You are studying speciation of gecko lizards. Which of the experimental set-ups below would allow you to most effectively test the hypothesis that the presence of different types of habitats in the same area allows sympatric speciation to occur in a population of gecko lizards?
A. Place 20 lizards in each of six different tanks that all contain branches placed at the same height to perch on.
B. Place 20 lizards in each of six different tanks - three tanks with only high branches to perch on and three tanks with only low branches to perch on.
C. Place 20 lizards in a tank with both high and low branches to perch on.
D. Place 20 lizards in each of six different tanks that all contain high branches to perch on and low branches to perch on.

D. Place 20 lizards in each of six different tanks that all contain high branches to perch on and low branches to perch on.

Explanation:

Sympatric speciation is a form of speciation that occurs when a new species become evolve from a surviving ancestor, in which both species habitat overlap in the same environment. Their habitats are different, but both are still occupying the same environment.

The best experimental set up that would allow us to effectively test the hypothesis that the presence of different types of habitats in the same area allows sympatric speciation to occur in a population of gecko is option D. Here, placing the 20 lizards in each of six different tanks would eliminate the possibility of obtaining results as a result of chance, hence the creation of multiple groups of lizard.

Also, what makes option D more preferable set up is that 2 different habitats have been created by the presence of high branches to perch on and low branches to perch on. This would eventual lead to sympatric speciation, as two species would eventually occupy different branches.