Before you buy wood, make sure it comes from a “_____ forest,” a forest where trees are replanted.

• young

• sustainable

• old growth

• planned

Fishing has become so intensive and ​ (a)   that many marine populations are ​ (b)   . These species cannot recover ​ (c)   enough to ​ (d)   constant overfishing.

• efficient
• shrinking
• quickly
• survive
• slowly
• growing
• inefficient

Place the causes with the correct sources.

Groups:

(a) Increase carbon dioxide

,

(b) Increase methane

• decomposing waste in landfills

• factories burn fossil fuels

• increased livestock

• cars burn fossil fuels

Select all human factors that contributed to the decline in the number of Hawaii's bird species.

• birds were scared by all the new people

• birds had no defense from new cats and snakes

• overhunting by people

• increased volcanic eruptions

• chickens brought disease

Species of turtles lived 210 million years ago, at the same time as the ​ (a)   . A species under serious threat is the ​ (b)   . A major threat to marine life is ​ (c)   . Clear plastic floating in the water looks a lot like the leatherback’s favorite meal—​ (d)   - and they eat it . This is dangerous since it’s impossible to ​ (e)   .

• dinosaurs
• leatherback turtle
• plastic
• jellyfish
• digest
• cavemen
• anemones

Match the description to its human cause of extinction.

• Overharvesting

• Greenhouse gases are building up in Earth’s atmosphere and trap heat contributing to a worldwide rise in temperature

• Pollution

• People take too many fish from the sea or cut down to many acres of forests and permanently damage ecosystems

• Invasive Species

• When people cut down forests, build cities, or make roads, they destroy habitats

• Habitat Loss

• Acid rain, oil spills, poisons, and plastic trash are big problem for biodiversity

• Global Climate Change

• When species land in a new place and disrupt the ecosystem