Chapter 22.3, Problem 3R

Summary Introduction

To review:

a. Plot the graph on the basis of given data.

b. Analyze whether the data and the hypothesis show consistency in describing that the speciation in the given group of birds is related to the isolation of populations on the island that is newly formed.

c. Determine whether the speciation by geographical isolation will continuously occur in Darwin’s finches when no new islands are created in the Galapagos archipelago.

Given:

It is given that in the past 3 million years, the species of Darwin’s finches have evolved on the islands of the Galapagos archipelago. The various speciation events are determined by the molecular clock analysis. The ages of the various Galapagos islands are determined by dating rock samples by geological techniques.

The table given below shows that, in the past 4 million years, the number of species of Darwin’s finches and the number of islands that existed in the archipelago at several times.

Introduction:

Darwin was the first scientist to study the species of finches, which were found in the islands of the Galapagos archipelago. These finches are one of the most famous examples of the allotropic speciation. The species differ from one another due to their environmental conditions. The various speciation events in phylogeny are determined by the molecular clock analysis. To determine the age of the various Galapagos islands, various geological techniques are applied.