Page 96 - BBC Wildlife Volume 36 #06
P. 96
Q&A
WHAT
IS IT?
These toes were Though we share
made for gripping.
many traits, humans
are exceptional among
Whether one moves with the nimble great apes in blushing
– and crying.
athleticism of squirrels and gibbons
or the slow assuredness of sloths Q GREAT APES
and chameleons, a firm grip is a
basic requirement for an arboreal Is it just humans that blush?
a:AnupShah/ animal. And few grips come firmer blood vessels in the facial skin at times uakari monkeys deploy their bright red
A
than that of a Parson’s chameleon.
Blushing is caused by the dilation of
This inhabitant of Madagascar’s
faces as signals of physiological health).
Chame eon:A ex Hyde/naturep .com; gor naturepl.com; Golden eagle: Luis Quinta/naturep .com chameleons. Its opposable digits – “the most peculiar and most human of all complex emotion that requires knowing
humid forests is the heaviest of all
of embarrassment. Darwin considered it
Moreover, embarrassment is a highly
three on one side, two on the other
expressions”, and it appears to be unique to
what others are thinking about you, which
– allow it to wrap its feet securely
ourselves. That’s at least partly because we
may well be beyond the ken of any other
around any branch. However much
are rare in having our facial skin exposed
species. It remains a mystery why evolution
it struggles, that tree isn’t going
should favour a signal that is effectively an
to the scrutiny of others (though bald
anywhere. Clambering through the
canopy is not the only thing Parson’s
that, after making a social faux pas, people
chameleons do very slowly – their admission of guilt, though there’s evidence
are regarded more sympathetically if they
eggs take two years to hatch after
blush. Stuart Blackman
laying. Stuart Blackman
Q RAPTORS
Why do golden eagles
vary their nesting sites?
A Most long-established If another young duo is
pairs of golden eagles use trying to establish territory
a range of different eyries. close by, this helps to
Some tend to alternate ensure the newcomers are
between two or three; aware that the ground is
others, particularly in areas already taken.
with suitable crags around Alternating nest sites
mature forestry, may have helps to minimise parasitic
many more. Disturbance burden, given that many
from a previous season parasites can overwinter
may force a pair to move to in our increasingly mild,
a different nest, particularly wet climate. Severe storms
if they have failed to rear leading to nest damage
Golden eagles have
numerous dwellings young. On occasion, an and partial collapse close to
to insure against eyrie may be occupied that the laying period may also
disturbance or is close to the boundary force a pair to relocate.
damage.
of a pair’s hunting area. Polly Pullar
96 BBC Wildlife June 2018
