1) Research why elephant seals were almost extinct 100 years ago and how their near extinction resulted in a genetic bottleneck creating little genetic variation in the current population.
2) Reason that elephant seals are mammals, and like all mammals, their early mammalian ancestors were land dwellers.
3) Explore the adaptations required for a mammal to live in a marine environment. They will understand that adaptations are caused by genetic variation and environmental factors, and are not the result of choices made by the individuals.
Adapting for Other Grade Levels:This exercise can be modified for high school classes, or advanced middle school classes by requiring students to explain how an adaptation might become fixed in a population. This would involve mutation, and selection of the trait due to its adaptive advantage.
Materials and Resources:Equipment on Site for implementation of lesson:
Computer and digital projector or large-screen television.
Resources Listed Below can be found within the lesson:
Videos (Spanish and English)
Spanish Video:
Elefantes Marinos Serie Educacionales: Parte I Introduccion a los Elefantes Marinos ¿Quienes son los elefantes marinos?
QuickTime Movie version Windows Media Player version
English translation Video
Handouts: Pre and Post Assessment Sheet, Adaptation Worksheet
photos and diagrams
list of web links
Elephant Seal Genetic Bottleneck Information (http://evolution.berkeley.edu/evolibrary/article/bottlenecks_01)
Acknowledgements:This program is made possible through generous support and funding from the Friends of Santa Cruz State Parks and the California State Parks Foundation.