Transcript CH05_SU04

CHAPTER 5: EVOLUTION AND BIODIVERSITY:
ORIGINS, NICHES AND ADAPTATION
Figure 5-1
Page 92
Slide 1
Chemical Evolution
(1 billion years)
Formation
of the
earth’s
early
crust and
atmosphere
Small
organic
molecules
form in
the seas
Large
organic
molecules
(biopolymers)
form in
the seas
First
protocells
form in
the seas
Biological Evolution
(3.7 billion years)
Single-cell
prokaryotes
form in
the seas
© 2004 Brooks/Cole – Thomson Learning
Single-cell
eukaryotes
form in
the seas
Variety of
multicellular
organisms
form, first
in the seas
and later
on land
Figure 5-2
Page 93
Slide 2
Stanley Miller's experiment animation.
Click to view
animation.
Animation
Slide 3
Modern humans
(Homo sapiens)
appear about
2 seconds
before midnight
Age of
reptiles
Insects and
amphibians
invade the land
Age of
mammals
Recorded human
history begins
1/4 second
before midnight
midnight
Origin of life
(3.6–3.8 billion
years ago)
Plants
invade the
land
First fossil
record of
animals
Plants
begin
invading
land
noon
Evolution and
expansion of life
Figure 5-3
Page 94
Slide 4
Figure 5-4
Page 96
Slide 5
Example of directional selection animation.
Click to view
animation.
Animation
Slide 6
Figure 4-5
Page 68
Slide 7
Snail coloration
best adapted
to conditions
Average
Natural
selection
Number of individuals
Number of individuals
Directional Natural Selection
New average
Coloration of snails
Previous
average
Average shifts
Coloration of snails
Proportion of light-colored
snails in population increases
Figure 5-5 (1)
Page 97
Slide 8
Lower limit
of tolerance
Few
organisms
Abundance of organisms
Few
organisms
No
organisms
Population Size
No
organisms
Upper limit
of tolerance
Zone of
Zone of
intolerance physiological stress
Low
Optimum range
Temperature
Zone of
Zone of
physiological stress intolerance
High
Figure 4-13
Page 72
Slide 9
Light snails
eliminated
Dark snails
eliminated
Natural
selection
Number of individuals
Number of individuals
Stabilizing Natural Selection
Snails with
extreme
coloration are
eliminated
Coloration of snails
Coloration of snails
Average remains the same,
but the number of individuals with
intermediate coloration increases
Figure 5-5 (2)
Page 97
Slide 10
Intermediate-colored snails
are selected against
Light
coloration
is favored
Dark
coloration
is favored
Natural
selection
Number of individuals
Number of individuals
Diversifying Natural Selection
Snails with light and dark
colors dominate
Coloration of snails
Coloration of snails
Number of individuals
with light and dark coloration
increases, and the number with
intermediate coloration decreases
Figure 5-5 (3)
Page 97
Slide 11
Number of individuals
Niche
separation
Generalist species
with a narrow niche
Niche
breadth
Generalist species
with a broad niche
Region of
niche overlap
Resource use
Figure 5-6
Page 98
Slide 12
Herring gull is a
tireless scavenger
Black skimmer
seizes small fish
at water surface
Flamingo
feeds on
minute
organisms
in mud
Brown pelican dives for fish,
which it locates from the air
Scaup and other
Avocet sweeps bill through
diving ducks feed on
mud and surface water in
mollusks, crustaceans,
search of small crustaceans,
and aquatic vegetation
insects, and seeds
Dowitcher probes deeply
into mud in search of
snails, marine worms,
and small crustaceans
Oystercatcher feeds on
clams, mussels, and
Louisiana heron wades into other shellfish into which
water to seize small fish
it pries its narrow beak
Ruddy turnstone
searches
under shells and
pebbles for small
invertebrates
Knot (a sandpiper) picks up
worms and small crustaceans
left by receding tide
Piping plover feeds
on insects and tiny
crustaceans on
sandy beaches
Figure 5-7
Page 100
Slide 13
Northern population
Arctic Fox
Early fox
population
Spreads
northward
and
southward
and
separates
Adapted to cold
through heavier
fur, short ears,
short legs, short
nose. White fur
matches snow
for camouflage.
Different environmental
conditions lead to different
selective pressures and evolution
into two different species.
Southern population
Gray Fox
Adapted to heat
through lightweight
fur and long ears,
legs, and nose, which
give off more heat.
Stepped Art
Figure 5-8
Page 100
Slide 14
LAURASIA
120° 80°
40°
80°
120°
120° 80°
80°
120°
GONDWANALAND
135 million years ago
225 million years ago
NORTH AMERICA
EURASIA
AFRICA
120° 80°
SOUTH
AMERICA
INDIA
MADAGASCAR
120°
120°
0°
40°
120°
AUSTRALIA
ANTARCTICA
65 million years ago
Present
Figure 5-9
Page 101
Slide 15
Slide 16
Slide 17
Stabilizing selection animation.
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animation.
Animation
Slide 18
Disruptive selection animation.
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animation.
Animation
Slide 19
Evolutionary tree of life animation.
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animation.
Animation
Slide 20
Evolutionary tree diagrams interaction.
Click to view
animation.
Animation
Slide 21