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Researchers Unravel the Magic of Flocks of Starlings


Do fish swimming in schools or birds flying in flocks have a collective spirit that enables them to move as one? Are they animals with highly developed cognition, a complex instinct or a telepathic gift? A recent study conducted by the research group led by Prof. Charlotte Hemelrijk of the University of Groningen points in another direction. Mathematical models of self-organization show that complicated collective behaviour can be the consequence of a few simple behavioural rules.


In an article in the online journal PLoS ONE, Hemelrijk and scientific programmer Hanno Hildenbrandt use the StarDisplay computer model to describe the causes of the miraculous variety of shapes in flocks of starlings.


Schools of fish



Previously, Hemelrijk and her collaborators used a comparable computer model to investigate schools of fish. Observations in nature showed that these are always elongated. "Our models showed that the elongated shape of schools of fish were the automatic result of self-organization," Hemelrijk says. In addition to the usual grouping and coordination, no extra rules are needed to achieve this. A fish swimming behind another one will slow down to avoid bumping into the one ahead of it and its former neighbours then move inwards to fill the gap that has opened up. This results in an elongated school.


Fantastic variation



Flocks of starlings, however, produce a much richer variety of shapes. Video footage of flocks of starlings flying around in search of a place to roost show fantastic variation all over the world. Round, broad, elongated, flocks that shift shape from funnels to hourglasses, thickening, thinning; these are all existing variations. People have wondered for ages how all these different shapes are able to be created. In the 1930s, British ornithologist Edmund Selous -- also fascinated by flocks -- even attributed the tremendous variety to telepathy


Lees verder: http://www.sciencedaily.com/releases/2011/...10808083655.htm


Bron: University of Groningen