Lecture 7 (Evolutionary ecology) - bio.classes.ucsc.edubio.classes.ucsc.edu/bioe107/Lecture 7...
Transcript of Lecture 7 (Evolutionary ecology) - bio.classes.ucsc.edubio.classes.ucsc.edu/bioe107/Lecture 7...
Evolutionary ecology
Interaction webInteractions include:•Consumer-prey•Competition•Mutualisms•Physical environment
Kinds of interactions
A. With physical environmentB. Species interactions
1) Directi. One-way interactionsii. Reciprocal interactions—can lead to coevolution
2) Indirect
Reciprocal interaction
A
B
Reciprocal interaction
A
B
Coevolution
Direct vs. indirect interactions
A B
C D
E F
Evolutionary Ecology—mostly considers:
1. how interactions (among species and between species and their physical environment) shape species through selection and adaptation;
2. consequences of the resulting evolutionary processes on populations, communities and ecosystems.
Example 1Endothermy in fishes
Influence of environment on speciescharacteristics
(Water Temperature)
Frequency (Hz)Frequency (Hz)00 22 44 66 88 1010 1212 1414
pow
er
W
pow
er
W
kgkg
11
00
22
44
66
88
1010
1212
1414
1515ooCC
2020ooCC2525ooCC
3030ooCC
T. T. albacaresalbacares
Hot Tuna are Faster & More PowerfulHot Tuna are Faster & More Powerful
Tunas Have High Oxidative Cell Tunas Have High Oxidative Cell MetabolismMetabolism
1
2
Scombroid fishes—tunas and billfishes
Tropical predatory fishes
• Billfish, tunas, sharks• Clear, warm water• Premium on performance of brain, vision• Evolution of endothermy• Rapid growth; short life spans
Example 2
Color and speciation in African cichlids
Species interactions
Loss of species
• Agriculture—nutrients and run-off• Reduced water clarity• Reduced color discrimination in cichlids• Loss of bright colors, increased
interbreeding, reduction in species
Coevolution
+/- antagonistic
-/- competive
+/+ mutualistic
+/o commensalistic
Consumer(Parasite)
Prey(Host)
DefenseResistance
+
-
Examples 3 and 4—coevolution in antagonists
Example 3—nest parasites, coevolution in hosts and parasites
Robin
Pied wagtail
Dunnock
Reed warbler
Meadow pipit
Great reed warbler
Example 4—food chain length and plant/herbivore coevolution
Plants
Herbivores
Even-number Odd-numbered
Stronginteraction
Weakinteraction
The players
Sea otters Sea urchins Macroalgae
In situ grazing
-20
0
20
40
60
80
100
Otters Abundant Otters Absent
Perc
ent L
oss
per 2
4 hr
Experimental
Control
Approach: North Pacific/Australasian comparison
Kelp Forest of the World
Mann 1972
Plant/herbivore coevolution
Plants
Herbivores
Carnivores
Australasia Northeast Pacific
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
0
0.05
0.10.15
0.2
0.25
0.3
0.350.4
0.45
0.5
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Northeast Pacific OceanN = 27 Species
AustralasiaN = 39 Species
% Total Phlorotannins
Prop
ortio
n of
Spe
cies
% Dry Wt.
513.4
513.4
513.4
513.4
Phlorotannins from
New Zealand Algae
Ecklonia radiata
Carpophyllum maschalocarpum
North American Algae
Agarum cribrosum
Dictyoneurum californicum
Tegulafunebralis
Tegulabrunnea
* NS
* ***
S.purpuratus
California Herbivores
* * *
* NS NS
NS
0.073 ** *
** ** *
NS ** *
** *
Evechinus chloroticus
NS
NSNS*
0.057
TurboCentrostephanusrodgersii sulcata
New Zealand Herbivores
NS NS* NS
******
smaragdusCook ia
NSNS NS
NS NSNSNSNS
NSNSNSNS
NSNS
NS*
NS*
ndndNS
*
Steinberg, Estes & Winter, PNAS, 1995
Plants
Herbivores
Carnivores
Defense
Resistance
Example 5
Indirect effects:
Sea otters on kelp (previous)
Led to• Steller’s sea cow• Body size in abalones
Steller sea cow
•A dugongid sirenian—radiated into North Pacific with onsetof recent Glacial Age and polar cooling in the North Pacific.
•An obligate kelp feeder—dentition used for feeding on marine angiosperms lost entirely.
•Patterns driven by the radiation and proliferation of the kelps.
Steller’s sea cow
Sea otter Limit grazing urchinsPoorly defended (high quality) kelp
Radiation of hydrodamalineSirenians (Steller sea cows)In the North Pacific
Abalones--why interesting?
Good fossil record
Variation in maximum size among species
H. varia
H. rufescens
22
1
5
2
4
4
3
1
7
22
110 8
7
7
101
79
8
= Cretaceous = Paleogene= Neogene= Pleistocene
Numerals represent extant species
Fossil and extant abalones
Maximum size vs. habitat
Japan
NE Pacific
Australia
New Zealand
East Africa
Indo-Pacific
W Atlantic-Caribbean
Tropical E Pacific
South African
Mediterranean
W Africa
Sea otter Limit grazing urchinsPoorly defended (high quality) kelp
Evolution of large body size in abalones
Spatio-temporal patterns in co-evolution
A Greya Moth about to Lay Eggs In, and Pollinate, a Woodland Star (Lithophragma) Flower
Pollen at end ofmoth’s abdomen
Source: John N Thompson
Flower-moth interactionsMoth:• Deposits eggs in floral ovary• Pollinate flower but moth larvae feed on developing
seeds
Plant:• Benefits from pollination (mutualism) but incurs cost from
seed loss (antagonism)
By comparing plant reproductive success between floral capsules with and without moth eggs, it is possible to determine if the interaction is commensal, antagonistic, or mutualistic
WithGreya eggs
Assessing Whether Woodland Star Plants Depend on Greya moths
Without Greya eggs
Source: John N Thompson
California
Oregon
Washington
Idaho
IDAHO0 100Km.
Salmon R.
Selway R.
Snake R.
= Mutualistic= Antagonistic= Commensalistic
Thompson and Cunningham 2002 NatureThompson and Fernandez 2006 Ecology
Geographic Mosaic of Ecological Outcomes
• Geographic selection mosaics (GxGxE)• Coevolutionary hotspots and coldspots• Trait remixing
Source: John N Thompson
Geographic Mosaic of Coevolution:Coevolution as an Ongoing Ecological Process
Trophy Hunting
Fisheries
Often target the larger fish in a population
Silversides
David Conover, SUNY Stony Brook
Smaller individuals selectively removed
Larger individuals selectively removed
Monhegan 1880s
Cod in the Gulf of Maine
0500100015002000250030003500400045000
20
40
60
80
100
120
Years Before Present
Atla
ntic
cod
bod
y le
ngth
(cm
)Cod Size Over Past 4500 years
5000
New synthesis of evolutionary ecology
ECO
EVO
ECO EVO
Fig. 1 (A) Dynamics for evolutionary and ecological traits in G. fortis.
T W Schoener Science 2011;331:426-429
Published by AAAS
Fig. 2 (A) Population numbers for the five ungulate species in Ezard et al.’s (18) study.
T W Schoener Science 2011;331:426-429
Published by AAAS
Fig. 4 Experimental approach used in ongoing study of eco-evolutionary dynamics in Caribbean lizards.
T W Schoener Science 2011;331:426-429
Published by AAAS