Vocabulary Chapter 1: Lesson 3 Natural selection Adaptation Niche Competition Predation Predator Prey Symbiosis Mutualism Commensalism Parasitism Parasite host

Natural Selection The process by which organisms that are best adapted to their environment are most likely to survive and reproduce. Examples: birds that have adapted to eating (activity), black mice on volcanic ash

Adaptation An inherited behavior or physical characteristic that helps an organism survive and reproduce in its environment.

Niche The role an organism plays in its habitat Examples: producer, predator, how they reproduce, and physical conditions it needs to survive.

the struggle between organisms to survive Competition the struggle between organisms to survive Examples: for food, sunlight, nutrients, water, shelter, space

predation One organism kills another for food or nutrients

predator Organism that does the killing A: prey Apply: Too many predators decrease the population

Prey The organism that is killed A: Predator Apply: a decrease in prey will lead to decrease in predators

Symbiosis Any relationship in which two species live closely together and at least one of the species benefits. Examples: mutualism, commensalism, parasitism

Mutualism A relationship that both species benefits Example: stinging ants in an Acacia tree, oxpecker eat ticks on Impala’s ears, hummingbird and flower

Example: ray and fish, tree and some plants Commensalism A relationship that one species benefits and there is no effect on the other Example: ray and fish, tree and some plants

Parasitism A relationship that one species benefits and the other species is harmed Example: Mistletoe, cowbird and yellow warbler, fish lice, lice, ticks

The organism that benefits Parasite The organism that benefits Example: tick, mistletoe, cowbird, lice

host The organism that is harmed Example: yellow warbler, fish, people, tree