Reproductive adult diapause (including
quiescence) in male insects has been
characterized by many different traits in
different species, but it should be defined as a
reversible state of inability of the male to
inseminate receptive females. Male reproductive
strategy is under selection pressure towards a
balance between maximum chances of fertilization
of the females' eggs and minimum waste of
energy, as well as minimum predation risk.
Therefore, in species with a female reproductive
diapause, male reproductive strategy must be
adapted to female diapause and diapause-related
female and male strategies must be coadapted. In
a previous review (Pener, 1992, Chronobiology
International, 9:102-113) three types of such
coadapted reproductive strategies were
recognized: (1). The female is receptive in the
early part of her diapause when copulation
occurs. The male dies shortly after mating and
the female stores the sperm to fertilize the
eggs that develop after female diapause is
terminated. (2). The female is receptive during
diapause; oocyte development is arrested, but
mating occurs and the stored sperm fertilizes
the eggs after female diapause is ended.
Reproductive diapause may not occur in the male,
or it may exist in a portion of the males, and
the actual situation in a species may reflect
some balance in sperm precedence in that
species. (3). The female is refractory during
diapause and the male exhibits reproductive
diapause. The diapause is controlled by similar
environmental cues and the same endocrine
mechanism in both sexes, but male diapause
usually terminates before female diapause.
Recent data in the literature indicate that
strategy no. 3 may be quite widespread and there
are intermediate cases between strategies no. 2
and no. 3. Moreover, some further strategies may
exist. Male diapause is under two antagonistic
selection pressure; a male should not waste
energy to court refractory females, but should
be ready to mate as soon as the female becomes
receptive.
Index terms: reproductive diapause, male,
coadaptations, environmental cues.
Copyright:
The copyrights of this original work belong
to the authors (see right-most box in title
table). This abstract appeared in Session 18
– REPRODUCTION AND DEVELOPMENT Symposium and
Poster Session, ABSTRACT BOOK II –
XXI-International Congress of Entomology,
Brazil, August 20-26, 2000.