Ecology - study of the interactions between living things and their surroundings.

Levels of Organization Biosphere Ecosystem Community Population Organism

Biosphere The portion of earth that supports life Extends from the lower atmosphere to the bottom of oceans Supports diverse array of organisms and wide range of climates

An ecosystem/biome - all of the living and nonliving things in a given area (climate, soil, water, rocks). Ecosystem Community Population Organism

Earth has six major biomes.

Community All the different species that live in the same place at the same time. Example Forest community Flowers, bushes, trees, snakes, frogs, birds, squirrels, deer, etc…

Population A group of one species, which interbreed and live in the same place at the same time. Example Population of bullfrogs in Jackson Bog

An organism - individual living thing ex: alligator.

13.2 Biotic and Abiotic Factors KEY CONCEPT Every ecosystem includes both living and nonliving factors.

13.2 Biotic and Abiotic Factors Abiotic factors are nonliving things. moisture temperature wind sunlight Soil Not constant (always changing) moisture sunlight

13.2 Biotic and Abiotic Factors Living components of the environment

13.2 Biotic and Abiotic Factors A keystone species is a species that has an unusually large effect on its ecosystem.

16.3 Water Quality 13.2 Biotic and Abiotic Factors Indicator species provide a sign of an ecosystem’s health. amphibians top predators

Producers provide energy for other organisms in an ecosystem. 13.3 Energy in Ecosystems Producers provide energy for other organisms in an ecosystem. Autotrophs - make their own food.

Almost all producers obtain energy from sunlight. 13.3 Energy in Ecosystems Almost all producers obtain energy from sunlight. Photosynthesis Chemosynthesis – produce energy from chemicals

Measuring productivity 13.3 Energy in Ecosystems Measuring productivity Gross primary productivity – rate at which producers capture E Biomass – organic material in an ecosystem Only E stored as biomass is available to other organisms in the ecosystem

13.3 Energy in Ecosystems Consumers are organisms that get their energy by eating other living or once-living resources. Heterotrophs

13.4 Food Chains and Food Webs Herbivores – eat producers Carnivores – eat other consumers Omnivores – eat both producers and consumers Detritivores – feed on the “garbage” of an ecosystem

13.4 Food Chains and Food Webs A food chain is a model that shows a single chain of consumers within an ecosystem. Arrows point in the direction that energy flows DESERT COTTONTAIL GRAMA GRASS HARRIS’S HAWK

A food web - interrelated food chains in an ecosystem 13.4 Food Chains and Food Webs A food web - interrelated food chains in an ecosystem

13.4 Food Chains and Food Webs Energy Flow Trophic level – indicates the organism’s position in the sequence of energy transfers Producers – 1st trophic level Herbivores – 2nd trophic level Predators of herbivores – 3rd trophic level

Quantity of Energy Transfers 13.4 Food Chains and Food Webs Quantity of Energy Transfers 10% of the total E consumed in one trophic level is incorporated into the organism in the next level E is used to maintain body T, to move, etc. E is lost when organisms escape being eaten decomposer return their E to the lower trophic levels E is lost in parts of the organism that can not be broken down by the predator bones, teeth, hair

13.4 Food Chains and Food Webs An energy pyramid shows the distribution of energy among trophic levels. Higher trophic levels contain less energy Support fewer individuals

Biomagnification - accumulation of toxins in the food chain. 16.3 Water Quality 13.4 Food Chains and Food Webs Biomagnification - accumulation of toxins in the food chain. Pollutants move up the food chain. Predators eat contaminated prey Top consumers are most affected. EX: DDT- Birds of prey

13.4 Food Chains and Food Webs Species Interactions Predation Predator – captures, kills, and consumes prey Influences where and how species live by determining their relationship in the food web Regulates population size Natural selection favors adaptations that improve the efficiency of predators at finding, capturing, and consuming prey Natural selection favors adaptations for prey to avoid, escape, or otherwise ward off predators

13.4 Food Chains and Food Webs

13.4 Food Chains and Food Webs Natural selection of plants has favored adaptations that protect them from being eaten Thorns, sticky hairs, tough leaves Chemical defenses (secondary compounds) Strychnine, nicotine, poison ivy May also have medicinal uses – codeine, morphine

13.4 Food Chains and Food Webs Parasitism – one individual is harmed (host) while the other benefits (parasite) Does not usually result in the immediate death of the host

13.4 Food Chains and Food Webs Ectoparasite – external parasites – do not enter hosts body Ticks, fleas, lice, leeches, mosquitoes Endoparasite – internal parasite – live inside host Disease causing bacteria, protists, tapeworm Affect the health and reproduction of the host Stimulates evolution of defenses in hosts Tough skin & chemically defended openings Eyes - tears Mouth - saliva Nose - mucus

13.4 Food Chains and Food Webs Natural selection favors adaptations that allow a parasite to efficiently attack host Specialized Anatomically - Mouth parts Physiologically - Body chemistry to survive different environments etc.

13.4 Food Chains and Food Webs Competition The use of a limited resource by 2 or more species Types Intraspecific- competition between organisms of the same species Interspecific- competition between 2 or more different species of organisms

Competitive Exclusion 13.4 Food Chains and Food Webs 14.1 Habitat and Niche Competitive Exclusion One species is eliminated from a community Natural selection favors differences between potential competitors – character displacement

Resource Partitioning 13.4 Food Chains and Food Webs Resource Partitioning Organisms “divide” resources Adaptations allow for use of resources in different ways or at different times Examples Diurnal vs. Nocturnal Add notes about generalist vs. specialist

13.4 Food Chains and Food Webs Mutualism Cooperative relationship in which both species benefit Some relationships are so close that neither species can survive without the other Ex: pollination

13.4 Food Chains and Food Webs Commensalism Interaction in which one species benefits and the other is not affected

Niche -Role of a species in its environment (Job) 14.1 Habitat and Niche Niche -Role of a species in its environment (Job) Types: Fundamental- ideal; absence of competition Realized- natural; competition and other constraints

Generalist vs. Specialist 14.1 Habitat and Niche Generalist vs. Specialist Broad niche Tolerate variety of resources and conditions Example raccoons Narrow niche Very specific adaptations Example Koalas

A habitat is all aspects of the area in which an organism lives. 14.1 Habitat and Niche A habitat is all aspects of the area in which an organism lives. biotic factors abiotic factors