>Recipe For Energy Saving Unravelled In Migratory Birds
>ScienceDaily (May 13, 2008) — Pointed wings together with carrying
>less weight per wing area and avoidance of high winds and atmospheric
>turbulence save a bird loads of energy during migration. This has been
The wing shape and loading aspects are hardly new. Allen Keast
demonstrated these principles with Australian honeyeaters about 40
years ago! The known migrant and nomad species had longer and more
pointed wings than the sedentary or short-movement species (brutal
summary). From memory Pied, Black and Painted Honeyeaters had the
(relatively speaking) longest and pointiest wings - and they move
probably the longest distances of all the Australian honeyeaters.
Quote from abstract:
"... Wing morphology varies with extent of seasonal movements, a long
pointed wing characterizing Myzomela nigra, Certhionyx variegatus, and
Grantiella picta, whose movements extend the length of the continent.
Within Myzomela there are relative differences in wing-length between
species undertaking extensive, moderate, and no, seasonal movements.
In other genera, and in the case of regional populations within
species, slight to moderate differences are not, however, reflected in
changed wing-form. This could be because the meliphagid wing is
already proportioned for considerable mobility ..."
Ref:
Keast, A. (1968). Seasonal movements in the Australian honeyeaters
(Meliphagidae) and their ecological significance. Emu 67(3): 159 -
209.
--
++++++++++++
Lawrie Conole
28 Reid Street
Northcote, VIC 3070
AUSTRALIA
lconole[at]gmail.com
0419 588 993
==============================www.birding-aus.org
birding-aus.blogspot.com
To unsubscribe from this mailing list,
send the message:
unsubscribe
(in the body of the message, with no Subject line)
to:
=============================
|
