Living Things in Ecosystems Chapter 2

Case Study Borneo – 1955 World Health Organization used DDT to kill malaria-carrying mosquitoes Also killed wasps Wasps eat local caterpillars Caterpillars ate thatch roofs DDT infected roaches were eaten by geckos Gave the geckos nerve damage  slow reflexes http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2636426/

Case Study Geckos eaten by house cats Cats ingested DDT and began to die Rats moved from forests to town Fleas live on rats The fleas carried the bacteria that cause the plague Healthy cats had to be parachuted into Borneo to deal with rat population

What is an Ecosystem? The dynamic and interrelating complex of plant and animal communities and their associated non-living environment Communities and their abiotic environment Examples? Have no distinct boundaries Ecotone Area where two ecosystems overlap Movement between ecosystems

What is an Ecosystem? Has both Biotic and Abiotic factors Biotic Living parts of an ecosystem Plants, animals, microorganisms Complex interactions between them Abiotic Non-living parts of an ecosystem Temperature, sunlight, humidity, water supply, soil type, mineral nutrients

Organization Organism Species Population One individual living thing Animal or plant Species A group of organisms that are able to reproduce together Individuals resemble one another Population Individuals of the same species living together in a particular place at a given time

Organization Community Ecosystem Biosphere A group of interacting populations All populations make up communities Land communities are dominated by plants Ecosystem Biosphere Areas of planet where life exists Composed of many ecosystems

Niche and Habitat Niche Habitat All of an organism’s relationships with its environment, both living and non-living Its “profession” Reproductive habits Active time of day Habitat The actual place that an organism lives Its “address”

Niches by Location

Coastal Niches

How Species Interact Symbiosis: https://www.youtube.com/watch?v=zSmL2F1t81Q Predation One organism kills and eats another Predator Prey Tends to have little effect on prey populations Predators eat whatever is abundant

How Species Interact Competition When species attempt to use the same limited resource Animal or plant Competing species don’t necessarily have to come in contact with one another Not always competing for food

How Species Interact Parasitism One organism benefits while the other is harmed Parasite Lives on or in another organism (the host) and feeds on it without immediately killing it Tends to weaken the host Vulnerable to predators

Parasites

How Species Interact Mutualism Commensalism A cooperative partnership between two species Both benefit, neither is harmed Commensalism One species benefits while the other is neither helped or harmed https://www.youtube.com/watch?v=RBR_w2-0LiQ https://www.youtube.com/watch?v=fkzUziLiiDM