Field techniques for Biologists Flashcards
(26 cards)
Hazards in fieldwork include
-Adverse Weather conditions
-Difficult terrain
-Problems associated with isolation
-Contact with harmful organisms
Risk assessment involves
Identifying control measures to minimise risk
Control measures include
Appropriate equipment, clothing, footwear and means of communication
Sampling techniques
- point count
- quadrats
- transects
- capture techniques for mobile species
- camera traps for elusive species
- scat sampling also for elusive species
Point count
For avian research, observer recording all individuals seen from a fixed point count location.
Quadrats and transects
Used for plants and other sessile or slow moving organisms
identification of an organism in a sample made using
- Classification guides
- Biological keys
- Analysis of DNA or protein
Organisms can be classified by
Taxonomy and phylogenetics
Taxonomy
Involves the identification and naming of organisms and their classification into groups based on shared characteristics
What’s taxonomy based on
Morphology(structure of organisms)
Phylogenetics
study of the evolutionary history and relationships among individuals/groups of organisms,
Phylogenetics uses traits such as
Morphology, DNA sequences and protein to make inferences about an organisms evolutionary history and create a phylogeny
Divergent Evolution
When a species from a common ancestor evolve differently
Convergent Evolution
When a species that have evolved from different ancestries develop similar structure
Taxonomic groups
Nematodes
Arthropods
Chordates
Nematodes
Round worms: very diverse, many parasitic
Arthropods
Jointed legged invertebrates,
Chordates
Sea squirts and vertebrates such as fish amphibians reptiles reptiles birds and mammals
Model organisms
easily studied or have been well studied
Info from them can be applied to other more difficult species
important model organisms in the advancement of modern biology
- E. coli
- Arabidopsis thaliana
- Nematode C. elegans
- Arthropod Drosphilia melanogaster
- Mice, rats, zebrafish which are chordates
indicator species
presence, absence or abundance of indicator species suggests presence of pollutant or absence of it.
Absence or reduced population suggests..
indicates a species is susceptible to a factor of the environment
Abundance or increased population
indicates its favoured by the conditions
Method of mark and recapture to estimate population size
N=MC/R
N= Population
M= Sample of population captured, marked, and released. Then second sample is captured
C= Number captured in 2nd sample
R= number recaptured in 2nd sample