Unit 2: The Living World: Biodiversity

Species richness

_ refers to the number of different species found in an ecosystem

ecological service

A(n) _ is something that benefits humans, comes from a natural process and occurs in a healthy ecosystem.

diversity

Island is determined by size and the distance to the mainland and size.

Ecological tolerance

_ refers to the range of conditions that an organism can endure before injury or death.

changing

Organisms that reproduce quickly can adapt to environmental conditions.

keystone

A ___ species maintains an ecosystem and keeps it functioning in a sustainable way.

indicator species

A(n) ____ is a species that serves as early warnings that an ecosystem is changing.

Primary succession, secondary succession

_ begins in a lifeless area with only rock present, while ___ occurs in an area where soil is present.

pioneer

A(n) species (lichen) begins the process of soil formation.