Chapter 17, Problem 1AC

It is difficult to perform experiments that test hypotheses about how new species form. But what if people lived for a really long time? Design an experiment lasting 100,000 years to test whether allopatric separation leads to speciation. What would your study organism be? Why? What would you measure, how often would you measure it, and what would you expect to find if the allopatric speciation hypothesis is correct?

Summary Introduction

To design:

An experiment which lasts 100,000 years to test whether allopatric separation leads to speciation, and what would be the organism of study, and why that particular organism is chosen. Also, to determine how often experiment would be measured, and expectation related to finding if the allopatric speciation hypothesis is correct.

Introduction:

Speciation means the formation of a new species from the pre-existing ones. Allopatric speciation occurs when geographic isolation creates reproductive barrier among the individuals of the same population.

Explanation of Solution

Hypothesis: Allopatric speciation is correct.

Experimental animal: Drosophila, as it fulfills the conditions as an experimental animal, which must have a known genetic sequence and short lifespan of about 30 days.

Experiment: To test the hypothesis that the allopatric speciation is correct.

Method: Same species of Drosophila are collected from the same geographical environment, and divided into three groups: two experimental groups and one control group.

The two experiment groups are isolated in two different geographical areas, whereas the control group is kept in the same geographical environment.

Measure: The experiment is screened every 30 days in every new generation in order to obtain data about the traits gained and the traits eliminated in all three groups.

Analysis: Along the generations, each experimental group emerged with different characters and accumulated changes in genetic composition in comparison to the control group.

Finding: After 100, 000 years, along with the generations, the accumulated changes in both experimental groups lead to speciation.

Conclusion

Drosophila would be the study organism for allopatric speciation, as it has a very short lifespan and its genetic composition is known. The result of the experiment is measured after every generation.