Bird population crashes seem to correlate with the strange
13-year and 17-year cycles of periodical cicadas. Some researchers suggest that
the dissonant insects actually orchestrate the behavior of their predators
As the first day of spring approaches a scientific mystery
will soon return with a roar— the 2013 return of the east coast brood of
cicadas, or Brood II. Now a team of scientists hint they may have a solution as
to why this brood and its fellows bizarrely emerge only after lulls more than a
decade long—to control their surroundings in ways that may lead to crashes in
numbers of predatory birds.
Magicicada septendecim |
Periodical cicadas are
the longest-lived insects known. After childhoods spent underground living off
the juices of tree roots, broods of red-eyed
adults surface in
precise cycles— 13
years long in the southeastern U.S.
and 17 years long in the northeastern part of the country. Fifteen broods
are known to exist today on Earth, all native to North
America . Brood II is set to emerge this spring in New York State , Connecticut ,
Maryland , North Carolina ,
New Jersey , Pennsylvania
and Virginia
with choruses of males bent on wooing mates with their din. It remains an
enigma why these cicadas only emerge together in the adult stage every 13 or 17
years, as opposed to some other duration — other cicada species are not so
synchronized.
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