eco final lab Flashcards
What is a Naturalist?
- an expert in or student of natural history
- Someone who studies flora and fauna,
fossils, geology
What is an Ecologist?
an environmental scientist who studies how organisms interact with their environment and how the environment functions.an expert in or student of ecology
Ricklefs’ definition of Ecology
The scientific study of the abundance and distribution of organisms in relation to other organisms and environmental conditions.
Geographical range
Where are organisms is present and where it is absent
Abundance
how many individuals of a particular organisms are in a certain area
Dispersal,
has a population of organisms been in an area for a long time or recently arrived
survival and reproduction
how long the organisms live and how often, how much, when they reproduce
a possible answer to the question is called a
hypothesis
Population
Represents:
- All possible individuals in a group of organisms
- Impossible to measure an entire population
Sample
A subset of a population
- Used to make inferences about the
entire population - How should crayfish be selected?
-randomly
Parameter
Some property of the entire population of interest
- A measurable factor
-mean or SD = descriptive statistics
Statistic
Mean and standard deviation of the
sample
- Estimate of the parameter
For crayfish example:
Population: Crayfish in Aperture Pond
Sample: 50 crayfish from Aperture Pond
Parameter: Mean Weight of crayfish in Aperture Pond
Statistic: Mean Weight of 50 crayfish from Aperture Pond
Replication
More measurements makes a sample more
representative of the population
- Sample size (n) is taken into account when
determining confidence in the statistic - Important to be aware of pseudoreplication
- Need to conduct random samples to avoid
bias
pseudoreplication
where there is only a single replicate per treatment, but subsamples are taken from each area.
Bias
type of error
measurements are consistently wrong
leads to poor accuracy
bias problem 1
Biased sampling
Solution → random sample
bias problem 2
Biased measurements
Solution → calibrate equipment, consistency among observers
Accuracy vs. Precision
- Accuracy
= how close our mean is to the “true” mean - Precision
= how close repeated measurements are to
each other
Standard Error
Quantifies how much confidence we should have in our estimate of the ‘true’ mean of a population
Replication
The more we sample a population the more
likely we are to get closer to the ‘true’ mean
- Increased sample size gives better estimate
of population
Nominal measurement
named categories
allow only counts or frequency data
Ordinal measurements
ranks
Interval or Ratio measurements
interval: can - and + not x and /
(cant measure “no temp)
ratio: there is a physically meaningful zero
-height, weight, length
- Discrete measurement
Only certain values possible
Nominal, ordinal, and interval/ratio data
Continuous measurement
height and weight, any value is possible
Interval/ratio data
Dr. Burg identifies the various species of chickadee found in riparian areas within Lethbridge county (data type P)
Nominal
Dr. McCune counts the number of snowberry shrubs within a quadrat (data type p)
Ratio and discrete
Dr. Hoover studies the internal hive temperature of honeybees (data type P)
Interval and continuous
Animal Sampling Methods
Destructive and invasive sampling
Noninvasive sampling
Ethics are very important!
Destructive and invasive sampling
Trapping/hunting/fishing with retention of catch
Mark/recapture
Blood/bodily fluid sampling
Noninvasive sampling
feathers, hair, molts, feces, road kill, tracks, etc
Trail cams
Ethics
Agencies in place to ensure animal welfare is
considered
abiotic factors
the physical and chemical characteristics of the environment
biotic factors
the influenece of other organisms through competition, predation, ect
microhabitat
a small area which differs somehow from the surrounding habitat.
transect
a line running through the population to be sampled, often along some sort of gradient in the environment
quadrat
easily transportable plot that is laid down on the surface being studied to define a standard sampling area
What is a hypothesis?
Hypothesis = observation + possible explanation/mechanism
- More than one hypothesis can explain an
observation
What is a prediction?
A statement that arises logically from a hypothesis
- Often “if-then” statements
What makes a good hypothesis?
- Has to be testable.
- Must be able to falsify our idea wrong.
- Builds on previous knowledge.
-Should make sense in terms of what we already know
-We always try to build on previous knowledge
-Background - introduction of a research paper
Phenotypic Variation
- Differences in phenotype from one individual to another within a species.
- Environmental factors can play an important
role