Seasons occur because:

Seasons occur because:

Cattle egrets following cattle may actually represent:

Cattle egrets following cattle may actually represent:

Deserts receive:

Deserts receive:

Precipitation patterns depend on:

Precipitation patterns depend on:

Savanna seasons include:

Savanna seasons include:

Quantity over quality:

Quantity over quality:

Saltwater ecosystems include:

Saltwater ecosystems include:

Population stabilizes when:

Population stabilizes when:

Zero population growth:

Zero population growth:

An example of primary succession occurs after:

An example of primary succession occurs after: