Ecology

Ecology is the study of interactions among organisms and their environment.

Ecologists are scientists who study these relationships. Ecologists divide the environmental factors that influence organisms into two groups (abiotic and biotic factors).Many times, ecologists must travel to specific environments to examine the organisms that live there.

Biome - a large geographical area having the same climate and major life forms. A habitat is where an organism lives within an ecosystem.In an ecosystem you have three classes of consumers:Herbivore - eats plants onlyCarnivore - eats meatOmnivore - eats bothA ecosystem is a group of organisms & their physical environment.

An ecosystem is the biotic community and its abiotic factors. Examples of ecosystems include coral reefs, forests, and ponds.

The carrying capacity is the maximum population size that can live in an environment over time.

A limiting factor is a biotic or abiotic factor that restricts the size of a population.Food can be a limiting factor if the amount of food can only support a certain number of an animal in a population.

Biotic factors are the living or once-living parts of the environment (plants, animals-prey, etc)Abiotic factors are the nonliving parts of the environment (light, water, air, nutrients, soil, minerals, nesting sites)

What are the biotic and abiotic factors in this picture?http://www.thegardenhelper.com/102902.JPG

CowsGrassTreesShrubsOthers unseenAirWaterSoil, rocksLight Temperature

The total number of species and biological communities in a region and the amount of genetic variation in each speciesThe loss of biodiversity is a huge ecological problemGenetic diversity decreases as its populations decline- consequences in a population to adapt to changing environmentGenetic variability-measure of its potential to adapt; evolutionary insurance policy

Limit pollution (air, soil, water)Control transport of invasive speciesLimit the use of natural resources (clear cutting rainforests, interfering with river flow to wetlands, slow down oil and gas consumption)Conserve natural resourcesProtect endangered species (plants and animals)

The interaction between two or more organisms, or groups of organisms, that compete for the same resources (in short supply)Can be between members of the same species and/or members of the different speciesMost important aspects of natural selectionResults:reduction in the numbers of one or both competitors- Distribution of organisms in habitats

A living thing thatmakes food usingmaterials from the environment (nutrients)& the Sun. Primary - uses food producedby plants (eats plants)Secondary - obtains energy by eating primary consumer (eats meat)Living things that eatthe remains and waste of plants andanimals. Like bacteria, It breaks down organic material.

Producers are plants:GrassTreesFlowersWeedsThe produce energy through photosynthesisConsumers are animals (including humans):Bacteria (also decomposer)insectsrodentsdog/wolf/foxbears

INTERACTIONS AMONG ORGANISMS Predator-prey An animal that hunts or kills other animals for food is called a predator.An animal that is eaten by another is called prey.

Can you match some predator-prey relationships?

Predator Prey

SymbiosisSymbiosis is a long term relationship between 2 or more species - Mutualism both organisms benefitex. Coral (home) and algae (food)- Commensalism One organism is helped, while the other is neither helped or harmedex. Remoras ride on sharks and eat what they leave behind in food scraps- Parasitism one benefits (parasite) the other is harmed (host) and weakenedex. ticks

A living thingAll organisms of the same species that live in the same place.Population that shares an areaAll populations within acertain area.

Food Chain, Webs, and Pyramid

ENERGY FLOW AMONG ORGANISMSEverything you do requires energy. How do you get the energy that you need?

All living things get energy from their food to carry out life processes.

Plants make their food.Animals eat their food.

A food chain shows how each living thing gets its food. Plants make food using energy from the sun. Some animals eat plants and some animals eat other animals. Each link in a chain is food for the next link. Arrows indicate the direction of energy flow.

A food chain is the passing of food energy from one organism to another.

Plants are called producers because they are able to use the energy from the sun to produce the food they need using carbon dioxide and water.

Animals cannot make their own food so they must eat plants and/or other animals. They are called consumers. There are three groups of consumers.

HERBIVORESAnimals that eat ONLY PLANTS are called herbivores.http://www.gpnc.org/pronghor.htm

CARNIVORESAnimals that eat OTHER ANIMALS are called carnivores.www.desertusa.com/

www.desertusa.com/http://www.orcahome.de/orcafact.htm

OMNIVORESAnimals that eat BOTH animals and plants are called omnivores. http://www.loomcom.com/raccoons/gallery/jpegs/raccoon1.jpghttp://animaltrial.com/animals/bearpicturesfolder/blackbearpictures/blackbearwalking.htmlAmerican bearRaccoon

A herbivore is called a primary, or first order consumer because it eats the producers.A carnivore that eats herbivores is a secondary, or second order consumer.Some predators are called tertiary, or third order consumers. These animals usually have no predators.

Some animals eat dead animals or carrion. They are called scavengers. They help break down or reduce organic material into smaller pieces. http://www.factmonster.com/ipka/A0768543.htmlhttp://www.mbr-pwrc.usgs.govhttp://pested.unl.edu/amerroa.jpgroachhyeinavulture

DECOMPOSERSOrganisms (bacteria and fungi) which feed on decaying matter.

Decomposers and scavengers break down dead plants and animals. They also break down the waste (feces) of other organisms. Decomposers are very important for any ecosystem. If they weren't in the ecosystem, the plants would not get essential nutrients, and dead matter and waste would pile up.

Why are there more herbivores than carnivores? In a food chain, energy is passed from one link to the next. When a herbivore eats, only a fraction of the energy that it gets from the plant food becomes new body mass; the rest of the energy is lost as waste or converted to heat (by the herbivore).

Likewise, when a carnivore eats another animal, only a portion of the energy from the animal food is stored in its tissues. In other words, organisms along a food chain pass on much less energy (in the form of body mass) than they receive.

ENERGY PYRAMIDBecause a large amount of energy is lost at each link, the further along the food chain you go, the less energy is available.We use the energy pyramid as a model to show decreasing available energy at each level in the pyramid.

100% energy10% energy

1% energy0.1% energy

FOOD WEBS Most organisms are part of more than one food chain. Many animals eat more than one kind of food in order to meet their food and energy requirements. These interconnected food chains form a food web.

All energy comes from the sun - which makes it the top of the food chain.

MARINE FOOD WEBhttp://www.gould.edu.au/foodwebs/kids_web.htm

Photosynthesis

6CO2 + 6H20 + energy (sunlight) C6H12O6 (glucose)+ 6O2

Energy from Sun is used to fuel a chemical reaction between carbon dioxide and water producing glucoseProcess which plants use CO2 from air to make sugarsReproduces OxygenMakes food for energy

Ecological Succession- the orderly changes in a ecosystem as one type of community changes into anotherPioneer species lichens and mosses live in area and grow on rocks, releasing acids that break them down over time to form soil

Plants start to grow in soil

Small animals move into area

Large animals feed on smaller animals

Organisms die leaving richer soil supported larger plants shrubs

Soil becomes richer supporting trees

Reaches a stable point of established growth know as a climax community