Ecology

Ecology: AbioticBiotic: Levels of Organization Habitat Niche Capacity Competition Feeding Relationships Symbiotic Relationships Trophic Levels Carrying

WHAT IS ECOLOGY? Ecology- the scientific study of interactions between organisms and their environments, focusing on energy transfer Ecology is a science of relationships

WHAT DO YOU MEAN BY ENVIRONMENT? The environment is made up of two factors: Biotic factors- all living organisms inhabiting the Earth Abiotic factors- nonliving parts of the environment (i.e. temperature, soil, light, moisture, air currents)

Organism Population Community Biosphere Ecosystem

Organism – a single individual representing a species The lowest level of organization

POPULATION a group of organisms of one species living in the same place at the same time that interbreed Produce fertile offspring Compete with each other for resources (food, mates, shelter, etc.)

Community - Populations of different species interacting within an ecosystem.

Ecosystem - populations in a community and the abiotic factors with which they interact (ex. marine, terrestrial)

Biome- regional or global community of organisms characterized by the climate conditions and plant communities that thrive there

Biosphere – where all life exists on Earth. The highest level of organization

Habitat Niche Carrying Cap. Competition Fundamental Niche- Realized Niche- Limiting factor- Carrying Capacity - Interspecific competition- Intraspecific competition-

Habitat vs. Niche Niche - the role a species plays in a community; its total way of life Habitat- the place in which an organism lives out its life

Niche: 2 Types Fundamental niche- – includes the total range of environmental conditions and roles that a species could theoretically fulfill Ex- You COULD theoretically clean the dishes, dust, vacuum, wash clothes, iron, fold towels, sweep & mop EVERY DAY.

Niche: 2 Types Realized niche- –The roles that the species actually fulfills These are the chores you actually do. You might have really washed the dishes and that was it.

Habitat vs. Niche A niche is determined by the tolerance limitations of an organism, or a limiting factor. Limiting factor- any biotic or abiotic factor that restricts the existence of organisms in a specific environment.

Examples of limiting factors - Amount of water Amount of food Temperature Amount of space Availability of mates Habitat vs. Niche

Carrying Capacity the maximum population size that can be supported by the available resources There can only be as many organisms as the environmental resources can support

Survivorship curves Type 1 TYPE I –Most individuals survive childhood and middle age –rapidly decline in old age –Example: humans 02 June 2010Populations.ppt19

Survivorship curves TYPE II –Roughly a constant mortality rate throughout individual’s life span Example: birds 02 June 2010Populations.ppt20

Survivorship curves TYPE III –Most individuals will die early in life and not make it to adulthood –Example: frogs, plants 02 June 2010Populations.ppt21

Competition Interspecific competition  individuals of different species compete for the same resource in an ecosystem Intraspecific competition  members of the same species compete for limited resources

Feeding Relationships There are 3 main types of feeding relationships 1. Producer - Consumer 2. Predator - Prey 3. Parasite - Host

Producers: Consumers: 1.Herbivores 2. Carnivores 3. Scavengers 4. Decomposer Omnivores: Feeding Relationships

Producer- all autotrophs (plants), they trap energy from the sun Bottom of the food chain They do photosynthesis 6CO 2 +6H 2 O +sunlight  6O 2 + C 6 H 12 O 6

Feeding Relationships Consumer - all heterotrophs: they ingest food containing the sun’s energy Do cellular respiration C 6 H 12 O 6 + O 2  CO 2 + ATP + H 2 O  Herbivores  Carnivores  Omnivores  Decomposers

Feeding Relationships CONSUMERS 1.Primary consumers Eat plants Herbivores Secondary, tertiary … consumers Prey on animals Predators Carnivores

Feeding Relationships Consumer-Carnivores-eat meat Predators –Hunt prey animals for food.

Feeding Relationships Consumer- Carnivores- eat meat Scavengers –Feed on carrion, dead animals “Detritivores”

Feeding Relationships Consumer- Decomposers Breakdown the complex compounds of dead and decaying plants and animals into simpler molecules that can be absorbed

Feeding Relationships Consumer- Omnivores -eat both plants and animals

MutualismCommensalismParasitism Ex- Ex- Ex Symbiotic Relationships

Symbiosis- two species living together 3 Types of symbiosis: 1. Commensalism 2. Parasitism 3. Mutualism

Both organisms benefit from the relationship Organism One Organism Two Mutualism

Both organisms benefit from the relationship The otters help the kelp by eating the sea urchins which endanger it. The kelp provides and anchor for the otters while they sleep. Otters and Kelp

The Chital and the Tree-pie The tree-pies help the chital by stripping the dead velvet from the antlers. This provides them with nourishment Therefore both species are benefiting from this symbiotic behavior.

Cleaner Fish and the Moray Eel The cleaner fish eats parasites and food bits out of the inside of this moray eel. It gets a meal and is protected from predators by the fierce eel.

Lichen Lichen is really two organisms: algae and fungus. The fungus needs food but cannot make it. The algae makes food but needs some way to keep moist. The fungus forms a crust around the algae which holds in moisture. Both organisms benefit.

Swollen Thorn Acacia Tree and Ants The tree provides a nursery for the ants in the thorns and makes special food for the ant babies. In return the ants sting and attack any other plants or insects that try to invade the tree.

Commensalism One species benefits while the other is unaffected Organism One Organism Two

Commensalism One species benefits while the other is unaffected The cattle help the egret who look for grasshoppers and beetles that are raised by the cows. Now and then they sit on the back of a cow, looking for ticks and flies. This does not effect the cattle in any way. The cattle egret and cows

Barnacles and Whales Barnacles need a place to anchor. They must wait for food to come their way. Some barnacles hitch a ride on unsuspecting whales who deliver them to a food source. This does not effect the whale in any way.

Oak Gall Wasps and Oak Trees The oak gall wasp stings the oak tree. the tree then grows a GALL which is a nest for the wasp’s babies. When the larva hatch, they eat their way out of the gall. Does not help or hurt the oak tree

Parasitism One species benefits while the other is harmed Organism One Organism Two

Parasitism One species benefits while the other is harmed Mistletoe is an aerial parasite that has no roots of its own and lives off the tree that it attaches itself to. Without that tree it would die. It slowly chokes out the life of the host tree.

Bedbugs Bedbugs are small, nocturnal parasites that come out of hiding at night to feed on unsuspecting humans. They feed exclusively on blood! Their bites often result in an allergic reaction.

Tapeworms The definitive host of the cucumber tapeworm is a dog or a cat (occasionally a human). Fleas and lice are the intermediate host. the dog or cat becomes contaminated when the eggs are passed in the feces, and the flea or louse ingests the eggs. The dog or cat (or human) is infected when they ingest a flea or louse. Hence the importance of controlling fleas on your pet!

Type of relationship Species harmed Species benefits Species neutral Commensalism Parasitism Mutualism = 1 species

Trophic Levels Each link in a food chain is known as a trophic level. Trophic levels represent a feeding step in the transfer of energy and matter in an ecosystem.

Trophic Levels Biomass- the amount of organic matter comprising a group of organisms in a habitat. As you move up a food chain, both available energy and biomass decrease. Energy is transferred upwards but is diminished with each transfer. Only 10% of energy is moved from one level to the next

Trophic Levels Producers- Autotrophs Primary consumers- Herbivores Secondary consumers- small carnivores Tertiary consumers- top carnivores ENERGYENERGY

Trophic Levels Food chain- simple model that shows how matter and energy move through an ecosystem

Trophic Levels Food web- shows all possible feeding relationships in a community at each trophic level Represents a network of interconnected food chains

Food chainFood web (just 1 path of energy) (all possible energy paths)

Toxins in food chains- While energy decreases as it moves up the food chain, toxins increase in potency. This is called biological magnification Ex: DDT & Bald Eagles

Nutrient Cycles Cycling maintains homeostasis (balance) in the environment. 3 cycles to investigate: 1. Water cycle 2. Carbon cycle 3. Nitrogen cycle

Water cycle- Evaporation, transpiration, condensation, precipitation

Water cycle-

Carbon cycle- Photosynthesis and respiration cycle carbon and oxygen through the environment.

Carbon cycle-

Nitrogen cycle- Atmospheric nitrogen (N 2 ) makes up nearly 78%-80% of air. Organisms can not use it in that form. Lightning and bacteria convert nitrogen into usable forms.

Nitrogen cycle- Only in certain bacteria and industrial technologies can fix nitrogen. Nitrogen fixation-convert atmospheric nitrogen (N 2 ) into ammonium (NH 4 + ) which can be used to make organic compounds like amino acids. N 2 NH 4 +

Nitrogen cycle- Nitrogen-fixing bacteria: Some live in a symbiotic relationship with plants of the legume family (e.g., soybeans, clover, peanuts).

Nitrogen cycle- Some nitrogen-fixing bacteria live free in the soil. Nitrogen-fixing cyanobacteria are essential to maintaining the fertility of semi-aquatic environments like rice paddies.

Atmospheric nitrogen Lightning Nitrogen fixing bacteria Ammonium Nitrification by bacteria NitritesNitrates Denitrification by bacteria Plants Animals Decomposers Nitrogen Cycle