Ch. 4 Lesson 3How do

environments change?

succession•gradual change in an ecosystem

•climates change slowly

succession

•occurs in

stages

extinct• species has completely died out

• caused by climate changes, volcanoes, meteors

extinction in modern times caused by human

activities-ex. habitat destruction

passenger pigeon

endangered• species that is reduced & may die out

• in danger of becoming extinct

There are only about 1,600 pandas left in the wild, and about 160 living in zoos.

Find the Endangered Animals game

black rhinoceros

threatened• species

may soon become endangered- just a step behind becoming endangered

giraffe

green sea turtle

extinct

endangered

threatened

fossils• show that Earth has changed

over time

• tell us about environment long ago

Fossils show that woolly

mammoths are similar to today’s _____________elephants

Factors that cause rapid

environmental changes :

hurricanes

fire

floods

volcanic eruptions