Ecology Notes 2.1.3

Objectivs Identify and describe symbiotic relationships such as mutualism and parasitism. (middle school review) Exemplify various forms of communication and territorial defense including communication within social structure using pheromones(Examples: bees, ants, termites), courtship dances, territorial defense (Example: fighting fish). Explain patterns in predator /prey and competition relationships and how these patterns help maintain stability within an ecosystem with a focus on population dynamics.

Levels of Organization Species/organism- lowest level or organization Group of similar animals that can breed together and make a viable offspring

Levels of Organization Population – group of individuals that belong to the same species and live in the same area Example: the alligator population of Greenfield Lake

Levels of Organization Communities – groups of populations that live together in a defined area Example: the Cape Fear River community

Levels of Organization Ecosystem Organisms and nonliving environment they inhabit

Levels of Organization Biome – group of ecosystems with the same climate and similar communities.

The Biosphere (largest) The portion of the planet in which all life exists Land Water Air 8 km above Earth’s surface 11 km below the surface of the ocean

Carrying Capacity The largest number of organisms an environment can support Constantly changes as conditions and organisms change. What could cause the carrying capacity to increase?

3 Ecological Methods Observing- using your senses to gather data Experimenting- Changing variable to measure results Modeling- using observation and experimenting to make predictions

Which method? Experiment Observation Modeling Burning a pine forest to see which plants regrow first. Taking pictures of elephants from a distance. Using data, making a graph showing possible bacterial growth in salt water. Experiment Observation Modeling

What shapes an Ecosystem? Biotic Factors: living influences on organisms (ex. Trees, insects….) Abiotic Factors: physical, or nonliving factors Ex: weather

Ecosystem Niche: Organisms “occupation” (where it lives, its place in the food web etc.)

Community Interrelationships Competition: compete over resources, both suffer predation: one organism feeds on another, one benefits, other dies Symbiosis: any relationship where 2 animals live closely together

Types of Symbiosis Mutualism: both species benefit Ex. Flowers & insects Commensalism: one member benefits and the other is neither helped nor harmed ex. Barnacles 3. Parasitism: one organism lives on or in another and harms it. ex. tapeworms

Crash course Ecology https://www.youtube.com/watch?v=izRvPaAWgyw&list=PLQ5YDZyb2iavTT2f6nYMBBVFF-SLWHCz1&index=2

Ecosystem Stability Ecosystems are made of many living and nonliving factors. Because of all these influences ecosystems are both stable and fragile to change

Importance of Predation/competition Predator/prey relationships helps control both populations If one population grows too fast, the other slows it down Competition also keeps all populations stable and keeps one population from controlling a resource.

How ecosystems are stable… Predator/prey relationship keeps most populations in balance Symbiosis allows organisms to rely on each other to exist Biodiversity Many different types of organisms balance each other out

How ecosystems are fragile… Bioaccumulation/biomagnification When a toxin builds up in a ecosystem Ex; Mercury in fish Invasive/non-native species Have no predator and reproduce without limit Ex: Kudzu in NC Humans affects biodiversity Deforestation Habitat loss Non-sustainable use / over harvest

Social Behavior Communication within a population Common with insects such as bees, ants, and termites. Used to define social standing (queen vs worker bees) Pheromones- chemicals secreted by an organism that triggers a response in organism of same species Food trail pheromones Alarm pheromones Sex pheromones

Communication Animals may use visual, sound, touch or chemical signals to communicate Ex. Dolphins Cuttlefish- change colors

Courtship Occurs when an individual send out stimuli (sounds, visual displays, chemicals) in order to attract a mate

Courtship Dances Animals use a sequence of “Dance” moves to attract or signal a mate that its time to reproduce Common in birds, insects, and some fish Dance normally performed by male Sometimes accompanied by “song” sounds and the release of pheromones Courtship video and quiz http://www.planet-science.com/categories/under-11s/our-world/2011/02/love-in-the-animal-kingdom.aspx

Competition and Aggression Some animals are territorial Use aggression to defend territory and family Ex. Fighting Fish

Territorial defense Territorial- animals that actively defend their territory Few species are territorial, common in birds and large mammals Used to protect food, water, or reproductive purposes How? Mark their boundary using scent, sounds, or visual marks Deer scrape bark off trees, grunt, and urinate on the ground.

Predator Prey Patterns Predator eats prey Predator populations follow the change in prey populations. This keeps any one population from growing or shrinking too rapidly Competition also limits population sizes

Ocean Symbiosis https://www.youtube.com/watch?v=gFkdiCQxbyg&list=PLQ5YDZyb2iavTT2f6nYMBBVFF-SLWHCz1&index=1