Chapter 2 Principles of Science and Systems revision Flashcards
What are the Basic Principles of Science?
- Empiricism
- Uniformitarianism
- Parsimony
- Uncertainty
- Repeatability
- Proof is elusive
- Testable questions
Empiricism in science is …
we can learn about the world by careful observation of empirical phenomena; we can expect to understand laws and processes.
Uniformitarianism in science is …
basic patterns and processes are uniform across time and space.
Parsimony in science is …
when two plausible explanations are equally reasonable, the simpler one is preferable. Also called Ockham’s Razor.
Uncertainty in science is …
knowledge changes as new evidence appears, and explanations (theories) change with new evidence.
Repeatability in science …
there is an expectation that tests and experiments can be repeated.
Proof is elusive in science …
we rarely expect science to provide absolute proof, since new evidence can undermine our current standing.
Testable questions in science …
to find out whether a theory is correct, it must we tested.
Logical ordering of steps:
- Identify question
- Form a testable hypothesis
- Collect data to test the hypothesis
- Interpret results (if hyp. is rejected, step 2)
- Report for peer review
- Publish findings.
Inductive reasoning …
deriving a general rule from observations.
Deductive reasoning …
deducing an explanation from general principles.
Scientific theory refers to …
an idea that is overwhelming back up with evidence.
Experimental design: Natural Experiments are …
observed natural events and interpreting a casual relationship (e.g. a link between colds and sleep deprivation).
Experimental design: Manipulative Experiments are …
where conditions are modified deliberately, and all other variables are held constant (can be referred to as a controlled study).
A controlled study:
by comparing a treatment (exposed) group and a control (unexposed) group. Blind experiments are important here.
Blind and double-blind experiments are …
blind experiments: researcher doesn’t know which group is treated until after the analysis of the results.
double-blind experiments: neither the subject nor the researcher knows who is in the treatment group and who is in the control group.
Independent variable (IV):
the stable and unchanged variable.
Dependent variable (DV):
the affected and changed variable.
Define ‘ecosystem’
a complex assemblage of animals, plants and their environment, through which materials and energy move.
Define ‘systems’
networks of interdependent components and process, with materials and energy flowing from one component to another, that together have properties beyond those of individual parts.
Homeostasis is …
the ability to maintain stability.
State variables (or compartments) …
store energy, water and matter; e.g. animals and plants.
Open systems are …
those that receive inputs from their surroundings and produce outputs.
Closed systems …
exchanges no matter or energy with its surroundings; like a fishbowl (although it receives energy from the sun) it doesn’t have much, or any, interactions.
Positive vs. Negative feedback:
Positive feedback is a self-perpetuating process; whereas Negative feedback, is a process that suppresses change.
What are ‘disturbances’?
What are ‘positive disturbances’?
What are ‘negative disturbances’?
Disturbances are events that can destabilize systems.
A positive disturbance means that the ecosystem can recover from the disaster, or need the disturbance to regenerate (resilience).
A negative disturbance means that the ecosystem struggles to, or cannot, recover from the disaster.
What is ‘resilience’ (in regards to positive disturbances)?
an ecosystem’s ability to recover from a disaster.
What is ‘state shift’ (in regards to negative disturbances)?
state shift means that conditions do not return to normal after a disaster.
What are ‘emergent properties’?
multiple uses; for example, a tree provides shade, habitat and food, stores carbon, and cools the ground.
Scientific consensus …
ideas and information are exchanged, debated, tested and retested to arrive at a scientific consensus. It is a general agreement among informed scholars.
Paradigm shifts …
occur when a majority of scientists accept that the old explanation no longer explains new observations.
Environmental attitude 1. any person who believes that the condition & nature of the environment are always important factors in any decision made relating to the use or management of land, water and resources.
Environmentalist
Environmental attitude 2. the environment, nature, deserves to exist for its own sake, regardless of its usefulness to us.
Biocentric preservation
Environmental attitude 3. social move towards environmental protection & conservation through increasing awareness of environmental issues.
Environmentalism
Environmental attitude 4. the basis that the environment should be saved not because it is beautiful or because it shelters wild life, but only to provide homes and jobs for people.
Utilitarianism conservation
