Vocal Learning in Bird Brains

A new paper pushing the theory that the area of a birds brain that controls movement is the same region that controls singing and learning to sing. It is the first study to use Molecular Mapping to examine the areas of a birds forebrain that control movement. Erich Jarvis suggests that ‘spoken language areas evolved out of pre-existing motor pathways’. Perhaps it is one possible reason why humans gesture with their hands as they are speaking. It is believed that the common ancestor of reptiles, birds and mammals, Amnitoes, shared similar motor pathways.

Cerebral systems that control vocal learning in distantly related animals evolved as specializations of a pre-existing motor system inherited from their common ancestor that controls movement, and perhaps motor learning.

The results back up claims that gestural language came before spoken language. Even now children are seen to gesture before they learn how to talk. ‘Gesturing is something that goes along naturally with speech. The brain areas used for gesturing may have been co-opted and used for speech’ says Erich Jarvis.

You can view & download the paper “Molecular Mapping of Movement-Associated Areas in the Avian Brain: A Motor Theory for Vocal Learning Origin” from PLoS ONE webiste.

5+1 Weird Chemicals

In case you missed the stuff of dreams article in the New Scientist Technology Blog here’s a quick overview, with one addition.

  • Dilatants are fluids that get more solid under stress. There are videos of people running across it and even dancing! This video shows sound waves at 80Hz producing interesting shapes using Cornstarch.
  • Auxetic materials get thicker when stretched. Pull them in one direction and they expand in another. A video demonstration from Bolton University.
  • Superfluids are made by cooling Helium down to a couple of degrees above absolute zero and can flow endlessly without friction. This article has an audio example of nano-whistles as helium-4 is pushed through nanometer-sized holes.

    In the case of superfluids, a pressure difference across a tiny hole would cause a vibration in the superfluid at a frequency – the Josephson frequency – that increases as the pressure increases. The fact that the fluid oscillates back and forth through the hole rather than flows from the high-pressure side to the low-pressure side, as a normal liquid would, is one of the many weird aspects of quantum systems like superfluids.

  • Ferrofluids are made from nanoscale magnetic particles suspended in a liquid. Sachiko Kodama‘s Protrude Flow sculpture uses ferrorfluids with electromagnets.
  • Dry ice is Carbon Dioxide in its solidic form (frozen at -78.5 °C). A video showing patterns produced when dry ice is dropped into water.
  • Aerogel a low density solid, semi-transparent in appearance and feels like Styrofoam. Used by NASA to trap spacedust particles aboard the Stardust spacecraft.