Interpreting cladograms
How is a matrix to form a cladogram made?
amino acid/ sequence differences in proteins
or can be done by characteristics
The fewer differences between species…
The closer together they should be in the cladogram
you probably won’t get asked to draw a whole cladogram from scratch but you
might have to interpret it or add some species
What is the root?
the original common ancestor that the other organisms have evolved from
What is a node?
branching point where species diverge (hypothetical common ancestor)
What is a terminal branch?
final branch ending in a taxon (pl. taxa), usually an extant (still going) species
if extinct species are included, the cladogram might be more based on
morphology
we assume that mutations in base sequences occur at a constant rate
What is the Woesian classification system?
prokaryota (including spirochetes, green bacteria)
archaea (including methanogens, halophiles)
eukaryota
Interpreting cladograms 1
, Monitoring organisms
What is a population?
group of organisms living in the same area at the same time
normally breed
can distinguish different populations of species using reproductive isolation
What does sampling do?
estimate population sizes to provide a reliable representation of a
population
have to be random
Give 2 examples of sampling methods
quadrats
transects
Give 1 limitation of these methods
organisms must be sessile (not motile)
Describe the capture-mark-release-recapture method for motile species.
1. capture animals eg using pitfall traps
2. count + mark in an inconspicuous way
Interpreting cladograms 2
How is a matrix to form a cladogram made?
amino acid/ sequence differences in proteins
or can be done by characteristics
The fewer differences between species…
The closer together they should be in the cladogram
you probably won’t get asked to draw a whole cladogram from scratch but you
might have to interpret it or add some species
What is the root?
the original common ancestor that the other organisms have evolved from
What is a node?
branching point where species diverge (hypothetical common ancestor)
What is a terminal branch?
final branch ending in a taxon (pl. taxa), usually an extant (still going) species
if extinct species are included, the cladogram might be more based on
morphology
we assume that mutations in base sequences occur at a constant rate
What is the Woesian classification system?
prokaryota (including spirochetes, green bacteria)
archaea (including methanogens, halophiles)
eukaryota
Interpreting cladograms 1
, Monitoring organisms
What is a population?
group of organisms living in the same area at the same time
normally breed
can distinguish different populations of species using reproductive isolation
What does sampling do?
estimate population sizes to provide a reliable representation of a
population
have to be random
Give 2 examples of sampling methods
quadrats
transects
Give 1 limitation of these methods
organisms must be sessile (not motile)
Describe the capture-mark-release-recapture method for motile species.
1. capture animals eg using pitfall traps
2. count + mark in an inconspicuous way
Interpreting cladograms 2
