Five closely related species of frogs live in ranges that overlap. Some breed in woodland ponds, some in lowland swamps, and some in streams. How do these five species of frogs remain separate and do not attempt to mate?

A line graph plots mating activity of 5 frog species over time, which ranges from March to July. The graph for each species is a bell-shaped curve. Each curve overlaps with 1 or 2 neighboring curves. From left to right, the curves are labeled wood frog, leopard frog, pickerel frog, green frog, and bullfrog.

Study the graph and the text to identify two modes of isolation.
A. Temporal isolation: The species remain separate because the period of most active mating differs.
B. Behavioral isolation: Each species has a courtship pattern that allows males and females to recognize each other.
C. Geographical isolation: The species remain separate because they have different breeding sites.
D. Reproductive isolation: The sperm of one species cannot fertilize the eggs from another species.

1 Answer

  • The answers are; geographical isolation and temporal isolation.

    In temporal isolation, because the different species have different mating seasons, so even though their habitats overlap, they do not interbreeding is rare. Geographical isolation also plays a role because the different species are found predominantly in different sites during breeding, some in the woodland, some in the lowlands and others in streams.