When two salamander species, the red-backed salamander and the valley-and-ridge salamander, occur without the other present, their jaw structures are identical, and they consume the same prey. However, when the two species co-occur, the red-backed salamander has a slower-closing, stronger jaw, while the valley-and-ridge salamander has a faster-closing, smaller jaw, and the two species consume prey of different sizes. Which of the following is suggested by these observations?

(a)Competitive exclusion (b) Preemptive competition (c)A trade-off between growing fast and competing well (d)Character displacement

The correct option is 'd'

This is the example of character displacement.

Explanation:

It occur when difference among similar species as their geographical distribution overlaps and accumulation takes place in a region where they co occur .

Character displacement stands from competitive exclusion principle which is also known as Gause's law which states that two competitive species must differ in their ecological niche when they are present in  a stable environment.

Character displacement means both reproductive character displacement and ecological character displacement.

the answer would be..

b. sucking

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