Question

In the monkeyflowers studied by Bradshaw and Schemske reproductive isolation results from:

A) gametic incompatibility between pollen and ovule
B) sterility of hybrid offspring
C) color preferences of hummingbirds and bees
D) asynchrony in time in which plants reach reproductive maturity

Answer 1

Reproductive isolation in the monkeyflowers studied by Bradshaw and Schemske results from color preferences of hummingbirds and bees, which is a prezygotic barrier due to different flower species attracting different pollinators.

Step-by-step explanation:

In the study of monkeyflowers by Bradshaw and Schemske, reproductive isolation results from color preferences of hummingbirds and bees. This is an example of a prezygotic barrier, where two species of flowers attract different pollinators, thus preventing interbreeding. This mechanism is different from gametic incompatibility, reproductive organ incompatibility, hybrid embryo inviability, or asynchrony in reproductive maturity times, which are other forms of reproductive isolation barriers.