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Ants Can Do It, Too!



... so how hard can it really be for a vertebrate?

  In tomorrow's _Nature_, controlled descent (almost parachuting, without
the parachute) in an insect demonstrates dynamic aerial three-dimensional
spatial organization in the cortex of the ant-brain (I mean, how else can
it judge aerial distances?)

  Yankoviak, S. P., R. Dudley, M. Kaspari. 2005. Directed aerial descent
in
  canopy ants. _Nature_ 433:624-626.

Abstract:
  "Numerous non-flying arboreal vertebrates use controlled descent (either
   parachuting or gliding sensu stricto) to avoid predation or to locate
   resources, and directional control during a jump or fall is thought to 

   be an important stage in the evolution of flight. Here we show that
   workers of the neotropical ant *Cephalotes atratus* L. (Hymenoptera:
   Formicidae) use directed aerial descent to return to their home tree
   trunk with >80% success during a fall. Videotaped falls reveal that *C.
   atratus* workers descend abdomen-first through steep glide trajectories
   at relatively high velocities; a field experiment shows that falling
   ants use visual cues to locate tree trunks before they hit the forest
   floor. Smaller workers of *C. atratus*, and smaller species of
   *Cephalotes* more generally, regain contact with their associated tree
   trunk over shorter vertical distances than do larger workers. Surveys
of
   common arboreal ants suggest that directed descent occurs in most
   species of the tribe Cephalotini and arboreal Pseudomyrmecinae, but not
   in arboreal ponerimorphs or Dolichoderinae. This is the first study to
   document the mechanics and ecological relevance of this form of
   locomotion in the Earth's most diverse lineage, the insects."

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


                
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