A biologist conducted an experiment on two Islands (A and B) of similar size, climate, species composition, and richness. Originally, the same species of snake was present on
both islands in small
numbers. In her
experiment, the biologist removed the snake from
Island A but not from Island B. She then recorded the number of animal species on each
island over a period of 24 months. The data collected is shown in the graph below:
40
Number of Species
30
25
20
15
10
5
А
B
7 10 13 16 19 22
Time (months)
Analyze the data above in terms of interspecific relationships and communities. Which
statement best explains the difference in species present on each island over the course
of the experiment?
A. The snake was a keystone species
B. The snake was a foundation species
C island A needs the snake as an ecosystem engineer.
D. Island B lost diversity due to remaining snakes.