Question

Using our hypothetical "lizard island" example discussed in class, explain the classic 3-stage speciation process and how adaptation to local conditions can lead to speciation.

Answer 1

The classic 3-stage speciation process includes isolation, adaptation, and reproductive isolation. In the case of the lizards on the islands, the absence or presence of predators leads to different selection pressures and adaptations. Eventually, these differences can lead to speciation.

Step-by-step explanation:

Speciation is a process by which new species arise. In the classic 3-stage speciation process, isolation, adaptation, and reproductive isolation occur. In the case of the lizards on the two islands, the initial isolation due to the tsunami leads to different selection pressures. The island with no predators allows the lizards to evolve adaptations for defense, such as camouflaged coloration or toxins, while the island with a predator selects for traits that improve survival against the predator. Over time, these differences can accumulate and eventually lead to reproductive isolation between the two populations, resulting in speciation.