Download Evolution - Ector County ISD.

Evolution
Unit 8 review
Natural
selection
What causes
variations within a
population?
Variations are the
differences within a
population.
Variations are
caused by
mutations, random
mating, and
migration
Natural
Selection
What is
differential
reproductive
success?
Differential
reproductive
success means that
individuals do not
have equal chances
of reproducing.
Only those who can
survive will
reproduce.
Natural
Selection
How do these
things result in
Natural Selection?
Because of
reproductive success,
certain traits will be
more suitable for
survival, therefore, will
be passed on to the
next generation. This is
natural selection
What is speciation? What causes
speciation?
 Speciation is the formation
of a new species through
the process of evolution
 Causes
 Geographical isolation
 Gene flow
immigration
emigration
 Mutations
deletion
Insertion
substitution
duplication
What caused the speciation of the
finches on the Galapogos Islands?
Geographical/reproductive isolation
Different landscapes and available foodAdaptations
What came first?
 Eukaryotic cell
 Prokaryotic cell
 Simple organic molecules, i.e amino acids
 Biomolecules, i.e Proteins
 Answer:
1. Simple organic molecules, i.e amino acids
2. Biomolecules, i.e Proteins
3. Prokaryotic cell
4. Eukaryotic cell
Endosymbiotic Theory
coevolution
Evidence of Evolution (common
ancestor)
Fossil record
Homologies
 Anatomical
Example
 whale flipper & bat wing
 Human arm & lion leg
 Analogous structures do not show common ancestory.
Example:
Bee wings and bird wings
spider legs & dog legs
Molecular homologies
Similarities in the DNA, proteins, amino acid sequence