Grade 10

Polar bear and global warming
Responses to Change

What can change teach us?


Mass Extinctions

Source: National Geographic

Five mass extinctions—the die-off of a majority of species—have occurred in earth’s history. What causes these periodic extinctions? A sudden change in climate or atmosphere that living things can’t adapt quickly enough to survive. Find out what we know about these changes and what species were able to flourish in their wake.

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