THE SEX ISSUE
IT PAYS TO
DISPLAY
Before sex, of course, comes the courting period – and few know how to catch the eye quite like
birds. Males have evolved an array of dazzling displays designed to attract females, strengthen
pair bonds and prove they’re made of the right stuff to raise their would-be partner’s young
Alex Dale
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BIRDLIFE • JUNE 2017
THE EYES HAVE IT
INDIAN PEAFOWL Pavo cristatus
Photo Percom/Shutterstock
In most bird species, the males are the flamboyant sex,
and the females are the ones who do the choosing. This
arrangement has come about because the process of
producing eggs involves a great amount of energy on the
female’s part, so she is extra careful to ensure that these
efforts aren’t expended on a male who will produce weak
offspring. Females take the business of selecting a mate
seriously, scrutinising their calls and their plumage for any
JUNE 2017 • BIRDLIFE
IN MOST BIRD
SPECIES,
MALES ARE THE
FLAMBOYANT SEX
hints that can tell her about his strength, health or vigour –
traits, after all, that will be passed on to his young. Thus, to
maximise their chances of spreading their genes, in some
species the males have developed flashy courtship displays
to show off their charms in the best possible light, and woo
females away from their rivals. Traits preferred by the female
of the species are exaggerated over time. There is no better,
or more famous, illustration of the evolutionary cost of this
process for the male than of the peacock – encumbered,
thanks to many generations of sexual selection, with an
impossibly ornamental tail, which it flares in spectacular
fashion in its attempt to court a peahen.
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