Concept explainers
To review:
The reason due to which the reproductive isolation is partial rather than complete, assuming that the reproductive isolation in phlox is observed because of lethal combinations of incompatible alleles at several loci among the various strains.
Introduction:
In early years, the biologists collected sample of seeds of newly found species of phlox. They distributed these species in nurseries in Europe. These nurseries found more than 200 breeding strains of phlox. These strains differed in flower size, color, and growth of plant. The reproductive isolations were not seen initially but after some subsequent experiments, reproductive isolations were observed.
The incompatibility was seen when the strains were crossed and seed production was measured and compared. The biologists found that reproductive compatibility fell down to 15–60%. This decrease was found due to crossing of the strains, which were isolated.
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Life: The Science of Biology
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