Question

passage 6430
directions: use the following scenario to answer any questions that follow.
ddt was a common pesticide used in the united states in the 1950s and 1960s.
although it was tested in mice for safety by scientists who produced it, other
environmental scientists observed that the shells of many predator birds, such as eagles,
were becoming fragile and breaking before the chicks hatched. this was causing a
significant decrease in eagle populations.

• in 1972, ddt was banned from agricultural use in the united states. environmental scientists proposed that the ban would be a solution to help increase populations of organisms such as the eagles. which natural phenomena was the ban designed to reduce?

a. carrying capacity
b. succession
c. bioconcentration
d. biological magnification

Explanation:

Biological magnification is the process where the concentration of a toxic substance (like DDT) increases as it moves up the food chain. DDT accumulated in eagles, top predators, causing eggshell thinning and population decline. The ban targeted this phenomenon to let eagle populations recover. Carrying capacity refers to maximum sustainable population size, succession is ecosystem change over time, and bioconcentration is toxin buildup in a single organism, not across the food chain.

Answer:

D. biological magnification