RE: harpymimids; more terror bird stuff

["Williams, Tim" <TiJaWi@agron.iastate.edu>]

Nick Longrich wrote:

> Screamers meanwhile are sort of avian ninjas, 
>with these inch-long bone daggers on the extensor process and smaller 
>ones at the end of the hand, keratinous sheaths made them even 
>longer. 

What's more, the "daggers" are detachable.  Screamers have been found with
the metacarpal spurs of other screamers lodged in their breasts!

>And spur-winged plovers are, well, self-explanatory. 

Jacanas and sheathbills also have wing spurs, and there might be other
spur-winged (or club-winged) birds I don't know about.  Interestingly, like
the spur- and club-winged anseriforms Nick mentioned, these birds are all
flighted (though their flight capabilities are modest by avian standards).
These birds take on the risk of damage to the flight feathers as a result of
these intraspecific confrontations.  To me, this is an argument in favor of
the first birds (and their immediate ancestors) using their wings for *both*
aerial flight and prey capture.  



Tim