Pre-Lab: Competing For Resources
Problem How can competition lead to speciation?
Materials assorted tools, large and small seeds, large and small paper plates, timer or clock with second hand
Lab Manual Chapter 17 Lab
Skills Focus Use Models, Predict, Apply Concepts
Connect to the Speciation is not easy to see in nature. Usually, new phenotypes take years to emerge or become common enough to be noticed. Also, new phenotypes can be difficult to track in a complex environment. For scientists who want to study speciation, islands can provide an ideal environment.
Peter and Rosemary Grant spent years studying finches on the Galápagos Islands. They measured and recorded the traits and diets of hundreds of birds. During a year with a severe drought, the Grants were able to observe natural selection in action as food became scarce. In this lab you will model variation in bird beaks and diet to demonstrate the impact of competition on survival and speciation.
Review What is speciation?
Relate Cause and Effect How did geographic isolation lead to speciation among the Galápagos finches?
Compare and Contrast How does an adaptation differ from other inherited traits?
Preview the procedure in the lab manual.
Use Models In this lab, what do the different types of tools represent?
Predict Which tools do you think will work best for picking up small seeds? Which will work best for picking up large seeds?
Design an Experiment Why will the time you have to collect seeds be limited?
Visit Chapter 17 online to test yourself on chapter content and to find activities to help you learn.
Untamed Science Video Climb the cliffs of Hawaii with the Untamed Science crew to discover how geographic isolation can result in a new species.
Data Analysis Find out what happened to Galápagos finches during a drought by comparing data on finches and their food sources.
Art Review Review your understanding of alleles and allele frequencies in a population.
Art in Motion Watch how different types of selection change the types of individuals that comprise a population.
Tutor Tube Learn more about the mechanisms of speciation from the tutor.