In-class Exercise: Sources of Variation in Populations
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This page first made public: Jun 16, 2009
Students identify sources of morphological variation (genetic, ontogenetic, sexual, and ecophenotypic differences) among the individuals of populations for three different species, one of which is colonial.
Skills and concepts that students must have mastered
How the activity is situated in the course
This project is offered the second week of the course and provides a basic foundation for students to know how to look at fossils to extract the morphological information they contain. Understanding sources of morphological variation in populations is considered foundational for all subsequent topics in the course.
Content/concepts goals for this activity
Understand the sources of morphological (and by extension, behavioral) variation among the individuals of a population and the role that such variation plays in adaptation and evolution.
Higher order thinking skills goals for this activity
Other skills goals for this activity
Description of the activity/assignment
To prepare for this in-class exercise, students read relevant background material in their textbook and then hear a lecture about sources of variation in populations. Students then form small groups (5 individuals per group) and spend time examining specimens sampled from natural populations of three species. They make sketches and discuss the different types of morphological variation seen, then assign different components of the observed varation to the following sources: Genetic, ontogentic, sexual and ecophenotypic.
Determining whether students have met the goals
Download teaching materials and tips
Activity Description/Assignment:In-class Exercise: Sources of Variation in Populations (Acrobat (PDF) 61kB Jun16 09)
- Instructors Notes:
- Solution Set:GLG 430 Lecture Variation in Populations (Acrobat (PDF) 2.3MB Jun16 09)