European scientists have determined birds with bigger brains tend to stay put in the winter and are more innovative in their feeding habits.
The journal Nature said Daniel Sol of the Independent University of Barcelona and his research team recorded observations on 134 European species to make their findings.
The researchers found birds wintering in Europe were less picky about what they eat and those observed using techniques to get at food in the winter had larger brains.
For example, the blackbird, Turdus merula, was spotted using twigs to clear snow away and the bullfinch, Pyrrhula pyrrhula, was observed scavenging from chicken and duck carcasses.
Non-migranting birds use an average of four innovative techniques, short-distance migrants three and long distance migrants one.
"Species with greater foraging flexibility seem to be able to cope with seasonal environments better, while less flexible species are forced to become migratory," Sol said.
Copyright 2005 by United Press International
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