The Swoop of the Magpie (revisited)

["Philip Veerman" <>]

Hi Geoffrey,

 

I suspect you are assuming that there is some adaptive benefit in this swooping behaviour and that the creatures possess some form of intellectual cause and effect reasoning. Neither needs to be correct and the latter is very unlikely to be correct. They could just be pumped for aggression for removing aerial predators and some get an excess of aggressive urges. Maybe aerial diurnal climbing marsupial predators were more common before and it is an old habit. I suspect the reason has as much more to do with sexual selection (females preferring males that are good territory defenders) or intraspecific territoriality (males that attack other things are better at removing rival males) as anything else. (But I don't have evidence either way.) There is little or no risk or adverse impact on the magpie for doing this swooping. the issue has been fully addressed in the book "Magpie Alert" by Darryl Jones. See my September 2002 review of this book in CBN:27(3):138-139.

 

Philip