Download 16.2 Applying Darwin`s Ideas

16.2 Applying Darwin’s Ideas
I. Evolution by Natural Selection
A. Individuals with better traits are more likely
survive
B. Natural selection = survival of the fittest
C. Darwin’s theory predicts that over time the
number of better suited individuals will
increase
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D. Steps of Darwin’s Theory
1. Overproduction
2. Variation
3. Selection
4. Adaptation
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E. Selection & Adaptation
1. An adaptation is an inherited trait that
helps individuals survive & reproduce
2. each species becomes adapted to its
environment due to living in it
F. Publication of the theory
1. Darwin’s book On the Origin of Species
by Means of Natural Selection
II. What Darwin Explained
A. Living species evolved from organisms
that lived in the past.
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B. Fossil
1. Traces of organisms that lived in the
past
C. Darwin predicted intermediate forms
between groups of species
D. Conditions that create fossils are so
rare the fossil record will never be
complete
E. Biogeography
1. The study of the locations of
organisms around the world
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2. Sometimes geography separates
populations
a. Over time the two groups may
evolve into different species
F. Developmental Biology
1. Embryology
a. the study of ways that multicellular
organisms develop from embryos
2. Scientists compare embryonic
development of species to look for
similar patterns & structures
a. Shows they have a common
ancestor
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G. Anatomy
1. The study of bodily structure
2. Internal similarities show evidence of
relation
a. ex- bone structure
3. homologous structures
a. similar structure in two or more
species showing a common
ancestor
H. Biochemistry
1. Comparing DNA or amino acids
between species shows relation
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2. Organisms that have fewer differences
are more closely related
III. Evaluating Darwin’s Ideas
A. Strengths
1. evidence of evolution
a. gathered so much data
2. mechanism for evolution
a. presented a logical & testable
mechanism for process of evolution
3. recognition that variation is important
a. serves as the start of evolution
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B. Weaknesses
1. Darwin knew very little about genetics
2. Mendel’s ideas that supported his work
were not widely published until 1900.
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