Lesson 1.1 - Changing Populations

When you looked at the picture of Calgary in 1884, you must have thought how small the human population must have been.  The population of Calgary in 1884 was 506 people!  The estimated population today is over 1 million.  That is a population explosion!  How do scientists define a population? 

Read Changing Populations on page 256 in your textbook. Then, answer the following questions.

 

Question 1. What is the scientific definition of population?

Question 2. What three pieces of information are required to identify a population?

Question 3. When is a population considered to be at risk?

Question 4. How would you tell if a population is healthy?

 

Check your answers with those that follow.

 

 

 

 

 

 

 

 

 

 

 

 

Answers to Questions:

Question 1. What is the scientific definition of population?

The term population is a group of individuals of the same species living together in the same place at the same time.

Question 2. What three pieces of information are required to identify a population?

The three pieces of information required to identify a population are the species, the place, and the time.

Question 3. When is a population considered to be at risk?

A population is considered to be at risk when the rate of decrease is large.  This can be misleading because the numbers may still be excessive.  For example, a locust plague may have a large rate of decrease, but it would hardly be considered a population at risk.

Question 4. How would you tell if a population is healthy?

A population is considered healthy if it is increasing.  It is considered to be not healthy if the population is decreasing.


Go to the next page to continue Lesson 1.

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