Download Chapter 24: Molecular and Genomic Evolution

Chapter 24: Molecular and Genomic Evolution
CHAPTER 24
Molecular and Genomic
Evolution
Chapter 24: Molecular and Genomic Evolution
Chapter 24: Molecular and
Genomic Evolution
What Is Molecular Evolution?
Determining and Comparing the Structure of
Macromolecules
Where Do New Genes Come From?
How Do Proteins Acquire New Functions?
Chapter 24: Molecular and Genomic Evolution
Chapter 24: Molecular and
Genomic Evolution
Genome Organization and Evolution
Using Biological Molecules to Reconstruct
Phylogenetic Trees
Molecular Studies of Human Evolution
Chapter 24: Molecular and Genomic Evolution
What Is Molecular Evolution?
• Molecular evolution differs from phenotypic
evolution in that mutations and genetic drift
are much more important determinants of
molecular evolution.
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Chapter 24: Molecular and Genomic Evolution
What Is Molecular Evolution?
• The goals of molecular evolution studies are
to determine patterns of evolutionary
change in organisms’ molecules, determine
the processes that caused the changes, and
use those insights to solve other biological
problems.
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Chapter 24: Molecular and Genomic Evolution
What Is Molecular Evolution?
• Neutral alleles are fixed slowly, whereas
advantageous and disadvantageous alleles
are fixed rapidly.
Review Figure 24.1
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Chapter 24: Molecular and Genomic Evolution
Figure 24.1
Figure 24.1
figure 24-01.jpg
Chapter 24: Molecular and Genomic Evolution
Determining and Comparing the
Structure of Macromolecules
• The polymerase chain reaction method
allows biologists to determine the nucleotide
base sequences of organisms from their
fossilized remains.
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Chapter 24: Molecular and Genomic Evolution
Determining and Comparing the
Structure of Macromolecules
• Biological molecules can be compared by
aligning their sequences.
Review Figure 24.3
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Chapter 24: Molecular and Genomic Evolution
figure 24-03.jpg
Figure 24.3
Figure 24.3
Chapter 24: Molecular and Genomic Evolution
Determining and Comparing the
Structure of Macromolecules
• Changes evolve slowly in regions of
functionally significant molecules,
• but more rapidly in regions where base
substitutions do not affect molecule
functioning.
Review Figures 24.4
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Chapter 24: Molecular and Genomic Evolution
Figure 24.4
Figure 24.4
figure 24-04.jpg
Chapter 24: Molecular and Genomic Evolution
Determining and Comparing the
Structure of Macromolecules
• Rates of amino acid substitutions in some
molecules are relatively constant over
evolutionary time.
Review Figure 24.6
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Chapter 24: Molecular and Genomic Evolution
Figure 24.6
Figure 24.6
figure 24-06.jpg
Chapter 24: Molecular and Genomic Evolution
Where Do New Genes Come
From?
• Most new genes arise from gene
duplication.
• The most important types are genome
(polyploidy) and domain duplication.
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Chapter 24: Molecular and Genomic Evolution
Where Do New Genes Come
From?
• Globin diversity evolved via gene
duplication.
Review Figure 24.7
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Chapter 24: Molecular and Genomic Evolution
Figure 24.7
Figure 24.7
figure 24-07.jpg
Chapter 24: Molecular and Genomic Evolution
Where Do New Genes Come
From?
• Groups of genes aligned in the same order
on chromosomes of distantly related species
are likely to be homologs of one another.
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Chapter 24: Molecular and Genomic Evolution
How Do Proteins Acquire
New Functions?
• Changes in molecule function may result
from gene duplication if one gene retains
the original function and the other evolves a
new one.
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Chapter 24: Molecular and Genomic Evolution
How Do Proteins Acquire
New Functions?
• Homeotic genes have acquired varied
functions in development.
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Chapter 24: Molecular and Genomic Evolution
Genome Organization and
Evolution
• The genome sizes of organisms vary more than a
hundredfold, but the amount of coding DNA varies
much less.
• In general, eukaryotes have more coding DNA than
do prokaryotes;
• Vascular plants and invertebrate animals have more
coding DNA than do single-celled organisms;
• Vertebrates have more coding DNA than do
invertebrates.
Review Figures 24.9, 24.10
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Chapter 24: Molecular and Genomic Evolution
Figure 24.9
Figure 24.9
figure 24-09.jpg
Chapter 24: Molecular and Genomic Evolution
Figure 24.10
Figure 24.10
figure 24-10.jpg
Chapter 24: Molecular and Genomic Evolution
Using Biological Molecules to
Reconstruct Phylogenetic Trees
• Biological molecules can be used to infer
phylogenetic relationships among
organisms.
• For ancient splits and phylogenies of
prokaryotes, molecular data are the only
source of information about phylogenetic
relationships.
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Chapter 24: Molecular and Genomic Evolution
Using Biological Molecules to
Reconstruct Phylogenetic Trees
• Molecules that have evolved slowly are
useful for determining ancient lineage splits.
• Those that have evolved rapidly are useful
for determining recent splits.
Review Figure 24.11
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Chapter 24: Molecular and Genomic Evolution
Figure 24.11
Figure 24.11
figure 24-11.jpg
Chapter 24: Molecular and Genomic Evolution
Molecular Studies of Human
Evolution
• Comparisons of mtDNA from more than 100
ethnically distinct modern human
populations strongly suggest that they all
shared a common African ancestor no more
than 200,000 years ago.
Review Figure 24.12
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Chapter 24: Molecular and Genomic Evolution
Figure 24.12
Figure 24.12
figure 24-12.jpg