What is Ecology?What is Ecology?

Interactions between Interactions between organisms & organisms & environment environment

Interdisciplinary: Interdisciplinary: chemistry, physics, chemistry, physics, geology, mathgeology, math

Statistical model of roads built in tropical rainforest by the year

2060

Where does life Where does life exist?exist? Geologic regionsGeologic regions

AtmosphereAtmosphere – layer of – layer of gasesgases

LithosphereLithosphere – land part – land partof Earth (rock, soil, sand)of Earth (rock, soil, sand)

HydrosphereHydrosphere – all – all Earth’s waterEarth’s water

BiosphereBiosphere All the spheresAll the spheres

Portion of Earth that supports lifePortion of Earth that supports life

How much of the Earth How much of the Earth do you think this region do you think this region

takes up?takes up?

2 types of factors influence 2 types of factors influence organism’s environmentorganism’s environment

1.1. AbioticAbiotic – – nonliving nonliving elements (rain, elements (rain, wind, soil, wind, soil, temperature)temperature)

2.2. BioticBiotic – living – living factors factors

Ecological OrganizationEcological Organization

OrganismOrganism – has all – has all characteristics of lifecharacteristics of life

PopulationPopulation – group of – group of organisms living organisms living together at same time; together at same time; reproducereproduce

CommunityCommunity – several populations in – several populations in same area at same timesame area at same time

EcosystemEcosystem – interactions – interactions between populations in a between populations in a community & abiotic community & abiotic elements in their elements in their surroundingssurroundings HabitatsHabitats NichesNiches Species interactionsSpecies interactions

Niche & HabitatNiche & HabitatHabitat –where organism lives out its life

Includes abiotic & biotic factors

Not static

Niche – organism’s role & location in its environment to meet unique needs

How organism:

Obtains food

Finds shelter

Reproduces

Reduces competition

Influences on Ecosystems

Natural & human causes

Can you think of any examples of things that might

influence a habitat?

Examples

Natural Disasters: a) Hurricane Katrina, 2005

Before

After

b) Volcanic Eruptions: Mount St. Helens, Washington State

May, 1980

Before

After

c) Weather patterns: Regular & extreme weather

conditions

Predator-prey Relationships

• One organism seeksanother for food

• Maintains balance• Prey species may benefit

(↓ competition, ↑ food)

Predator Strategies• Ambush• Camouflage

Prey Strategies1. Defensea) Quick escape

b) Predator detection

Nebraskan cockroach

Meerkat keeping watch

c) Protective shells, bark, spines

d) Camouflage

Red-eared slider

Porcupine

Stick bug

2. Chemical warfare – poisons, odors, irritants, unpleasant taste

**Organisms using this strategy often have bright, warning colors

3. Behavior – mimicry, group size

Viceroy

Monarch

Skunk

Symbiotic Relationships(close association)

3 types:1. Parasitism – feeds on and lives on/in host; ( +, - )

Deer tick - parasite

White-tailed deer - host

2. Mutualism – ( +, + )– Pollination– Food supply

– Protection

Rhinoceros and Horn-billed Puffin/

Rhinoceros Auklet

Clownfish and Sea Anemone

3. Commensalism – ( +, o )

Grey whale and Barnacles

Competition

• Intraspecific – between members of same species– Fight for same resources

• Habitat• Nutrients • Water• Soil

– Abundant resources = sharing

Example: Blue satin bower bird

• Interspecific –between members of different species

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Resource use

Resource use

Species 1Species 1Species 2Species 2

RegionRegionofof

niche niche overlapoverlap

Species 1Species 1 Species 2Species 2