Intro to Ecology
Structure of living things
Life is organized by levels
-Atom
-Molecule- Two or more atoms bonded together
-Cell- The smallest unit of life
-Tissue- A group of similar cells
-Organ- A group of similar cells working together
-Organ System- A group of organs working together
-Multicellular Organism- A complete living thing
-Species- Organisms that can reproduce and produce a fertile, viable, offspring
-Population- A group of the same species
-Community- All the species in an area
-Ecosystem- All the biotic (living) and abiotic (non-living) things in an area
-Biosphere- The earth
Ecology is the relationship of organisms to their environment and other organisms
Ecology can be broken down into many different levels
Global Ecology
Landscape Ecology
Ecosystem Ecology
Community Ecology
Population Ecology
Organismal Ecology
Before we get into organisms and their relationship with their ecosystem it is good to understand why we have different ecosystems
Get into groups of four. In your group you are going to have a discussions. With your partners you are going to answer these questions.
-How long does it take the earth to rotate on its axis once?
-How long does it take for the moon to orbit the earth once?
-How long does it take the earth to orbit the sun once?
-What are ocean tides?
-What causes ocean tides?
-What are seasons?
-What causes seasons?
-Are seasons the same in all parts of the earth?
It is okay if you do not know the answers to some of these questions. If you don't know then guess. You need to have an answer but it is okay to be wrong. We will discuss it together afterwards.
The Sun, Earth, and Moon Orbit Simulation
Google Moon We all know there is a google earth but did you know there is a google moon? We can explore the moon!
Ocean Tides the effect the moon and sun have on earth tides
Phases of the Moon
Seasons!
Why do we have seasons Part 1 Is it because of how close we are to the sun?
Why do we have seasons Part 2 is it because of the earth's tilt?
Wind, Clouds, and Current
Water pressure demonstration
When matter is removed from space it creates a vacuum that must be filled
Heat rises and as it does new matter must take its place. This new matter is usually cooler than the heated matter that rises
Demonstration on heat rising
-How does this compare to weather? To wind? To water currents?
-How does this affect Los Angeles and our smog?
Air Pressure
Surface Circulation
-The wind drives the strongest ocean currents which occurs on the surface layer
-Wind and surface currents are ultimately caused by heat from the sun
-Wind and currents are also influenced by the Coriolis Effect
The Coriolis Effect
-Because the earth is round, anything that moves across the earths surface tends to turn a little instead of moving in a straight line.
Wind Patterns and Weather
Rain Shadows
The water from the ocean evaporates and rises to form clouds. The clouds blow inland. Once they reach a mountain that is too tall to pass they rain. The water travels down the mountain and works its way back to the ocean. The wind continues past the mountains but since the clouds did not make it over it is a dry wind. On the other side of coastal mountains is usually a desert because the air at that point is dry. This is called a rain shadow.
The Sierra Nevada Mountains
Animals and their interactions with their environment
Habitat- A habitat is all the biotic and abiotic characteristics in an area where an animal lives
Each organism has its own Niche
-A niche is what you eat, the land you take up, and how you live
-If another organism has the same niche then they are competition for each other
-Most organisms in the same ecosystem develop a slightly different niche to avoid competition
-Interspecific competition- When different species compete
-Intraspecific competition- When members of the same species are competing
Growth Rate
Growth rate = Birth rate - Death rate
r = b - d
Things that affect biotic potential
-The age at which the organism first reproduces
-The frequency at which reproduction occurs
-The average number of offspring produced each time the organism reproduces
-The length of the organism's reproductive life span
-The death rate of the individuals under ideal conditions
Boom and bust populations - have as many offspring as possible and then die out every season
-Flies and most insects
Logistic growth - Grow to the maximum level the environment can handle and then stabilize
Carrying capacity
-Each ecosystem has a carrying capacity for each of its organisms
-The carrying capacity is how large of a population that ecosystem can support
-K stands for carrying capacity
-A J-Curve represents exponential growth
-An S-Curve is when exponential growth evens out with its carrying capacity
-An S-Curve represents logistic growth
Predators and Prey affect each others carrying capacity
Human Population Growth
Environmental Resistance
-Density-independent - factors that limit population size regardless of the population density
-Density-dependent - Population is controlled once it reaches its carrying capacity