Download evolution / taxonomy study guide

EVOLUTION / TAXONOMY STUDY GUIDE
I. Evidence of evolution
A. Similarities in DNA sequences
B. Fossil records
C. Embryonic similarities
1. Pig, fish, mammal = all have gills and tail at some point during their
embryonic development
D. Structures
1. homologous – organisms are similar in structure, but may look
slightly different and or have a different function
a. whale flipper, human arm, bat wing
2. vestigial – organ that is no longer used, but was used at some point
in the organisms ancestry
a. human appendix
3. analogous – organisms structures are different, but have same
function because of similar environmental pressures
a. bird wing and insect wing
II. Theories of evolution
A. Lamarck – acquired characteristics (use and disuse)
1. Was proven wrong
2. Believed that organisms adapt to their environment …BUT thought
it was instant, in that organisms lifetime
3. Changes in the organism’s structure or function was the result of use
or disuse and those changes were passed on to its offspring
a. mice do not use their tails so offspring would be born
without tails
B. Darwin – natural selection (survival of the fittest)
1. Believed that organisms with the traits that are best suited for the
environment are the ones that are going to reproduce and survive
a. species are able to adapt to their environment over time
i. because of genetic variations with in a population
and mutations
b. if species are unable to adapt they will become extinct
2. Speciation can occur when members of population are
geographically separated from each other
III. Classification
A. organisms grouped according to similarities
1. order of classification = taxonomy
a. developed by Linnaeus
Kingdom, Phylum, Class, Order, Family, genus, species
Biggest
&
Broadest
i.
Smallest
&
most unique
the more divisions that an organism has in common, the
more closely related they are
ii. scientific name = genus species = binomial
nomenclature
2. Binomial nomenclature – 2 word scientific name
a. made up of the genus and species of an organism