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Climate Change and Biodiversity:
Impacts Lecture I
Alpine Summer School 2008
“Interaction and Coevolution of Climate and Biosphere”
Camille Parmesan
Integrative Biology, University of Texas at Austin
1
Outlines of 2 Lectures
• Impacts I
(Tuesday)
– Attribution via scientific inference
– Observed species’ range shifts
– Conservation implications
• Impacts II
–
–
–
–
(Wednesday)
Observed phenological shifts
Consequences of phenological changes
Observed evolution and limits to adaptation
Implications of climate change for human health
2
Intergovernmental Panel on Climate Change
Attribution question
Causal link between biological changes and
anthropogenic climate change?
Impacts question
Are changes negative, neutral or beneficial?
Proportion of biodiversity affected at given point?
Vulnerability question
Which species most at risk?
Which regions most sensitive?
Effectiveness of reserve system?
3
Linkages Among Environmental Issues
Ozone Depletion
Climate Change
Habitat Loss
Sulfate Aerosols
Desertification
Biodiversity Impacts
Water
Nitrogen inputs
Air pollution
Biological Problems with Individual Studies
• Multiple anthropogenic forces (confounded)
•Climate change
•Land use change
•Habitat loss (urbanization, agriculture)
•Increases in N, P, C, uv
• Positive publishing bias
• High yearly variance - difficult to find trends
• Variable quality (sampling, missing data, spatial and
temporal scales)
• Most good datasets are short term (20 yr) & local scale
(generality?)
5
Hypothetical
Species’
Range Map
Extrapolation of species range shift from
single study sites is error prone
Parmesan 1999, 2001a,b, 2004, 2005 6
ATTRIBUTION
Causal Links to Climate Change are from
scientific inference, not direct experimentation
•
Correlational Patterns
– Long-term patterns --- Observed biotic changes match climate change
trends in direction and magnitude
– “natural experiments” --- empirical demonstrations of biotic
responses to extreme weather events and climate
years
•
But, causal mechanism inferred from experiments
– Field Manipulations of temperature and precipitation
– Laboratory Experiments on thermal and desiccation
tolerances
Edith’s checkerspot butterfly range has
shifted northward 92 km and upward
124 m during the 20th c.
Most extinctions in south and
at low elevations
Historical records 1860-1980
Census 1993-1996
green = present
purple = extinct
8
Parmesan Nature, 1996
Extinction Clines across range of E. editha
50
40
40
30
30
20
20
10
0
n=
15
10
74
36
10
N
Latitudinal Bands
16
0
n=
42
20
23
37
29
3 45 0
50
2 40 0
60
1 80 0
60
12 0 0
70
60 0
70
0
% Popu la tion s
Ex tinc t
80
Elevational Band (m)
From: Parmesan, C (1996)
Nature
382:765-766
9
Elevation Extinct Present
< 2400 m
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▲
≥ 2400 m
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100
Results of 19931996 census by
elevation
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10
Lighter Snowpack below 8,000 ft has increased
Probability of False Spring Events
Photo removed
11
Johnson et al. 2000
Climatic Connections
•
0.7º C warming over Western USA → climatic shift of
105 km North & 105 m up
(Karl et al. 1996)
E. editha: mean location shifted
92 km North & 124 m up
(Parmesan 1996)
•
Both snowpack & E. editha extinction trends
shift at 2400 m:
% Δ snow/50 yrs
–
Below 2400 m
–
Above 2400 m
% extinctions
14 % less snowpack ; melt 7 d earlier
8 % more snowpack ; no Δ melt
46 %
14 %
(T. Johnson, 1998)
ATTRIBUTION
Example: Edith’s Checkerspot butterfly
• Correlational Patterns
– Long-term patterns --- range shift matches temperature
isotherm shift and matches patterns of snowpack dynamics
(Parmesan 1996, Karl et al. 1996, Johnson 1998)
– “natural experiments” --- below 2400 m, population
extinctions occur in drought years
• > 20 populations across California over 40 years of censusing
(Singer & Ehrlich 1979, Singer & Thomas 1996)
• Field Manipulations
• Laboratory Experiments
13
Confounding Factors
•
•
•
•
•
•
Genetic diversity
Age of population
Population size
Population isolation
Topography
Human influences
– Habitat degradation
– Secondary effects of urbanization
• Resource use
– - influences of host plant genus
14
Confounding Factors
• NO - Genetic diversity not different in populations that
went extinct compared to those that didn’t
• NO - Age of population (record)
• NO - Population size (habitat size)
• NO - Population isolation
• NOT STRONGLY - Topography
• NO - Human influences
• Habitat degradation
• Secondary effects of urbanization
• YES - Resource use
– host plant genus DOES affect likelihood of
extinction, but not responsible for range shift
Climate and E. editha : Direct field measures
• Observed natural population extinctions caused by single extreme climatic
events (> 20 populations over 40 years)
• Temporal & spatial variation of climate strongly correlated with
population dynamics across species range
– Intensive study of 2 metapopulations (20 & 40 yrs), spotty study on >
15 other populations (much of sp. range)
• Yearly temp./precip. variability ➔ host density and
phenology (senescence) ➔ Offspring starvation
• North and South slopes (macro & micro landscape)
˛
temp./water ➔ local dynamics host/larvae
• Habitat patch types ˛ patch temp/water ➔ flight
seasonality ➔ independent dynamics ➔ colonization
16
Climate and E. editha : Experiments
Manipulations of larvae into different thermal environments in the
field
• 4 independent studies/multiple populations
• Relative phenology of larvae and host plant:
• strongly affected by thermal regime
• crucial determinant of female fitness
• 2-3 three day shortening of host lifespan (earlier
senescence) can increase %larval starvation
from “normal” 98% to 100%
17
ATTRIBUTION by INFERENCE
Example: Euphydras editha butterfly
• Correlational Patterns - YES
– Long-term patterns (100 years) --- range shift matches temperature isotherm
shift and matches patterns of snowpack dynamics
(Parmesan 1996, Karl et al. 1996, Johnson 1998)
– “natural experiments” (40 years) --- below 2400 m, population extinctions
occur in drought years and following false springs (light snowpack). Above
2400m, booms occur with heavy snowpack
(Singer & Ehrlich 1979, Singer & Thomas 1996, McLaughlin et al. 2002)
• Field Manipulations - YES
– manipulating thermal environment (slope aspect, habitat type) affects
larval growth rates, pupal times, synchrony with host plant, and
colonization success
(Singer 1972, Weiss et al. 1988, 1993,, Boughton 1999)
• Laboratory Experiments - YES
–
temperature increases larval growth rates
(Weiss et al 1988, Hellmann 2000)
18
An Unbiased Estimate of Species’
Responses to Climate Change
• Minimize confounding factors
•Studies in relatively undisturbed
environments
• > 20 years data (avg. 44 years, max 140 years)
• Publishing bias: only include multi-species
studies
• Estimate proportion of species responding
• Unique biological fingerprint?
• Climate change only plausible driver
19
Root et al. 2003
Global Phenological
Trends
n = 109
??
5.2 d/dec advance
(mostly northern
temperate zone)
Count
50
45
Parmesan & Yohe 2003
40
n = 172
35
2.3 d/dec advance
30
25
20
15
10
5
0
-35
-30
-25
-20
-15
-10
days / decade: earlier
-5
0
5
20
later
Whole Range Study of 57
Species Across Europe
Photo removed
21
Parmesan et al. Nature 1999
More Statistical Problems
• Sampling methods have changed at various times
- e.g. Moth bait changing in mid-1950s led to
dramatic increase in recorded species diversity
• Sampling intensity has increased through time
- increases in density of sampling points could
lead to false estimate of range expansion
22
Checquered skipper
Photo removed
23
65 % of 52 species had colonized northward at
northern range boundary
(30-200 km, 30-100 years, 0.6° C)
Purple emperor (Apatura iris)
Pu r p l e
Em p ero r
20 ° E
Fi nl a nd
(A pa t ur a
i r is )
60°
Photo removed
Esto n ia
N
58°
Sw e de n
De n m ar k
Blue arrows: 1900 to 1999
Parmesan et al. Nature 1999;
Unpublished Ryrholm, Kaila & Kullberg
Green arrows: 2000 to
2003 >100 km
expansion
24
22 % of 40 species contracted at southern
range boundaries
* 1 species range reduction
Parmesan et al. Nature 1999
Heode s
t it yr us
20 ° E
60°
Sooty copper
(Heodes tityrus)
Invasion of Estonia (green)
1998 - 1st record
1999 - breeding populations
2004 - spread to Baltic Sea
Fi nl a nd
Es t o ni a
N
Sw e de n
56°
Fra n c e
42°
Spa i n
40°
Ca t al o nia
4° E
Extinction in Catalonia (light grey)
1930s - common nr Barcelona
1990s - southern-most population
25
100 km N in Pyrenees
Summary of Distributional Changes in 57
Species of European Butterflies
(Parmesan et al. Nature '99)
Going N Going S
Northern Edges :
Binomial test
Stable
65 %
2%
P << .001
34 %
22 %
5%
P < .04
72 %
63 %
6%
P << .001
29 %
(52 species)
Southern Edges :
(40 species)
N & S Edges same species :
(35 species)
26
Summary of Distributional Changes in 57
Species of European Butterflies
(Parmesan et al. Nature '99)
Going N Stable
Northern Edges :
Going S
Binomial test
66 %
34 %
0%
P << .001
22 %
72 %
5%
P < .04
66 %
29 %
3%
P << .001
(52 species)
Southern Edges :
(40 species)
N & S Edges same species :
(35 species)
27
Changes in Northern / Upper Range
Limits among Temperate Species
100
80
60
north /
upslope
mean
6.1 km-m
/decade
40
20
0
south /
downslope
-20
-40
-60
-80
-100
Observations
bird
butterfly
herb
taxa ns different
Parmesan & Yohe, Nature
28 2003
Observed changes
studies published up to July 2002
Nminimum
(#species or
functional
groups)
Changed in
direction
predicted
(n)
Changed in
opposite to
prediction
(n)
Stable
(n)
trees, shrubs, herbs
birds, frogs
butterflies
242
43 %
6%
52 %
at poleward range edges
(high elevation limits)
trees, herbs,
mammals, birds
butterflies
150
63 %
13 %
15 %
at equatorial range edges
(low elevation limits)
birds, butterflies
186
13 %
9%
77 %
cold-adapted
shrubs, herbs,
reptiles, amphibeans,
fish, marine
zooplankton &
invertebrates
141
27 %
1%
71 %
115
85 %
11 %
3%
Type of change
taxa studied
Phenological
Distributional
changes
(expansions &
contractions along
range edges)
community
changes
(local abundance
changes)
(Parmesan & Yohe 2003)
warm-adapted
No
prediction
(n)
10 %
1%
Out of 1570 species, about half were stable
29
Estimated: More than Half of Wild Species have Responded
to 20th c. Climate Change
(>1500 species / species groups)
Changed as
predicted
(n)
Changed opposite
to prediction
(n)
P
87 %
13 %
< .1 x10-12
Distributional changes:
At poleward/upper range boundaries
At equatorial/lower range boundaries
81 %
75 %
19 %
25 %
Community (abundance) changes:
Cold-adapted species
Warm-adapted species
74 %
91 %
26 %
9%
81 %
19 %
Type of Analysis
Phenological
N = 484 / (678)
N = 460 / (920)
Meta-analysis
Range-boundaries (n=99)
Phenologies (n=172)
6.1 km-m/decade
< .1 x10-12
.013
northward/upward shift
2.3 d/decade advancement
< 0.05
Diverse species of: trees, herbs, shrubs, reptiles, amphibians, fish, marine zooplankton,
marine invertebrates, mammals, birds butterflies
30
(Parmesan & Yohe, Nature 2003)
Thought Exercise revisited
p = Probability of competing explanations (confounding factors)
π = Probability that observed change is really due to climate (mechanistic link)
n’/n = Proportion of species going in opposite direction to climate change predictions
Binomial probability model with each factor varying from 0 to 1
Here, p=0
1
Confidence Regions
0. 75
Very high
High
!
0. 5
Medium
Low
Minimum
Probability
(!)
!estimated confidence
0. 25
fromliterature review
0
0
0. 2
0. 4
(n'/n) Proportion
0. 6
0. 8
31
Very Long Biological Time Series Provide a Second
Type of ‘Fingerprint’
Global
Average
Temperature
32
Diagnostic Biological Fingerprint
“Sign--switching”
• Temporal
Advancement of timing or northward expansion in warm decades
('30s/40s & '80s/'90s); delay of timing or southward contraction in cool
decades ('50s/'60s)
• Spatial
Exhibited different behaviors at extremes of range boundary during
particular climate phase, e.g. expansion at northern range boundary
simultaneous with contraction at southern range boundary during
warming period
• Community
Abundance changes have gone in opposite directions for cold-adapted
vs. warm-adapted species. E.g. lowland birds increasing and montane
birds decreasing at mid-elevation site.
33
Shifts in Nationality: Novel Species
Sooty copper
(Heodes tityrus)
Photo removed
Heode s
t it yr us
20 ° E
60°
Fi nl a nd
Es t o ni a
N
Sw e de n
56°
Fra n c e
42°
Spa i n
40°
Ca t al o nia
Invasion of Estonia 100 km north
1998 - 1st record
1999 - breeding populations
2002 - increase #populations
& northward expansion
2005 - reached Baltic Sea
4° E
Contraction northward 50 km in Spain
1930s: common in Montseny mts, Catalonia
1980s - present: Extinct in Catalonia, southern-most
populations in the Pyrenees mts
Parmesan et al. 1999
34
Marine systems show declines of northern species
and increases of southern species
Shifts in fish community
Holbrook et al. 1997
35
Diagnostic Biological Fingerprint
• “Sign-Switching” uniquely predicted by climate change scenarios
found for 279 species
sign-switching pattern
Community
Abundance changes have gone in opposite directions for
cold-adapted vs. warm-adapted species. Usually local, but
many species in each category. Diverse taxa, n=2821
Temporal
Advancement of timing or northward expansion in warm
decades ('30s/40s & '80s/'90s); delay of timing or southward
contraction in cool decades ('50s/'60s)
30-132 yrs per species. Diverse taxa, n=441
Spatial
Exhibited different responses at extremes of range boundary
during particular climate phase. Data from substantial parts
of both northern and southern range boundaries for each
species. All species are northern hemisphere butterflies,
n=8
% of species showing
diagnostic pattern
80%
100%
100%
36
Diagnostic Biological Fingerprint
• “Sign-Switching” found for 294 species
– 100% follow decadal trends in temperatures
(range shifts and phenologies)
– 100% show geographic contractions coupled
with expansions at opposite edges of species range
– 80% of abundance shifts in communities
(local population dynamics noisy)
(Parmesan & Yohe 2003)
37
Studies of Observed Impacts on Natural
Biological Systems are Increasing
• 2001: IPCC TAR - 8 USA studies; ~20 global
• 2004 : Parmesan and Galbraith, Pew Report
• 40 USA studies (same criteria as synthesis
analysis in IPCC 2001)
• 21 studies “strong evidence”, >237 species
(stricter criteria than IPCC 2001)
• 2003 : Parmesan & Yohe, Nature
• 32 global studies (multispecies)
• > 1530 species/groups
38
Number of publications documenting a
response of a species, community or system to
recent climate change
(up to Jan. 2006)
#publications =
866
#species =
several
thousand
Parmesan AREES 2006
39
State of Science
Impacts
high
Established but
incomplete
Level of
Well - established
Climate
Change
Attribution
agreement:
Consensus
Speculative
Competing
explanations
low
low
high
Amount of evidence
(observations, theory, model outputs, etc.)
40 2004
Parmesan & Yohe, Nature 2003; Parmesan & Galbraith, Pew
Brief review of some specific impacts
41
Arctic Sea Ice down by 40% this year
(Area = ~half of lower USA lost) ~2-3° C
Magenta line = mean 1979-2000 = 6.74 mil Sq miles
NOAA, National Snow & Ice Data Center
Ringed Seal
• Declines in abundance, Hudson
Bay
Polar bear
• Need 2 kg fat / day
• Land animals & berries too lean
• Increase in ice-free season
• Increased summer starvation
period
• Declines in abundance &
weight, Hudson Bay
• Declines weight & #cubs,
Alaska & Norway
Stirling et al 1999; Derocher et al
2004; Derocher 2005; Ferguson et
al 2005
Polar bear
• Declines in abundance
& weight, Hudson Bay
• Declines weight &
#cubs, Alaska &
Norway
Ringed Seal
• Declines in
abundance, Hudson
Bay
NOAA, National Snow & Ice Data Center
Stirling et al 1999; Derocher et al
2004; Derocher 2005; Ferguson et
al 2005
44
Changes in Sea Ice
Driving Species
Range Shifts
Ice-dependent
species declining
by 70 - 95%
• Ice-adapted Adelie & Emperor
– moving poleward
• Warm-adapted Chinstrap & Gentoo
– Arrived 20-50 years ago
Smith et al. Bioscience 1999; Fraser et al. Polar Biol. 1992; Emslie
et al. Ant. Science 1998
Ice-dependent
species increasing or
smaller declines (<20%)
45
Pikas are Sensitive to Heat
•live > 7,500 feet
•Must forage
> 9 x / day
Smith 1974 46
Mountaintop Species : mac
• Sensitive to Heat
• Losing habitat as they are forced to
contract upward
American pika
• Live only > 7,500 feet
• Eat constantly
• Adults killed by > 31° C
(~ 90° F)
• Hide on hot days - starvation
Smith 1974
Low Elevation
Populations
Don’t Forage
Mid day
9,000 ft
August
9,000 ft
•Adults killed by
heat stress
( > 31° C in sun)
•Foraging time
limited by
temperature
May
12,500 ft
August
Smith 1974
48
Upward shift of
the pika
• 7 / 25 populations
have gone extinct
since 1930s
• Extinct
populations were
at lowest
elevations
Beever et al. 2003
Ice Age
Still present
extinct
49
Tropical
highland
frogs are
going extinct
• Cloud forest species require mist
• Population crashes followed years with high
#dry days, > 5 mist free days in a row
Pounds et al. Nature501999,
2006
Extinctions of harlequin frog species
(Atelopus) in central america cloud forest
Pounds et al 2006
Figure 1 | Altitudinal
patterns in the
Atelopus extinctions.
Bars indicate the
number of species
known per altitudinal
zone (total n •96), and
the grey-shaded
portions represent the
estimated percentage
of species lost from
each. This percentage
differs among zones
51
#species seen for last time
(black line) related to air
temp (blue line)
78% of species seen for last
time were preceded by an
extremely warm year
Pounds et al Nature 2006
52
a)
Elevation and min & max temp along mt
gradient in Costa Rica. Blk dashed is
thermal optimum, red is thermal range,
for Batrachochytrium (chytrid) fungus
b) #species of harlequin frog at each elev
(max upper boundary)
Pounds et al Nature 2006
Change in min
& max temps
at Monteverde
53
Andean Glacial Retreat: 3 species of frogs + fungus
migrated 400 m upward over 70 years
(0.3 ° C /decade)
1931
5000 m
2005
5400 m
Pleurodema
marmorata
Bufo
spinulosus
Telmatobius
marmoratus
**Chytrid fungus
Seimon et al. GCB 2007
Shrubs expanding into tundra in Alaska, Canada
Sturm et al.2001, unpubl
Shift in Alaskan tundra
carbon balance:
From sink
1980s
to source
1990s/2000
Losing 40 gC/m2/year
First signs of
positive feedbacks
Oechel et al., Nature 2000
55 2004
Parmesan & Galbraith
The toucan and other lowland tropical birds have moved uphill, threatening high elevation
birds.
Hydrology
and glaciers
Sea-Ice
Animals
Plants
Studies covering Studies using
large areas
remote sensing
56
Tropical species have moved into USA from
Central America, into Europe from Africa
Florida: 4 new species of dragonflies
(1960-2000)
Paulson 2001
Rufous hummingbird
• Migrant 1900-1990
•Resident by 1996
Texas:
5 new species of butterfly
• Colonized 400 km inland by 1998
Hill et al. 1998, Howell 2002
????
Mexican jay now resident
57
Community Replacement
Marine copepod plankton - community indicators in NE Atlantic
–
up to 1000 km northward shifts over 40 year
Beaugrand et al. Science 2002
58
Whole Ecosystems can collapse with single
extreme temperature event
Coral Reefs
and extreme
Sea Surface
Temperatures
(SST)
59
60
In 1998, coral bleaching affected every part
of the world’s oceans
•95% of coral bleached in Maldives, Western Australia,
Okinawa and Palau
•16 % of reefs killed
Aug 18
Feb
61
Hoegh-guldberg 1999
62
Hoegh-guldberg 1999
63
Ocean
acidifica
tion
Hoegh-guldberg et al Science 2007
64
Why is Climate Change a Conservation
Problem?
• Individual species have different responses and lag
times - led to disruption of communities and novel
(non-analog) communities during past major
climate changes
• Climate change adds yet another threat - wild life
may be able to cope with 1 threat, but not 3
simultaneously
• Modern ecosystems have lowered resiliency than
they did during past major (natural) climate
changes
65
Why is Resiliency Lower?
• Invasive species generally thrive in stressed conditions
• Coastal industry and urbanization limit the potential for
rising sea levels to simply move intertidal habitats (e.g.,
saltmarshes) inland.
• Natural ecosystems increasingly are confined to smaller and
more isolated fragments with reduced population sizes,
leading to:
• Diminished genetic variation - could limit local adaptation.
• Difficulty in simple shifts of species’ distributions.
• Decreased successful dispersal
• Lowered probability of successful colonization (farther
to travel & coming from smaller source populations
within impoverished communities).
66
So Species’ Shift
around with
Climate Change Why is this a
Problem?
52° N
48° N
44° N
40° N
Patterns of Edith’s
Checkerspot Population
Extinctions in natural
areas (good habitat)
36° N
% extinctions
> 70 %
32° N
35 - 55 %
< 20 %
67
Loss of Habitat
Add Climate Change
Endangered Sub-species
of Euphydryas editha
Endangered Sub-species
of Euphydryas editha
E. editha taylori
E. editha taylori
E. editha bayensis
E. editha bayensis
E. editha quino
E. editha quino
68
•
•
•
No evidence for macroevolution (emergence of novel adaptive traits within species)
Microevolution may facilitate species’ persistence
– Selection for high dispersal phenotypes improves changes of range shifts keeping
pace with climate change
– Species with variation of climate-adapted genotypes contain genetic flexibility to
cope in situ
High end of climate change projections problematic:
– Some habitats completely lost (tundra, alpine, coral reefs?)
– outside of evolutionary history of many species
– Unlikely for existing genetic variation to be sufficient
69
70
Evolution in populations of D.
subobscura
•Large #s of inversions
• Frequencies of inv change with
altitude and latitudinal clines
•Freq of inv change seasonally
•Both maintained dynamically by
selection because movement high
Balanya et al 2006: Change in
direction of the chromosome index
over time parallel those in the
temperature index at 22 of 26 sites
(upper rt and lower lft quadrants).
Black european; red N American; blue
71
S American. 1st pc explains 45%
Micro-evolutionary Responses
• Changes in gene frequencies within populations are
occurring
• Expect first evidence of evolutionary adaptation to
climate change in species with short generation times
• Many insects have generation time of 1-2 weeks
72
Long-term increases in frequencies of warmadapted genotypes
•D. melanogaster (4 deg. latitude shift in alcohol
dehydrogenase genes)
• D. subobscura (Europe, N & S America)
•D. robusta (USA)
• Pitcher plant mosquito (Wyeomyia smithii) (shift in
photoperiod cue for diapause, USA)
(Rodriguez-trelles & Rodriguez 1998; Balanya et al. 2003, Gilcrest; Levitan et al. 2003,
Bradshaw & Holzapfel 2001; Hoffmann et al. 2003)
Selection for high dispersal genotypes at expanding range
boundaries:
• Increase in frequencies of long-winged morphs along
northern colonizing wave in 2 sp. of bush cricket
(Thomas et al 2001)
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BUT - No Evidence for Macro-evolution
(i.e. across whole species)
• No response to artificial selection to tolerate more extreme
conditions than found in wild
• D. birchii (desiccation tolerance, Australia)
(Hoffmann et al. 2003)
• No evidence for new “super hot” mutations
• Paleological studies show similar stability of morphology over
short climate fluctuations (1000s of years)
• Fossil evidence indicates major climate regime shifts
associated with high extinction rates
• Evolution of novel forms takes 2 - 3 million years
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