Question

Many animals are in danger of extinction. One way to see the extent of the problem is to study the numbers of animals on the endangered species list. The following data show the numbers of endangered species for various groups of animals. The count is the total number of endangered species within the group. Thus, there are 37 mammals on the endangered species list within the United States and 249 others in the rest of the world.

Group	United States	Unites States and Foreign	Foreign Only
Mammals	37	19	249
Birds	57	16	153
Reptiles	8	8	64
Amphibians	6	0	8
Fishes	55	3	11
Snails	12	0	1
Clams	50	0	2
Crustaceans	10	0	0
Insects	13	2	4
Arachnids	3	0	0

a. If you wanted to summarize these data for the United States in a single number, what number do you think would be the most meaningful? Why?

b. If you wanted to summarize the situation for endangered mammals worldwide, including the United States, what number do you think would be the most meaningful? Why?

c. Does the average of the numbers in the United States column have a useful interpretation? Explain.

d. Write a paragraph summarizing the information in the data set. Make use of the summary numbers you chose in parts (a) and (b).

Answer 1