does happen more than once.
- Udo 12y ago
  In case it wasn't clear from my comment: that was my point. I agree with you.
Balgair 12y ago
Avian neuroscience is actually pretty cool. Our neocortex is made up of 6 layers of cell bodies, with interconnections and projections to other parts of the brain and body. The avian brain, however, is not divided into layers, but is more like the brainstem, in the sense that it's a lot of nuclei and bulbous areas called the nidopallium and mesopallium. The songbirds are well studied, if you want to do some research, as we the vocalizations are easier to measure and mess with. Mind that crows, though very smart for birds, as still nowhere near us humans or our close friends, the dog or pig. It still seems that the neocortex and many other factors have beaten the corvid brain to civilization and are, at least in this environment, better suited for higher intelligence. Good starter articles on corvid intelligence are: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626540/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626540/ http://academic.reed.edu/biology/professors/srenn/pages/teaching/web_2010/ndr_site/mechanism.html http://academic.reed.edu/biology/professors/srenn/pages/teac...
bshanks 12y ago
Tangentially, there is recent discussion of the idea that the neocortex is homologous to structures that do exist in the avian forebrain, eg that mammalian neocortex vs avian forebrain is almost the same processing units, wired with almost the same way connectivity, but just with a slightly different spatial organization: http://www.sciencedirect.com/science/article/pii/S096098221201322X http://www.sciencedirect.com/science/article/pii/S0960982212... Harvey J. Karten. Neocortical Evolution: Neuronal Circuits Arise Independently of Lamination. Some evidence is that some genes which correlate with cortical layers in mammals show up in these other places in avians.

by Udo 12y ago

metaphorm 12y ago

nature rarely does anything just once. if it can happen once it can almost certainly happen more than once, and almost certainly does happen more than once.

Udo 12y ago
In case it wasn't clear from my comment: that was my point. I agree with you.

Balgair 12y ago

Avian neuroscience is actually pretty cool. Our neocortex is made up of 6 layers of cell bodies, with interconnections and projections to other parts of the brain and body. The avian brain, however, is not divided into layers, but is more like the brainstem, in the sense that it's a lot of nuclei and bulbous areas called the nidopallium and mesopallium. The songbirds are well studied, if you want to do some research, as we the vocalizations are easier to measure and mess with. Mind that crows, though very smart for birds, as still nowhere near us humans or our close friends, the dog or pig. It still seems that the neocortex and many other factors have beaten the corvid brain to civilization and are, at least in this environment, better suited for higher intelligence. Good starter articles on corvid intelligence are: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626540/ http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626540/ http://academic.reed.edu/biology/professors/srenn/pages/teaching/web_2010/ndr_site/mechanism.html http://academic.reed.edu/biology/professors/srenn/pages/teac...

bshanks 12y ago

Tangentially, there is recent discussion of the idea that the neocortex is homologous to structures that do exist in the avian forebrain, eg that mammalian neocortex vs avian forebrain is almost the same processing units, wired with almost the same way connectivity, but just with a slightly different spatial organization: http://www.sciencedirect.com/science/article/pii/S096098221201322X http://www.sciencedirect.com/science/article/pii/S0960982212... Harvey J. Karten. Neocortical Evolution: Neuronal Circuits Arise Independently of Lamination. Some evidence is that some genes which correlate with cortical layers in mammals show up in these other places in avians.