Multiple Choice
Extinctions have occurred since life originated.However,since humans have been on Earth,many extinctions have occurred as a result of human activities.Biologists are concerned about this trend in extinctions and human presence.Which of the following choices is correct about how biologists estimate rates of extinctions?
A) Biologists estimate the number of extinctions by conducting annual counts of the most critical flora and fauna and by using past extinctions as models.
B) Biologists estimate the number of extinctions by analyzing habitat loss and studying recorded extinction events.
C) Biologists estimate the number of extinctions by monitoring all populations for births and deaths.
D) Biologists estimate the number of extinctions by constant examination of the fossil record,especially deep marine sediments.
Correct Answer:
Verified
Correct Answer:
Verified
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