Transcript Evidence for Evolution

Evidence for Evolution
Evidence for Evolution
• Fossils
– provide a record of
early life &
evolutionary history
– Currently, the fossil
record is incomplete
(like a jigsaw puzzle w/
missing pieces)
– The more fossils
discovered, the clearer
the evolutionary
picture becomes!
Evidence for Evolution
• Biogeography
–The study of the locations of organisms
around the world
–Organisms in similar
environments have
similar adaptations
despite being on
completely different
continents.
•Ex: Large, flightless birds
Evidence for Evolution
• Anatomy
–the way an organism is put together
–Homologous structures
–Analogous Structures
–Vestigial Structures
Homologous Structures
• Parts with a common evolutionary history
– Ex: Organisms that have the same basic skeleton, bones
are just modified for different functions
– It would be unlikely
for so many animals
to have similar
structures if each
species arose
individually!
Analogous Structures
• Body parts that are similar in function, but
not evolutionary origin
• Ex: Wings of a butterfly & wings of a bird
Vestigial Structures
• Body structure that has no function in
present day organisms, but was probably
useful to an ancestor
• Ex: Eyes on Naked Mole Rats, Appendix in
humans, Wings on ostrich
Evidence for Evolution
• Adaptations: Structural
– Develop over many
generations (ex: claw length,
fur color, etc)
•Mimicry: enables one
species to resemble
another species.
Monarchs and Viceroys
•Camouflage: enables
species to blend in with
their surroundings
Monarch
TOXIC!
Viceroy
TASTY!
Evidence for Evolution
• Adaptations: Physiological
– Changes in an organisms
metabolic processes (occurs
more rapidly)
• Bacteria’s resistance to
antibiotics
• Insects / weeds
resistance to
certain
pesticides
Evidence for Evolution
• Embryological
– similarities between young embryos suggest
evolution from a distant common ancestor
Evidence for Evolution
• Biochemical
– Provides info about
relationships between
individuals and species
– Uses RNA & DNA
sequences to construct
cladograms
(evolutionary
diagrams)