Download Evidence of Evolution Notes

Evidence of Evolution Notes
Mrs. Sands
1. Fossil Record
Fossils are ________________________ evidence
They are typically found in __________________________________ rock
Fossils provide a ______________________ of species that lived long ago.
Some fossils are _______________________ to current ones!
Example:
Some species go ________________________ for millions of years!
Example:
Fossil Record:
A.
“__________________________” parts don’t fossilize (like tissue or organs)
B. Specific ____________________________are needed to form fossils (wet
C. Hundreds of ____________________________________ fossils found
 Two major classes of traits while studying transitional fossils:
–
_________________________traits: newly evolved _____________________found on the
organism.
–
___________________________traits: more ____________________________features that
appear in ancestor forms.
2. Homologous Structures:
________________________________ similar structures
Shows evidence of ___________________________________________ origin
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 Homologous Structures
Organism’s body parts are more likely to be
_____________________________of ancestral body parts
than they are to be entirely __________________ features.
They vary in function but are similar in shape and
construction.
Ex. Birds ________________, reptiles _______________,
humans can manipulate objects, walk, run, swim, etc.
 Analogous Structures:
Can be used for _________________________________ and can be
superficially similar in construction but are
___________________________ from a common ancestor.
Example: Insects and Birds
3.Embryology:
Looks at __________________________ in embryos
 ______________________ – early, pre-birth stage
of an organism’s development.
 Vertebrate embryos exhibit
_________________________________ during
certain phases of development.
4. Compararative Biochemistry:
Organisms have ____________________ DNA, genes and enzymes
 The more closely related the species are the _____________________________ of amino acid
sequences they will share.
 Ex. Chimpanzees and Humans share ______________________ sequences!
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5. Vestigial Structures:
Structures that are ______________________________
and most no longer have a function
Examples:
 Appendix is of little to no use in humans and some apes;
aids in digestion
 Coccyx bone- remnant of our tail bone.
 Kiwi wings: too small to be any use in
_________________________
Speciation:
_____________________________________ of new species
The organisms become become ____________________________________ different
Species is a ______________ of organisms that can ___________________ & produce ______________offspring
Infertile Species
Horse + Donkey = Mule: why? The horse has ______ chromosomes and the donkey has ________
chromosomes.
Male lion + female tiger = Liger
Ti-Ligers (Female ligers who have bred with male tigers)
Li-Ligers (Female ligers who have bred with male lions).
Species Loop Hole
Not a ______________________________definition
Used for ___________________________________________
Some different species _______________________ produce __________________________ offspring
Examples:
Grizzly Bear & Polar Bear known as the “________________________” or the “_________________________”
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Rate of Speciation
Most scientists believe that evolution occurs at a ________________rate which is known as
_____________________________ and a great deal of evidence favors this theory.
However, the ___________________ record contains instances of ________________________ changes
where evolution occurs at _____________________________ rates which is known as
___________________________________________________
Cause of Speciation
1. Geographic Barriers like _________________________ and __________________________.
2. Environment Changes like _______________________ and _________________________________.
3. Reproductive Isolation
Examples:
–
mating at _____________________________ times
–
Birds mating with others who sing a __________________________________ song.
Patterns of Evolution:
__________________________radiation (divergent evolution) occurs in a ________________________ short
time where one species gives rise to many ___________________________ usually following a mass
__________________________________.
Example: Extinction of dinosaurs likely produced the diversity of mammals visible today through
adaptive radiation.
Coevolution: evolution of one species ____________________the ______________________of another
species.
Examples: comet orchids and moths that pollinate them.
Bumble bees and flowers
Hummingbirds and red flowers
Convergent evolution: unrelated species evolve ___________________ traits even though they live in
______________________________parts of the world.
Organisms are under same ________________________________________ pressures
Examples: mara and rabbit
Insects and bird or bat wings
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