Module 9S2 Changes in Populations

Lesson 2—Measuring Growth

Get Focused

White-tailed deer are browsers—they love the tender buds of shrubs and young trees that make up the transition area between fields and forest. Increasing deforestation due to urban sprawl and agriculture has opened up much more of this transitional habitat. In addition, natural predators of deer such as coyotes have been forced out of these areas by the same human activities. Hunting, which has been a traditional method of keeping white tail deer populations down, has fallen out of favor in modern times, with the taste for venison (deer meat) being met by domestic ‘deer farms’. With high food supply, and without predators, the size of white-tailed deer populations is large enough that in many areas of North America they are considered pests. In the state of Pennsylvania, more deer are killed by cars on the highway than die as a result of hunting.  An increasingly popular product is a device that sends out a high pitched sound from cars traveling rural roads, deterring deer from crossing roads, preventing vehicle/deer collisions. (Does this have an effect on gene flow?) Without competition and predation to weed out the sick and poorly adapted, the gene pool of white-tailed deer is becoming weaker, with a greater incidence of parasitism and contagious disease. With natality greater than mortality, the rate of growth continues to increase. With little selection of superior alleles, the gene pool is increasingly inferior to its previous state.

By the end of this lesson you should be able to answer the following focusing questions:

• How can data be analyzed to study population dynamics?
• What terms describe these population changes?

Module 9: Section 2—Lesson 2 Assignment

One you have completed all of the learning activities for this lesson, you can complete the online assignment.

Bio30 4.9.2S2 online assignment

You should also watch the tutorial video for this lesson and submit a summary.  Bio30 tut#4.9.2S2 Pop Density

In addition to your lesson work as listed below, any summary notes, sample problems, diagrams, charts or tables should be stored in the course folder for your teacher’s feedback and study as you prepare for exams.

You must decide what to do with the questions that are not marked by the teacher.

Remember that these questions provide you with the practice and feedback that you need to successfully complete this course. You should record the answers to all of the questions and place those answers in your course folder.