EXPLORATION OF HYBRIDIZATION AS A PROCESS OF SPECIATION
AMONG THE SPECIES
DROSOPHILA VIRILIS, D. MOJAVENSIS & D. PSEUDOOBSCURA

JILLYN COOK

Biology and Chemistry Department, Lake Superior State University,

Sault Ste. Marie, Michigan  49783, USA

	Abstract.  The possibility of hybridization as a factor of
speciation was explored by experimenting with three different
Drosophila species; D. virilis, D. mojavensis, and D.
pseudoobscura.  Data was collected January 11 through February
26, 1993.  Methods for care of the flies were adapted from
Carolina Drosophila Manual 1988.  Six different hybrid crosses
were attempted by using a no-choice method in order to restrict
reproductive isolation.  Objectives were to obtain F1 hybrids,
test them for fertility, and examine possible mechanisms for
success and failure.  No hybrids were obtained.  Several deaths
were caused by two types of mold; Rhizopus and Mucor.  Many of
the adults died without successful crossing.  Mechanisms for the
failure of this experiment were considered to be caused by
experimental error, for example, contamination; sexual selection
factors, such as courtship behaviors; and isolating mechanisms,
for instance, potential mates meet but do not mate.




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