Chapter 2 - Principles of Ecology

2.1 Organisms & Their Relationships

What is Ecology?

Scientific study of interactions between organisms and their environments

Reveals interrelationships between living (biotic) and nonliving (abiotic) parts of the world

Combines information from math, chemistry, physics, geology, other branches of biology

Ecology Video

Biosphere

bio = life, sphere = areathe portion of Earth that supports

lifeextends from high in the

atmosphere to the bottom of the ocean

Biotic factors

bio = life, tic = relating toall living organisms that inhabit an

environmentexamples: animals (humans),

Plants, Protists, Bacteria, fungi

Abiotic factorsa = notnonliving parts of the environment

that effect living thingsexamples: air currents, water

currents, temperature, water pressure, rocks, sand, soil, moisture, light

Abiotic Factors Video

Levels of Organization (p. 36)OrganismPopulationCommunityEcosystemBiomeBiosphere

Organisms

an individual living thing

Populations group of organisms of one species living in

the same place at the same time that interbreed, compete with one another for food, water, mates, and other resources; a change in one population will affect other populations

No population of organisms of one species lives independently of other species.

Communities

made up of several populations interacting with each other

Ecosystem

all the biotic and abiotic factors in an area

the interactions among the populations in a community and the community’s physical surroundings, or abiotic factors

Terrestrial Ecosystems

located on land examples:

ForestsMeadowsDesert

Aquatic Ecosystems

fresh water ecosystemsexamples: ponds, lakes, and streams

salt water (marine) ecosystemsexamples: oceans, seas, large lakes

“Great Salt Lake”

Biome

Ecosystems that share the same climate and have similar types of communities

Ex. Marine biome

Biosphere

the entire planet and all its living and nonliving parts and how everything interacts

Habitat

Place where an organism lives its life

Can change or even disappearOrganisms must adapt to the

changes or they will die.

Niche p. 38

the role a species plays in a community

although several species may share a habitat, the food, shelter, and other resources are divided into separate niches

Niche examples:

coyotes in a grassland community help keep down the rodent population

fungi in a forest helps breakdown of organic matter contained in the bodies of dead organisms to recycle nutrients

Symbiosis

“living together”the relationship in which there is a

close and permanent association between organisms of different species

different kinds of symbiosis:

Commensalism

one species benefits and the other species is neither harmed nor benefited

Commensalism

example: large trees such as oaks provide a habitat for Spanish moss

Remoras live very close to sharks. The shark does not bother the remora, but the remora eats the leftover food the shark drops or does not eat.

Mutualism

both species benefit

Ants and Acacia Tree

Mutualism

An unidentified crab that carries a venomous sea urchin for protection. The crab uses its rear legs to hold the urchin in place. The urchin receives transportation.

The Sponge Crab is wearing a "hat" that consists of a living sponge colony. The sponge gains transportation while the crab gains a disguise.

The Tomato Anemone Fish lives among the Sea Anemone. It gains protection from predators while the anemone gains dinner.

Parasitism

one species is harmed, but usually does not kill the host

examples: tapeworms, roundworms, ticks, fleas

Isopods are crustaceans, some of which are parasites. Isopods known as "fish lice" attach themselves to their host and feed on its body fluids.