endangered
threatened
extinct
2. Changes in an environment
are always natural
are caused by humans
can be natural or can be caused by humans
3. Some scientists think dinosuars became extinct
after a meteorite hit the Earth
because of human activity
because they evolved into birds
4. Scientists estimate that
over 1/5 of the species that once lived on Earth are now extinct
over 2/3 of the species that once lived on Earth are now extinct
over 1/2 of the species that once lived on Earth are now extinct
5. The West Indian manatee is an endangered species due to
a combination of natural and man-made causes
disease
an increase in water temperatures
Score = Correct answers:
