Posted by Dima DD on 20-02-2006 01:32
#24
LordV wrote:
New theory on this behaviour. ...Wonder if it's a way of warming up faster by letting the drop warm up in the sun and then sucking it back in again. Another reason for wondering this is normally flies seem to to sunbathe with their back to the sun (ie head away from the sun), whilst when they are bubble blowing they always seem to be facing the sun or at least at right angles to it, so the bubble is getting full sun.
Brian V.
I can not say which hypothesis is correct. However, I would like to put some words about
this branch. In fact, body of the fly is darker and absorbs much more radiation than shining droplet. Moreover, evaporation of water from the surface must decrease droplet temperature, not warm it. More intensive evaporation - less the droplet temperature. Therefore, according to
this branch of hypotheses ("thermoregulative"...), fly can use bubbling for cooling of its overheated body (i.e. it is some kind of "perspiration" ).
Edited by Dima DD on 20-02-2006 19:21