Kinds of Organism Interactions Competition Principle of Competitive EXclusion: No two species can occupy the same ecological niche in the same place at the same time Less fit species must evolve into a slightly different niche
Kinds of Organism Interactions • Competition – Principle of Competitive Exclusion: No two species can occupy the same ecological niche in the same place at the same time. Less fit species must evolve into a slightly different niche
Competition: Several vultures competing for a food source Whenever a needed resource is in limited supply, organisms compete for it. This competition may be between members of the same species (intraspecific), or it may be between different species(interspecific
Competition: Several vultures competing for a food source. Whenever a needed resource is in limited supply, organisms compete for it. This competition may be between members of the same species (intraspecific), or it may be between different species (interspecific)
Symbiotic Relationships Symbiosis: Close, physical relationship between two different species. At least one species derives benefit from the interaction Parasitism: One organism(parasite) living in or on another organism(host), from which it derives nourishment Ectoparasites: Live on host's surface Fleas Endoparasites: Live inside host 令 Tapeworms
Symbiotic Relationships • Symbiosis: Close, physical relationship between two different species. At least one species derives benefit from the interaction. • Parasitism: One organism (parasite) living in or on another organism (host), from which it derives nourishment. – Ectoparasites: Live on host’s surface. Fleas – Endoparasites: Live inside host. Tapeworms
Parasitism Ectoparasites: Fleas are small insects that live in the feathers of birds or the fur of mammals where they bite their hosts to obtain blood Endoparasites: Tapeworms live nside the intestines of their hosts, where they absorb food from their hosts intestines
Ectoparasites: Fleas are small insects that live in the feathers of birds or the fur of mammals, where they bite their hosts to obtain blood. Parasitism Endoparasites: Tapeworms live inside the intestines of their hosts, where they absorb food from their hosts’ intestines
Symbiotic Relationships Commensalism: One organism benefits while the other is not affected. (Remoras and Sharks) Mutualism: Both species benefit -obligatory in many cases as neither can exist without the other.(Yuccas and Yucca Moths)
Symbiotic Relationships • Commensalism: One organism benefits while the other is not affected. (Remoras and Sharks) • Mutualism: Both species benefit – Obligatory in many cases as neither can exist without the other. (Yuccas and Yucca Moths)