Hi all

Is the peregrine falcon the fastest animal ever to live? If it is, are there currently any fossil animals that might have lived and hunted like a peregrine?

Although the peregrine is usually touted as the fastest animal, I think it's cheeting because it is gravity assisted.

In level, flapping, flight, the needle-tailed swift (Hirundapus caudacutus) is apparently the fastest animal, at 170km/h (http://en.wikipedia.org/wiki/White-throated_Needletail).

My knowledge of fossil animals is weak, I'm sure someone else will have some input on those soon.

>Although the peregrine is usually touted as the fastest animal, I think it's cheeting because it is gravity assisted.

Agreed - the swift wins and the falcon is clearly cheating. An interesting question though is what animal could beat a peregrine even with the assitance of gravity. Perhaps a (dead) mackerel thrown from a hot air balloon would reach a terminal velocity that beats a peregrines stooping velocity. Maybe a question for "ask a physicist" ?!?

I think this is a bit harsh on the old peregrine! Although a peregrine utilises gravity (cleverly, in my book, not just flapping along like some dumb swift... ;>)), they do not rely solely on gravity to reach their tremendous speeds (as noted above, they are gravity assisted).

Certainly, I would put large amounts of money on any mackerel (alive, or dead!) to reach a terminal velocity of about 128mph or so. A pergine can go so much faster because they fly with gravity (the difference between coasting down a hill on a bicycle and putting some real effort in to pedalling and streamlining oneself), before jamming on the 'air brakes' to take a great deal of the speed out of the stoop before hitting the target (sometimes!).

As with other closely related falcons, (saker, lanner etc.) the peregrine has special adaptations to enable basic functions (like seeing and breathing - the way that the fluting in the nostrils acts to slow air enough to make it breathable has been utilised by jet turbine engines (or at least, is the same 'design') to aid efficiency) at super-high speeds, not just your level flapping flight or 'mackerel-speed falling ', makes it, in my opinion, the fastest dang critter ever and, God bless it for being great. 

Note: I may like falcons. This has in no way coloured my view of this discussion {cough cough}...