Objectives:
1) Define
species. 2)
Create a
dichotomou
s key to
classify any
common 6
household
items.
These 2 species might still have the ability to
interbreed.
Is the definition of species hold true and
therefore accurate?
No
Dichotomous Key
Species Defined:
1) Population that can reproduce.
2) Similar physical appearances
The problem with Hybrids
Sometimes a species will become isolated from
each other. The result is the emergence of 2
species.
These 2 species might still have the ability to
interbreed.
Is the definition of species hold true and
therefore accurate?
No
Taxonomists try interpret the evolutionary
history of a species (termed phylogeny) by
comparing physical traits.
Convergent Evolution: similar traits evolve
independently from eachother.
Similar features that evolved through
convergent evolution are termed analogous
traits.
For example, below is a simple dichotomous key.
Bean round
Garbanzo bean
1b.
Bean elliptical or oblong
Go to 2
1a.
A dichotomous key is an identification key that
contains pairs of contrasting descriptions.
These descriptions must be physical and will
assist its reader in the correct classification of
an unknown entity.
2a.
Bean white
White northern
2b.
Bean has dark pigments
Go to 3
3a.
Bean evenly pigmented
Go to 4
3b.
Bean pigmentation mottled
Pinto bean
4a.
Bean black
Black bean
4b.
Bean reddish-brown
Kidney bean
1