 Competition  Predation Symbiosis: * parasitism * mutualism *commensalism

 Intra specific competition – competition between the same species  Exploitation competition – competing species have roughly equal access to a specific resource but differ in how fast or efficiently they exploit it The faster you eat… the more you get!.

 Inter specific competition – occurs when parts of the fundamental niches of different species overlap. Interference competition – one species may limit another’s access to some resource Defend territory – release chemicals, chase away, stinging How Species Interact

Species must…. a. migrate to another area b. shift its feeding habits or behavior through natural selection and evolution c. become extinct in that area

1. Some plants displace others by having leaf and root systems that allow them to absorb more sunlight and soil nutrients than their competition. 2. Other plants produce chemicals that inhibit the growth or germination of seeds of competing species.

Two species that require the same resource cannot coexist indefinitely in an ecosystem in which there is not enough of that resource to meet the needs of both species.

 Fundamental niche: the potential ecological niche that an organism could have if there were no competition from other species.  Realized niche: the life style that an organism actually pursues because of competition from other species.

Resource Partitioning Character Displacement

 Ways to get lunch – pursuit, ambush  How to get away  Protective mechanisms – run fast, keen eye sight  Camouflage,  Chemical warfare  Warning coloration  Mimicry  Behavioral strategies  Protection from living in large groups

(d) Foul-tasting monarch butterfly (e) Poison dart frog Fig. 5-2, p. 103 Stepped Art (h) When touched, snake caterpillar changes shape to look like head of snake. (a) Span worm(b) Wandering leaf insect (c) Bombardier beetle (f) Viceroy butterfly mimics monarch butterfly (g) Hind wings of Io moth resemble eyes of a much larger animal.

Pathogen or infectious agent is a biological agent that causes disease or illness to its host. Predator: an animal that naturally preys on others.

Parasitism Mutualism Commensalism