Ecology > Text reference: Chapter 2 The study of how organisms interact with each other and with their environment.
ABIOTIC FACTORS : non-living parts of the environment Examples: temperature, precipitation, wind, soil, sunlight, etc.
BIOTIC FACTORS: living components
Abiotic and Biotic factors affect each other! Example: Strip mining affects...
Levels of Organization
1. Organism: a single living thing
2. Population: a group of organisms of the same species living in the same area.
Species: Organisms that look alike, can mate and produce fertile offspring Organisms that look alike, can mate and produce fertile offspring (a horse and a donkey look alike and can mate, but are separate species since they cannot produce fertile offspring (mule)
3. Community: all of the populations in a particular area. Ex.: zebra, elephants, giraffes are part of this community
4. Ecosystem: a community interacting with the abiotic environment.
Ex. Ocean ecosystem
Ex. Desert ecosystem
Ex. Ocean vent ecosystem
Ex. Freshwater ecosystem
Biome: "the world's major communities” (classified by the predominant vegetation and characterized by adaptations of organisms to that particular environment) "the world's major communities” (classified by the predominant vegetation and characterized by adaptations of organisms to that particular environment)
5. Biosphere: The portion of the earth that supports life (high in atmosphere to bottoms of oceans!)
Habitat vs. Niche Habitat : where an organism lives. Ex. Sharks usually live in a marine habitat Niche : what an organism does Ex. Sharks are carnivores, they swim quickly and have sharp teeth.
Habitat: ocean Part of its niche: eats seals Example:
What happens when 2 species share the same niche?
Competition!!!!
How Do Organisms Obtain Energy?
1. Producers = Autotrophs Most do Photosynthesis (use light energy to make food)* (a few do Chemosynthesis– remember ocean vents) All other organisms in the biosphere are dependent on them they are at the bottom of every food chain!
cannot make their own food. feed on autotrophs or other heterotroph; 2. Consumers = Heterotrophs
What kind of heterotrophs are there? 1.Herbivore 2.Carnivore 3.Omnivore 4.Scavenger (feed on dead organisms) 5.Decomposer (take over where scavengers leave off)
Symbiosis: A close relationship between 2 species for a prolonged period of time.
3 kinds of symbiosis:
Ex: The stinging anemone protects the clownfish from predators; the clownfish protects the anemone from angelfish that would eat it and also keeps the anemone free of dirt and debris. 1. Mutualism: (+,+) both species benefit.
Ex: The barnacle larvae swim around, attach to the whale, and form the adult. As whale swims, barnacles get new food from water. The whale does not appear to be harmed. 2. Commensalism (+, 0): one species benefits and the other is not affected.
3. Parasitism (+, -): one species benefits and the other species is harmed. Example #1. Tomato horn worm and wasp
Example #2. Cowbirds are “brood parasites”
What kind of relationship are each of the following?
#1: Bacteria/Plant root Bacteria in the nodules of many plants can take nitrogen gas from the atmosphere and turn it into a form that can be used by the plant; the plant protects the bacteria from harmful oxygen and the bacteria get food from the plant.
#2: Heartworm/Dog The worm larvae are transferred from dog to dog through the bite of an infected mosquito. The mosquito sucks larval heartworms with blood from an infected dog. The mosquito then bites another dog and transfers these microscopic larva as it bites. During the next few months, these larva migrate through the dogs body arriving at the heart several months later where they become adults.
#3: Oxpecker/Mammal The oxpecker eats parasites on the mammal.
#4: Cattle/Egret The cattle stir up grasshoppers and other insects that the egret likes to eat.
#5: Misletoe/Tree Mistletoe lives off the branches and stems of other trees. It can photosynthesize a little but not enough to meet its needs. The tree can be harmed.