Science, Vol 246, Issue 4933, 1032-1034
Copyright © 1989 by American Association for the Advancement of Science
Temperature and sperm incorporation in polyploid salamanders
JP Bogart,
RP Elinson,
and
LE Licht
Department of Zoology, College of Biological Science, University of Guelph, Ontario, Canada.
Although most animals reproduce sexually, a number of all-female groups exist. Triploid hybrid salamanders appear to maintain themselves by using a male's sperm to activate their eggs, after which the sperm nucleus is eliminated (gynogenesis). The incidence of sperm nuclear incorporation in eggs of these salamanders depends on temperature. Triploid offspring derived gynogenetically are more frequent at lower temperature, whereas tetraploid offspring derived sexually are far more frequent at higher temperatures. Temperature-dependent variability in sperm nuclear incorporation helps explain the variability in reproductive modes reported for hybrid salamanders.