Ecology +Biology

Baker-2015

• Ecology is the scientific study of interactions among organisms and between organisms and their physical environment. “Eco” meaning “home”, and “ology” meaning “the study of”. Thus ecology is the study of our home, Earth.

• There are Levels of Organization- from the smallest unit an “individual” all the way up to the whole globe our “biosphere”. Ecology can be studied at each of these levels and these levels tell us different information depending on the sample size.

• Levels of study increase from: – Individual – Population- is a group of individuals that belong to the same

species and live in the same area. – Community- a grouping of populations that live in a defined area – Ecosystem- all of the living and nonliving things in an area. – Biome- a group of ecosystems that share similar climates and

typical organisms – Biosphere-entire globe including both living and non-living things

Scope of Ecological Research

Organismal ecology

Population ecology

Community ecology

Ecosystem ecology

Landscape ecology

Global / Biosphere ecology

Biome ecology

Individual

• Rachel Carson is credited with starting the modern environmental movement with the publication of her book Silent Spring in 1962 on problems with the pesticide DDT.

• The environment we study in Ecology includes both the Biotic (living) and the Abiotic (non-living) features of the environment.

• All the biotic and abiotic factors that affect where an organism lives are the habitat of the animal.

• All living organisms have a range of environmental conditions that they can survive within and this is called the organisms tolerance. We can represent this with a tolerance curve. When an environmental condition (abiotic) extends in either direction beyond a organisms optimum range, the organisms experiences stress.

Biotic Abiotic

The Wolves

• https://www.youtube.com/watch?v=ysa5OBhXz-Q

• Wolves in Yellowstone N.P.

Take five minutes:

Please discuss an example situation where both an abiotic and biotic factor can affect an organisms success in the environment.

Different Methods for Coping with the Environment

• There are different methods for coping to the abiotic factors that are present in our environment. Animals can either try and regulate their internal environment or allow the environment to regulate their body.

• Regulators- an organism that expends energy to keep a stable internal environment to maintain homeostasis.

• Conformers- an organism whose internal environment is determined by that of their surroundings.

– We can think of these two generally as warm blooded and cold blooded.

• Acclimation- the ability of an organism to gradually (days to weeks) adjust to an environmental condition.

• Migration- method of avoiding unfavorable conditions by moving to a new geographical area that has more favorable conditions

• Hibernation- a period of time for an organism that is characterized by low body temperature, slow breathing, slow heart rate, and low metabolic rate.

Some of us get along with others while some of us do not...

• There are many types of interactions among organisms and they can affect the survival and reproduction of the species. These effects can be: positive (+), negative (–), or no effect (0) for either of the organisms.

• Competition is a (–/–) interaction between species when two species compete for a resource in short supply.

– Competitive Exclusion- when one species uses a resource so much more efficiently than another species that one is eliminated from an area.

– Character Displacement- Anatomical or habitual differences that arise in a species to avoid relying on a resource under competitive pressure

– Resource Partitioning- When two or more species that are competing for the same resource only utilize separate parts of that resource and prevent competition.

• Predation (+/–) refers to interaction where one species, the predator, kills and eats the other, the prey. (can include Herbivore = eating of plants)

• Symbiosis is a relationship where two or more species live in direct and intimate contact with one another including:

– Parasitism (+/– interaction)

– Mutualism (+/+ interaction)

– Commensalism (+/0 interaction)

EOC Review:

Please Review for Quiz 1

• Niche-is the range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce. (Location & Job)

• Competitive Exclusion Principle- no two species can occupy exactly the same niche in exactly the same habitat at exactly the same time.

• Fundamental Niche-The full range of environmental conditions and resources an organism can possibly occupy and use, especially when limiting factors are absent in its habitat.

• Realized Niche- The part of fundamental niche that an organism occupies as a result of limiting factors present in its habitat. (Fundamental-Limiting Factors = Realized)

Paramecium caudatum

Paramecium aurelia

Bozeman- Niche

• Niche-

• https://www.youtube.com/watch?v=z31y-ZtegZ8

• Generalist Species- able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources (for example, a heterotroph with a varied diet).

• Specialist species – can only thrive in a narrow range of environmental conditions or has a limited diet.

Ted Talk on Crows

• https://www.youtube.com/watch?v=bXQAgzfwuNQ

• What is the difference between a generalist and a specialist species? Give an example of each…

• Species Richness- How many different species there are in a community. (How many have we documented there)

• • Biodiversity- (or species diversity) How many different species there are in an area and how populous those species are in a community. (Numbers has to be at the population level)

• “In complexity comes stability” The more diversity in number of species a community is, the more that community can withstand disturbances. Communities that have low biodiversity are unstable and can collapse if a disturbance occurs.

• Ecological Succession-a series of more or less predictable changes that occur in a community over time. (especially after a disturbance ex. Fire or volcano)

• Primary Succession- succession that begins in an area with no remnants of an older community. (ex. Volcano)

• Pioneer Species-the first species to re-colonize a barren area after some catastrophic event. These organisms are often generalists, who reproduce and grow fast

• Secondary Succession- occurs when a disturbance affects the community without completely destroying it. (Ex. Fire)

• Climax Community- the final community in secondary succession, this community will not be replaced short of an environmental change or community destruction.

Primary Succession

Secondary Succession

http://epod.usra.edu/archive/images/img_8575.jpg

http://www.blm.gov/ca/surprise/fire_program/San Diego on fire.jpg

Autotrophs Heterotrophs

• Primary Producers- (Autotrophs) Organisms that can capture energy and convert it into forms that are usable for life. They use solar or chemical energy to create food. They are the basis of all life on earth because they produce more food than is required to survive and thus other life eats them.

– There are two methods for changing energy into useable forms for life:

1) Photosynthesis (Sun to sugars)

2) Chemosynthesis (Sulfur sugars) -This would occur deep in the ocean near volcanic vents

Autotrophs Heterotrophs

• Photosynthesis- the process of absorbing light, Carbon dioxide (CO2), and Water (H2O) to produce a sugar (Glucose, C6H12O6).

– The chemical reaction for photosynthesis is:

Sunlight + CO2 + H2O C6H12O6 + O2

• Cell Respiration is the process of breaking down glucose to make ATP and some electron carriers called FADH2 and NADH. These molecules pass their electrons onto the Electron Transport Chain (ETC) which acts like a water mill to pass H+ ions across the membrane. The H + ions are then used with ATP Synthase to produce ATP by slamming together ADP and P.

– The Chemical Formula for Cell respiration is:

C6H12O6 + O2 CO2 + H2O + ATP (Energy)

• Consumers (Heterotrophs)- organisms that cannot harness energy from the sun as producers must get energy from elsewhere. These organisms rely on other organisms for energy and nutrients.

• Types of consumers: 1°, 2°, and 3°

– Primary Consumers (1°) – organisms that eat producers and are also called herbivores.

– Secondary Consumers (2°)- organisms that eat primary consumers.

– Tertiary Consumers (3°)- organism that eat secondary consumers.

• These are relative terms, as an organism can occupy many of these categories because they eat many different types of organisms.

• Carnivores- kill and eat other animals.

• Herbivores- eat plants leaves, roots, seeds, or fruits.

• Omnivores- includes both plants and animals.

• Scavengers- eat carcasses of other animals after its been killed by a predator or disease.

• Decomposers- break down organic matter for energy. The left over stuff is called detritus.

• Detritivores- feed on detritus left over from decomposers.

• Food Chains: These are an energy transfer diagram that shows the energy flow from primary producers to primary consumers to secondary consumers and possibly to tertiary consumers.

• Food Web: This is a more complex and realistic representation of the energy transfer interactions that occur in nature. This may include multiple primary producers, primary consumers, secondary consumers or tertiary consumers.

• Ecological Pyramids have the producers on the base with the 1° and 2° and 3° ascending up the pyramid. The 10 % Rule states that only 10% of the energy is available to the next trophic level above. I.e. 100%10%1%0.1% of the total energy.

•

Response to competition –Competitive Exclusion- when one species uses a

resource so much more efficiently than another species that one is eliminated from an area.

–Character Displacement- Anatomical or habitual differences that arise in a species to avoid relying on a resource under competitive pressure

–Resource Partitioning- When two or more species that are competing for the same resource only utilize separate parts of that resource and prevent competition.

Resource Partitioning

• http://www.census.gov/popclock/

• Carrying Capacity (K)-is the maximum number of individuals of a particular species that a particular environment can support. Once a population reaches the carrying capacity of its environment, a variety of factors act to stabilize it at that size.

• What is the human population’s carrying capacity?

• At each new technological advance (i.e. Farming, Industrial Revolution, Advances in Medicine) creates a new “artificial carrying capacity”.

R or K Selected Species

R Selection- • Favors unstable

environment

• Small body size

• Early Maturation

• Short Gestation Period

• Lots of Offspring

• Ex. Dandelions, Bacteria

• Named r for reproduction

K Selection-

• Favors stable environment

• Large body size

• Long life expectancy

• High Parental Care

• Few offspring

• Ex. Elephants, Primates

• Named K for carry capacity