Transcript Dichotomous keys/taxonomy ppt Dichotomous key ppt

Taxonomy
Taxonomy
How
organisms are classified
and named
Why classify?
Gives us information about
Similarities
Differences
Evolutionary history
 It
is important to note that scientists
do not always agree when
classifying organisms
 As more information becomes
available, especially DNA
evidence, classification schemes
change.
Why name?
All are “correct”
Cougar
Mountain
Puma
Panther
lion
Scientists call her
Puma
concolor
 To
better understand the unity and
diversity of all organisms, scientists use
phylogenetics.
A
way to evaluate and categorize
observable heritable traits to determine
the evolutionary history (phylogeny) of a
species or group of species
Species
A
population that can
interbreed and produce viable,
fertile offspring
Dichotomous key
 One
tool that scientists use to categorize
or classify living things based on physical
characteristics.
 “di”= two
 “tom”= slice or cut
 The goal is is identify organisms, usually
species, by their unique visible
characteristics.
 Often used in field guides
Characteristics used in
dichotomous keys must
 Be
readily measured or observed
 Be mutually exclusive, no overlap
 NOT be subjective or inferred, i.e.
words like short, strong, pretty are
not acceptable
Let’s
try to create one