Animal flocks, be it honeybees, fish, ants or birds, often move
in surprising synchronicity and seemingly make unanimous
decisions at a moment's notice, a phenomenon which has remained
puzzling to many researchers. New research published today,
Wednesday 15 September, in New Journal of Physics, uses a
particle model to explain the collective decision making process
of flocks of birds landing on foraging flights. Using a simple
self-propelled particle (SPP) system, which sees the birds
represented by particles with such parameters as position and
velocity, the researchers from Budapest, Hungary, find that the
collective switching from the flying to the landing state
overrides the individual landing intentions of each bird. In the
absence of a decision making leader, the collective shift to
land is heavily influenced by perturbations the individual birds
are subject to, such as the birds' flying position within the
flock. This can be compared to an avalanche of piled up sand,
which would occur even for perfectl