Chapter 1 - Ecology and how to do it (CHAPTER + SLIDES) Flashcards
slides notes are included!!
First definition of ecology
“the comprehensive science of the relationship of the organism to the enviornment”
- Ernst Haeckel
Modern definition of ecology
“The scientific study and distribution and abundance of organisms, the interactions that determine that distribution and abundance, and the relationships between organisms”
Applied ecology
The earliest form of ecology. Managing the resources we have. (crops, livestock etc.)
- ecology has since moved on to being a “pure science”
Focused questions
- Focused questions that have meaningful information to be taken from their answer.
- ecology is full of many unanswered focused questions
Science’s 2 main goals
Explain & Understand
Understanding ecology
- Describing things
- Predicting things
Explaining ecology
- Proximate understanding
- Ultimate understanding
Proximate explanation
What is going on “here and now”
Ultimate explanation
What is going on evolutionary wise
Ranges of ecological scales
1) Time scales
2) Spacial scales
3) Biological scales
Biological Scales
(smallest)
1) Individual = one species
2) Population => same species, one location
3) Community => all populations, one location
4) Ecosystem => community + physical enviornment
5) Landscape
6) Biosphere => all life, scale of the whole planet
Spacial scales
Anywhere from micrometers to global scales.
General rules that apply in ecology no matter what biological scale we are looking at
1) Properties at a particular level arise out of the functioning of parts at the level below
2) to understand mechanistic reasons that a particular property is observed, one must look at the next lowest level of organization
3) properties observed at a given level of organization may be predicted without fully understanding the functioning at lower levels.
3 Time scales
1) Ecological Succession
2) Generation time
3) Lifespan of organism
…. 3.5??) Biological Immortality
Ecological Succession
The successive and continuous colonization of a site by certain species accompanied by the extinction or migration of others.
can be 1-2 days or 10K+ years
Generation time
The time from birth to fertility
Lifespan of organism
The time from birth to death
Biological Immortality
A stable or decreasing rate of mortality from cellular senescence as a function of chronological age.
3 types of ecological evidence
Observations & Monitoring
- example: watching the abundance of a species change over time
Experiments
Mathematical models
Manipulative field experiment
- change the surroundings around the area
Comparative field observations
- comparing data from dfiferent sites
Laboratory experiments
- controlled enviotnment
Ecological (mathematical) models
“an artificial enviornment to test ecological hypothesis”
- cannot expect real data
- summerize current knowledge
- doesn’t have to be full and perfect
- needs caution when applying it
- there is more confidence in answer when data is present
Statistics in ecology
Ecologists ‘seek simplicity but distrust it’
- statistics are regularly misused & you can never “prove” anything with statistics
- you can at most attach a level of confidence to your conclusions
- this level of confidence is usally achieved if P < 0.05 then your results are statistically significant
Natural experiment
An experiment that was not planned beforehand
- such as a glacier slide or a volcano rupture
Annual species
Those that complete a whole generation from seed to adult to seed again within a year.
- good at increasing abundance of a species rapidly
Perennial species
Those that live for several or many years and do not reproducein early stages
- increase abundance much slower than annual.
Hubbard brook: Manipulative field experiment EXAMPLE
- measurements were made of the quantity and chemical composition of water entering and leaving six water sheds
- in one of the watersheds all the trees were felled
- the overall export of dissolved organic matter rose 13x the normal rate
