The map shows the location of Earth's principal biomes. Tropic of
Cancer
Equator
Tropic of
Capricorn
Earth's principal biomes
Savanna Desert Chaparral
Tropical
forest
Temperate
forest
Tundra
Mountains
Polar ice
Boreal
forest
Temperate
grassland
Which abiotic factor in tropical forests do boreal forests lack?

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?