Most birds build their own nests and incubate their own eggs. However,
some birds like the cuckoo have managed to get around this inconvenience
by simply laying their eggs in the nests of other species and letting
someone else do the hard work of keeping the eggs warm and protected
until the chick hatches. The ‘host’ (the poor sucker who ends up taking
care of the other birds’ eggs) does everything they can to try and make
sure the eggs that they’re sitting on are just their own. On the other
hand, the ‘brood parasite’ (the freeloader bird that just lays in the
nests of others) does everything they can to make their eggs
indiscernible from the eggs of their host.
Of course, neither host nor parasite is trying to achieve anything
consciously; their eggs are shaped by evolution and there is natural
selection both on the brood parasite to produce eggs that are very
similar to the host they are attempting to parasitize, and on the host
to be extra discerning in telling which eggs are their own.
Lees meer: Scientific American
dinsdag 14 mei 2013
Birds arrange eggs in their nests to better detect imposters
vrijdag 3 mei 2013
Behavior of Seabirds During Migration Revealed
The behaviour of seabirds during migration -- including
patterns of foraging, rest and flight -- has been revealed in new detail
using novel computational analyses and tracking technologies.
Using a new method called 'ethoinformatics', described as the
application of computational methods in the investigation of animal
behaviour, scientists have been able to analyse three years of migration
data gathered from miniature tracking devices attached to the small
seabird the Manx Shearwater (Puffinus puffinus).
Lees meer: ScienceDaily
Labels: Trek - migration
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