Refer to the graph, which models the theory of island biogeography. The intersection points of the immigration and extinction curves on the graph represent points where, for that type of island,
A) immigration is overtaking extinction, and the species number is rising.
B) immigration and extinction are balanced, and the species number is in equilibrium.
C) immigration and extinction are balanced, and the species number can no longer change.
D) extinction is rising while immigration is declining, and the species number is declining.
E) extinction will begin to rise more rapidly on distant islands, while slowing on nearby islands.

Question

Refer to the graph, which models the theory of island biogeography.  The intersection points of the immigration and extinction curves on the graph represent points where, for that type of island,
A) immigration is overtaking extinction, and the species number is rising. 
B) immigration and extinction are balanced, and the species number is in equilibrium. 
C) immigration and extinction are balanced, and the species number can no longer change. 
D) extinction is rising while immigration is declining, and the species number is declining. 
E) extinction will begin to rise more rapidly on distant islands, while slowing on nearby islands.

Quizplus · Accepted Answer

The intersection points of the immigration and extinction curves on the graph represent points where immigration and extinction are balanced, and the species number is in equilibrium. This means that the number of species on the island is not increasing or decreasing significantly, but rather staying relatively constant.

Refer to the Graph, Which Models the Theory of Island