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2/17/2017
Endless Forms Most Beautiful
Challenging traditional views
 Charles Darwin and Origin of Species
 Evolution
1809
Lamarck publishes his
hypothesis of evolution.
1809
Lamarck publishes his
hypothesis of evolution.
1798
Malthus publishes
“Essay on the Principle
of Population.”
Sketch of a flying
frog by Wallace
1812
Cuvier publishes his
extensive studies of
vertebrate fossils.
1795
Hutton proposes
his principle of
gradualism.
1830
Lyell publishes
Principles of Geology.
1858
While studying species in the
Malay Archipelago, Wallace
(shown above in 1848) sends
Darwin his hypothesis of
natural selection.
1790
1809
Charles Darwin
is born.
1831–1836
Darwin travels
around the world
on HMS Beagle.
1870
1859
On the Origin of
Species is published.
1844
Darwin writes his
essay on descent
with modification.
1798
Malthus publishes
“Essay on the Principle
of Population.”
1795
Hutton proposes
his principle of
gradualism.
Marine iguana
in the
Galápagos
Islands
1790
1809
Charles Darwin is born.
Figure 22.2b
Scala Naturae and Classification of Species
1830
Lyell publishes
Principles of Geology.
1831–1836
Darwin travels
around the world
on HMS Beagle.
1812
Cuvier publishes his
extensive studies of
vertebrate fossils.
1858
While studying species in the
Malay Archipelago, Wallace
sends Darwin his hypothesis
of natural selection.
1870
1859
On the Origin of
Species is published.
 Aristotle
 Carolus Linnaeus
1844
Darwin writes his
essay on descent
with modification.
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Ideas About Change over Time
 Fossils
Sedimentary rock
layers (strata)
 Strata
Younger stratum
with more recent
fossils
Older stratum
with older fossils
 Georges Cuvier
Lamarck’s Hypothesis of Evolution
 James Hutton and Charles Lyell
Descent with modification by natural
selection
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Figure 22.5a
Darwin’s Focus on Adaptation
Great
Britain
EUROPE
NORTH
AMERICA
ATLANTIC
OCEAN
AFRICA
SOUTH
AMERICA
Chile
PACIFIC
OCEAN
Equator
PACIFIC
OCEAN
Malay
Archipelago
Brazil
AUSTRALIA
Cape of
Good Hope
Argentina
Tasmania
Cape Horn
New
Zealand
 1844 essay
(a) Cactus-eater
(b) Insect-eater
(c) Seed-eater
The Origin of Species
Descent with Modification
 three broad observations
 The unity of life
 The diversity of life
 The match between organisms and their
environment
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Figure 22.8
Figure 22.7
Hyracoidea
(Hyraxes)
Sirenia
(Manatees and relatives)
†Moeritherium
†Barytherium
†Deinotherium
†Mammut
†Platybelodon
†Stegodon
†Mammuthus
Elephas maximus (Asia)
Loxodonta africana (Africa)
Loxodonta cyclotis (Africa)
60
34
5.5 2104 0
24
Millions of years ago
Years ago
Hyracoidea
(Hyraxes)
†Platybelodon
Sirenia
(Manatees and relatives)
†Stegodon
†Moeritherium
†Mammuthus
†Barytherium
†Deinotherium
Elephas maximus (Asia)
Loxodonta africana (Africa)
†Mammut
Loxodonta cyclotis (Africa)
60
60
34
24
Millions of years ago
34
5.5 2104 0
24
5.5 2104 0
Millions of years ago
Years ago
Years ago
Artificial Selection, Natural Selection, and
Adaptation
Figure 22.9
Cabbage
Selection
for apical
(tip) bud
Brussels
sprouts
Broccoli
Selection for
axillary (side)
buds
Selection for
flowers and stems
Selection
for stems
Selection
for leaves
Kale
Wild mustard
Kohlrabi
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 Observation #1: Members of a population often
vary in their inherited traits
 Inference #1: Individuals whose inherited traits
give them a higher probability of surviving and
reproducing in a given environment tend to leave
more offspring than other individuals
 Observation #2: All species can produce more
offspring than the environment can support, and
many of these offspring fail to survive and
reproduce
 Inference #2: This unequal ability of individuals to
survive and reproduce will lead to the
accumulation of favorable traits in the population
over generations
Natural Selection: A Summary
1.
2.
A flower mantid in Malaysia
A flower-eyed mantid in
South Africa
3.
A leaf mantid in Borneo
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Evidence
 Populations, not individuals
Figure 22.13
Direct Observations
Results
 Responding to introduced plants
10
Number of individuals
Field Study
 Antibiotic resistance
Soapberry bug with beak
inserted in balloon vine
fruit
Figure 22.14a 2,750,000
1
250,000 base pairs
8
6
4
On native species,
balloon vine
(southern Florida)
Beak
2
0
Average for museum specimens
10
On introduced
species,
goldenrain tree
(central Florida)
8
6
4
2
0
6
7
8
9
Beak length (mm)
10
11
Figure 22.14b
Chromosome map
of S. aureus clone USA300
500,000
Key to adaptations
2,250,000
2,000,000
Methicillin resistance
Ability to colonize hosts
Increased disease severity
Increased gene exchange
(within species) and
toxin production
1,750,000
1,500,000
750,000
1,000,000
Annual hospital admissions
with MRSA (thousands)
400
2,500,000
350
300
250
200
150
100
50
0
’93 ’94 ’95 ’96 ’97 ’98 ’99 ’00 ’01 ’02 ’03 ’04 ’05
Year
1,250,000
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Figure 22.UN04
 New traits?
Homology
Figure 22.15
Humerus
Radius
Ulna
Carpals
Metacarpals
Phalanges
Human
 Comparative embryology
Cat
Whale
Bat
Figure 22.16
Pharyngeal
arches
Post-anal
tail
Chick embryo (LM)
Human embryo
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 Vestigial structures
Evolutionary Trees
Convergent Evolution
Branch point
Lungfishes
 Analogous Structure
Amnion
Lizards
and snakes
3
4
Homologous
characteristic
Crocodiles
Ostriches
Feathers
Birds
5
6
Hawks and
other birds
Figure 22.18
Sugar
glider
Amniotes
Mammals
2
Digit-bearing
limbs
Tetrapods
Amphibians
1
The Fossil Record
NORTH
AMERICA
AUSTRALIA
Flying squirrel
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Figure 22.19
 Fossils can document important transitions
Most mammals
Cetaceans and even-toed ungulates
(a) Canis (dog)
(b) Pakicetus
(c) Sus (pig)
(d) Odocoileus (deer)
Figure 22.20
Biogeography
Other even-toed
ungulates
 Biogeography
Hippopotamuses
†Pakicetus
 Pangaea
†Rodhocetus
†Dorudon
Common
ancestor
of cetaceans
0
50
40
30
60
Millions of years ago
 Endemic species
Living
cetaceans
Key
Pelvis
Femur
Tibia
Foot
What Is Theoretical About Darwin’s View of
Life?
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