Development of a New Species
Development of a New Species
Objectives
In this lesson, students examine the mechanisms that can cause speciation. Students will:
- describe factors that may lead to the development of new species: isolating mechanisms, genetic drift, founder effect, and migration.
- sequence events that can lead to reproductive isolation of two populations.
- predict how natural selection and geographic isolation can lead to the formation of new species in an imaginary scenario.
Essential Questions
Vocabulary
- Species: A group of organisms that can breed with each other and produce fertile offspring.
- Speciation: Organisms that can breed and produce fertile offspring change enough to be considered separate species/populations.
- Gene Pool: Combined genetic information of all the members of a particular population.
- Reproductive Isolation: The members of two populations cannot breed and produce fertile offspring.
- Behavioral Isolation: Two populations are capable of interbreeding but they have different behaviors that prevent them from breeding.
- Geographic Isolation: Form of reproductive isolation in which two populations are separated physically by geographic barriers such as rivers, mountains, or bodies of water.
- Genetic Drift: Random change in allele frequencies that occurs in small populations.
- Founder Effect: Change in allele frequencies as a result of the migration of a small group in a population.
- Migration: Movement of animals from one place to another.
Duration
90 minutes/2 class periods
Prerequisite Skills
Prerequisite Skills haven't been entered into the lesson plan.
Materials
- Speciation: Ways That New Species Can Form–Teacher Version (S-B-9-2_Speciation-Teacher Version.doc)
- Sequencing Map: Geographic Isolation in Lizards–Teacher Version (S-B-9-2_Sequencing Map-Teacher Version.doc)
- computers with Internet access, optional
- Random Sampling and Genetic Drift (animation)
http://upload.wikimedia.org/wikipedia/commons/b/b6/Random_sampling_genetic_drift.gif
- Speciation Demonstration–Teacher Version (S-B-9-2_Speciation Demonstration-Teacher Version.doc)
Related Unit and Lesson Plans
Related Materials & Resources
The possible inclusion of commercial websites below is not an implied endorsement of their products, which are not free, and are not required for this lesson plan.
- Random Sampling and Genetic Drift (animation)
http://upload.wikimedia.org/wikipedia/commons/b/b6/Random_sampling_genetic_drift.gif
- Genetic Drift
http://en.wikipedia.org/wiki/Genetic_drift
- The Gene Pool and Speciation
www.biology-online.org/2/14_gene_pool.htm
- Evidence for Speciation
http://evolution.berkeley.edu/evosite/evo101/VC1fEvidenceSpeciation.shtml
- Classroom Activity: Candy Dish Selection. Earth: A Dynamic Structure
www.ucmp.berkeley.edu/education/dynamic/session3/sess3_variation3.htm
- Founder Effect (animation)
www.blackwellpublishing.com/ridley/a-z/Founder_effect_b.asp
Formative Assessment
Suggested Instructional Supports
Instructional Procedures
Related Instructional Videos
Note: Video playback may not work on all devices.
Instructional videos haven't been assigned to the lesson plan.
DRAFT 05/26/2011