Unit 7: Topic 11 - Extinction

Question 1

How many mass extinctions have there been and what has been the root cause of such events?

Answer 1

There have been five major mass extinctions, and their causes are all from extreme environmental change.

Question 2

How is the rate of extinction influenced by ecological stress?

Answer 2

During times of ecological stress, extinction rates tend to be high due to species struggling to adapt to changing conditions.

Question 3

How can human actions harm ecosystems?

Answer 3

Human activities’ harmful effects on ecosystems include pollution and habitat destruction, which places organisms in abnormal conditions and can lead to species extinction.

Question 4

How does extinction and speciation affect the amount of biodiversity?

Answer 4

Speciation is directly proportional to biodiversity, which means as speciation increases, so does biodiversity. Extinction rates are inversely proportional to biodiversity, which means as extinction rates increase, biodiversity decreases

Question 5

How do extinctions provide new opportunities for species and allow for adaptive radiation?

Answer 5

When a species goes extinct, its niche (role) is available for other species to exploit. This can allow adaptive radiation to happen, which is the rapid evolution of a species to fill new niches since there are now multiple niches to fill.