Re: juveniles faster than adults

["John R. Hutchinson" <jrhutch@rvc.ac.uk>]

Another note to add to this discussion-

The big problem is there are very few hard data on near-maximal speeds of
any species- there are reliable data for humans, greyhounds, racehorses,
elephants, some lizards and a few other tetrapods. And then a lot of very
dodgy anecdotes (sometimes used as data...). 

Add to this that we know even less about change of absolute speed across
ontogeny. And add the caveat that one must be clear whether one is looking
across the full age range (from birth to old age) or just during the rapid
growth stage up to adult mass (or roughly that in indeterminate growers).
The former is not very useful, usually, as you add in decline of performance
with senescence; it is not hard to accept that the elderly of most species
have poor performance.

All things considered, I find it hard to accept any basic principles about
how -absolute- maximal speed varies (or does not) ontogenetically in
tetrapods. There are a few case studies but not enough good data.

However this is a simple area for any interested researcher to contribute
to. All you need is a video camera, measuring tape and some knowledge of
locomotion (modern standards of methods; easily obtainable from reading
recent literature or talking w/an expert). That's all I've needed for some
of my work in this area. And it is easier than you might think to find
animals to work with, if you bother trying. If you do this with almost any
species, it's an easy publication and of much general interest. Go for it!

Best,
John H