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Species interac,on networks, global change and restora,on Daniel Montoya ([email protected]) Bilbao, April 2015

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Page 1: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Species  interac,on  networks,  global  change  and  restora,on  

Daniel  Montoya  ([email protected])  

Bilbao,  April  2015  

Page 2: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)
Page 3: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

STRUCTURE  

STABILITY   FUNCTION  

Page 4: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

STRUCTURE  

STABILITY   FUNCTION  

TIME  

Page 5: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 6: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 7: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Complexity-­‐Stability.  Background  

•  1950s-­‐1960s:  More  complex,  more  stable      Elton,  Hutchinson  

•  1970s:  More  complex,  less  stable      Robert  May  

•  1980s-­‐2010s:  More  complex,  more  stable?      Pimm,  Lawton,  Bascompte,  Olesen,  and  many  more…  

•  Today’s  challenge:  Mul,ple  stability  +  Quan,ta,ve  interac,ons  

 

Page 8: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model.  Space  &  Mul,ple  interac,ons  

Lurgi,  M.  et  al  (Theore,cal  Ecology,  In  press)    

///  Mutualism  :  Antagonism  ra,os  

Spa,ally-­‐explicit  model  

Individual-­‐based  

Page 9: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model.  Space  &  Mul,ple  interac,ons  

Lurgi,  M.  et  al  (Theore,cal  Ecology,  In  press)    

species are becoming weaker (those with less abundant prey).This could in turn cause a shift in the distribution of thestrengths of interactions towards lower values, a distinctivefeature of more stable communities (McCann 2000; Neutelet al. 2002). Interestingly, the distribution of interactionstrengths at the community level was largely affected byMAI ratios, withweaker interactions becomingmore commonin communities with higher MAI ratios. Therefore, a higherfraction of mutualistic species promotes community stabilityby shifting the distribution of interaction strengths towardslower values.

The likely mechanism behind the observed changes in in-teraction strength patterning is a differential spatial aggrega-tion of species per trophic level. Both global (Moran’s I) andlocal (Geary’s C) aggregation metrics were positively influ-enced byMAI ratios at the whole community level, with sometrophic groups displaying a stronger relationship than others.The populations of basal species (plants) were more aggregat-ed at higher MAI ratios. This higher spatial aggregation ofprimary producers is likely due to the fact that mutualisticconsumers take up fewer resources from their interaction part-ners. Populations of mutualistic plants can thus remain more

aggregated due to decreased mortality and hence increasedlocal reproduction. Additionally, given that there are less her-bivore species as MAI ratio increases, non-mutualistic plantsremain more clustered. Regardless of the mechanisms behindthe aggregation of basal species (e.g. decreased mortality, in-creased local reproduction, herbivory release), the effects ofthis aggregation percolates up through the food chains, possi-bly by inducing herbivores (and mutualistic animals) to re-main near aggregated food sources, and hence predator spe-cies become more clustered as MAI ratio increases. In sum-mary, spatial aggregation offers a potential explanation to whyinteractions in the community are becoming weaker in gener-al, as suggested by the decrease in Gq. Consumers will bemore likely to interact with the same prey species if they areaggregated around them, in detriment of their other potentialinteractions as defined in the niche model.

Our results seem to contradict those of Mougi and Kondoh2012, who found that higher levels of mutualisms have adestabilising effect on the communities with a mixture of an-tagonistic and mutualistic interactions. Even though space hasan important influence on the stability of ecological commu-nities (whether natural or artificial), we should not overlook

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Fig. 7 Moran’s I spatialaggregation index per trophiclevel as a function of MAI ratio.Points show index values for eachreplicate. Line and shadow oneach plot represent the fit of alinear model to the data and thestandard error of the mean,respectively. ** and ***correspond to p values <0.01 and0.001 for linear models fit to eachdata set, respectively

Theor Ecol

More  spa,al  aggrega,on  with  increasing  mutualism  

Page 10: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model.  Space  &  Mul,ple  interac,ons  

Lurgi,  M.  et  al  (Theore,cal  Ecology,  In  press)    

with MAI ratio (Fig. 6, p<0.001 for all pairwise comparisonsbetween distributions). This result suggests that mutualisticinteractions make communities more stable by lowering theaverage strength of ecological relationships between species.

MAI ratios did not affect temporal stability (i.e. populationvariability through time), spatial stability (as measured by thechange in the centroid of the species’ spatial range) or the areaand density of species populations. In contrast, higher MAIratios resulted in significantly higher and lower Moran’s I andGeary’s C indexes, respectively (correlation tests using linearmodels yielded F(1273)=29.06, p<0.01 for Moran’s I andF(1273)=24.35, p<0.01 for Geary’s C against MAI ratios),revealing more spatially aggregated populations with increas-ingMAI ratios (Fig. S3). Increases in spatial aggregation weredifferent across trophic levels both at global (Moran’s I) andlocal (Geary’s C) scales. For example, whereas predators andplants got significantly more aggregated as MAI ratio in-creased, the aggregation of mutualistic animals and herbivoreswas either not affected or only weakly affected by changingMAI ratios, respectively (Fig. 7 and S4). We argue that morespatially aggregated populations can be associated with higherreproductive potential stability, as the likelihood of finding areproductive partner in the neighbourhood is higher. From thisperspective, communities in general, and plant and predatorspecies in particular, were thus more stable in terms of speciesreproductive potential as the MAI ratio increased (Fig. 7, S3and S4).

Discussion

The consideration of different interaction types simultaneous-ly within the same ecological network has consistent and pre-dictable effects on community organisation and stabilityacross a gradient of antagonistic vs. mutualistic interactions.We have shown that increasing levels of mutualisms result in

more stable communities. More importantly, increasing theproportion of mutualistic vs. antagonistic interactions (i.e.MAI ratios) influences different dimensions of ecological sta-bility in different ways, although never negatively. Stabilitywas either not influenced by increasing mutualism—in thecases of population stability and species’ spatial distribu-tions—or was positively influenced by them—spatial aggre-gation, distribution of interaction strengths. The question aris-ing is: why were some components of stability affected byMAI ratios and others were not?

Stability of our model communities in terms of the variabil-ity in the population dynamics of their constituent species wasnot affected by the MAI ratio. This could be a consequence ofthe stabilising effect of space on complex communities, as hasbeen previously demonstrated (e.g. (Solé and Bascompte2006)), regardless of the type of interaction considered.Several mechanisms that could yield these stability patternsdue to spatial arrangements within communities, such asmetapopulation dynamics and refugee effects, are in place inour model. Metapopulation dynamics, via the exchange ofindividuals among local populations, could be an importantfactor determining the fate of species, preventing them fromgoing extinct (Hanski 1998). Metapopulation structure in ourmodel communities emerges as a property of the system fromorganisation of individuals at the local scale. Also, the refugeeeffect created by highly aggregated populations (see Fig. 7),which prevents predators from attacking individuals at thecore of these populations, could drive stability at the popula-tion level. Collectively, these factors could have profound im-pacts on the ability of predators to capture prey as mutualismsincrease. It is possible however that the opposite pattern couldarise, whereas a more aggregated prey distribution would al-low predator individuals to find the ‘next’ prey to attack morereadily. This would result in higher attack rates. The emer-gence of this pattern would make communities displaying itless able to persist through time since the predator would forcetheir prey into an extinction vortex. This suggests that a goodbalance between prey aggregation and attack rate must befound to enhance persistence. The key to this balance couldlie on the strength of ecological interactions.

Our results showed that increasing MAI ratios results inmodel communities with a lower quantitative generality(Gq). Because quantitative generality measures the generalityof consumers, this indicates that predators, even when keepingall of their prey species as MAI increases, are becoming morespecialised (i.e. they are more likely to interact with some oftheir prey species than with others). Since our model does notenforce any kind of prey preference or selection, this is exclu-sively a consequence of an increased abundance of those ‘pre-ferred’ prey species. A higher proportion of mutualistic inter-actions promotes the dominance of certain prey species thatare becoming relatively more abundant. As a result and inparallel to this pattern, some of the interactions of generalist

0

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0 .0025 .005 .0075 .01Interaction strength

Fre

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0.1.2.3.4.5.6.7.8.9 1

Fig. 6 Frequency distributions of interaction strengths in the overallecological network across different values of MAI ratio

Theor Ecol

Page 11: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model.  Space  &  Mul,ple  interac,ons  

Lurgi,  M.  et  al  (Theore,cal  Ecology,  In  press)    

•  Importance  of  considering  mul,ple  interac,on  types,    and  stability  metrics  

•  Complex  feedbacks:  topology,  space,  individual  behavior?  

with MAI ratio (Fig. 6, p<0.001 for all pairwise comparisonsbetween distributions). This result suggests that mutualisticinteractions make communities more stable by lowering theaverage strength of ecological relationships between species.

MAI ratios did not affect temporal stability (i.e. populationvariability through time), spatial stability (as measured by thechange in the centroid of the species’ spatial range) or the areaand density of species populations. In contrast, higher MAIratios resulted in significantly higher and lower Moran’s I andGeary’s C indexes, respectively (correlation tests using linearmodels yielded F(1273)=29.06, p<0.01 for Moran’s I andF(1273)=24.35, p<0.01 for Geary’s C against MAI ratios),revealing more spatially aggregated populations with increas-ingMAI ratios (Fig. S3). Increases in spatial aggregation weredifferent across trophic levels both at global (Moran’s I) andlocal (Geary’s C) scales. For example, whereas predators andplants got significantly more aggregated as MAI ratio in-creased, the aggregation of mutualistic animals and herbivoreswas either not affected or only weakly affected by changingMAI ratios, respectively (Fig. 7 and S4). We argue that morespatially aggregated populations can be associated with higherreproductive potential stability, as the likelihood of finding areproductive partner in the neighbourhood is higher. From thisperspective, communities in general, and plant and predatorspecies in particular, were thus more stable in terms of speciesreproductive potential as the MAI ratio increased (Fig. 7, S3and S4).

Discussion

The consideration of different interaction types simultaneous-ly within the same ecological network has consistent and pre-dictable effects on community organisation and stabilityacross a gradient of antagonistic vs. mutualistic interactions.We have shown that increasing levels of mutualisms result in

more stable communities. More importantly, increasing theproportion of mutualistic vs. antagonistic interactions (i.e.MAI ratios) influences different dimensions of ecological sta-bility in different ways, although never negatively. Stabilitywas either not influenced by increasing mutualism—in thecases of population stability and species’ spatial distribu-tions—or was positively influenced by them—spatial aggre-gation, distribution of interaction strengths. The question aris-ing is: why were some components of stability affected byMAI ratios and others were not?

Stability of our model communities in terms of the variabil-ity in the population dynamics of their constituent species wasnot affected by the MAI ratio. This could be a consequence ofthe stabilising effect of space on complex communities, as hasbeen previously demonstrated (e.g. (Solé and Bascompte2006)), regardless of the type of interaction considered.Several mechanisms that could yield these stability patternsdue to spatial arrangements within communities, such asmetapopulation dynamics and refugee effects, are in place inour model. Metapopulation dynamics, via the exchange ofindividuals among local populations, could be an importantfactor determining the fate of species, preventing them fromgoing extinct (Hanski 1998). Metapopulation structure in ourmodel communities emerges as a property of the system fromorganisation of individuals at the local scale. Also, the refugeeeffect created by highly aggregated populations (see Fig. 7),which prevents predators from attacking individuals at thecore of these populations, could drive stability at the popula-tion level. Collectively, these factors could have profound im-pacts on the ability of predators to capture prey as mutualismsincrease. It is possible however that the opposite pattern couldarise, whereas a more aggregated prey distribution would al-low predator individuals to find the ‘next’ prey to attack morereadily. This would result in higher attack rates. The emer-gence of this pattern would make communities displaying itless able to persist through time since the predator would forcetheir prey into an extinction vortex. This suggests that a goodbalance between prey aggregation and attack rate must befound to enhance persistence. The key to this balance couldlie on the strength of ecological interactions.

Our results showed that increasing MAI ratios results inmodel communities with a lower quantitative generality(Gq). Because quantitative generality measures the generalityof consumers, this indicates that predators, even when keepingall of their prey species as MAI increases, are becoming morespecialised (i.e. they are more likely to interact with some oftheir prey species than with others). Since our model does notenforce any kind of prey preference or selection, this is exclu-sively a consequence of an increased abundance of those ‘pre-ferred’ prey species. A higher proportion of mutualistic inter-actions promotes the dominance of certain prey species thatare becoming relatively more abundant. As a result and inparallel to this pattern, some of the interactions of generalist

0

100

200

300

400

0 .0025 .005 .0075 .01Interaction strength

Fre

quen

cy

MAI ratio

0.1.2.3.4.5.6.7.8.9 1

Fig. 6 Frequency distributions of interaction strengths in the overallecological network across different values of MAI ratio

Theor Ecol

Page 12: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 13: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Biodiversity-­‐Ecosystem  Func,oning      -­‐  Few  species  (mostly  grassland  

 plants)  -­‐  No  trophic  levels  -­‐  Controlled  experiments  -­‐  From  single  to  mulIple  funcIons  -­‐  From  species  to  funcIonal  groups  

Background  

Food  web  research      -­‐  MulIple  species,  trophic  levels,  

indirect  effects  -­‐  Structure-­‐Stability  -­‐  Surrogate  measures  of  funcIon  

Cedar  Creek  experiment   Rooney  &  McCann  (TREE  2012)  Norwood  food  web  (Pocock  et  al.  Science  2012)  

Page 14: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

2.  Is  there  any  relaIonship  between  food  web  structure  and  ecosystem  funcIoning?  

1.  How  funcIonal  diversity  is  distributed  in  space?  

Page 15: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

PORTISHEAD  

SAND  BAY  

STEART  

POET'S  CORNER,  CLEVEDON    

Bristol  Channel  

10  Km  

Page 16: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Salt  marsh  ecosystems  

Page 17: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

PORTISHEAD  

SAND  BAY  POET'S  CORNER,  CLEVEDON    

STEART  

                             115  islands  (27-­‐31  per  archipelago)    Size:  0.2  –  52.4  m2  

                 Distance  to  mainland:  1.3  –  250  m  

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Diatoms  

Crabs  

Gastropods  Collembola  

Crane  flies  

Pollinator  insects  

Amphipods  

Money  spiders  

Carabid  beetles  

Green  algae  

Brown  algae  

Terrestrial  plants  

ISLAND  SALT  MARSH  FOOD-­‐WEB  

Page 23: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

EXAMPLE  ARCHIPELAGO  (POET'S  CORNER,  CLEVEDON)    

Page 24: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

EXAMPLE  ARCHIPELAGO  (POET'S  CORNER,  CLEVEDON)    

Page 25: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

EXAMPLE  ARCHIPELAGO  (POET'S  CORNER,  CLEVEDON)    

x    4  

Page 26: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

115  islands  ‘networks  of  networks’  

Montoya  et  al.  (Nat.  Commun.  2nd  review)  

Page 27: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

1.  How  funcIonal  diversity  is  distributed  in  space?  

Montoya  et  al.  (Nat.  Commun.  2nd  review)  

Page 28: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

1.  How  funcIonal  diversity  is  distributed  in  space?  

Some  islands  are  funcIonally  more  ‘important’  than  others  

Montoya  et  al.  (Nat.  Commun.  2nd  review)  

Page 29: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

SpaIal  Generalized  EsImaIon  EquaIons:  Func%onal  Diversity  ~  Diversity  +  Network  Proper%es  +  Island  Size  +  Distance  

2.  RelaIonship  food  web  structure-­‐funcIonal  diversity?  

Montoya  et  al.  (Nat.  Commun.  2nd  review)  

Page 30: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

FuncIonal  groups    form  modules    

     

Modular  architectures  

increase  funcIonal  diversity  

SpaIal  Generalized  EsImaIon  EquaIons:  Func%onal  Diversity  ~  Diversity  +  Network  Proper%es  +  Island  Size  +  Distance  

2.  RelaIonship  food  web  structure-­‐funcIonal  diversity?  

Montoya  et  al.  (Nat.  Commun.  2nd  review)  

Page 31: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

2.  RelaIonship  food  web  structure-­‐funcIonal  diversity?  

Olesen  et  al.  (PNAS  2007),  Montoya  et  al.  (Nat.  Commun.  2nd  review)  

FuncIonal  groups    form  modules    

     

Modular  architectures  

increase  funcIonal  diversity  

Page 32: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

2.  Is  there  any  relaIonship  between  food  web  structure  and  ecosystem  funcIoning?  

1.  How  funcIonal  diversity  is  distributed  in  space?  

Heterogeneous  distribuIon  à  Some  islands  are  funcIonally  more  ‘important’  than  others    

FuncIonal  diversity  increases  with  modularity  à  Link  between  food  web  structure  and  funcIoning    

CONCLUSIONS  

Page 33: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

2.  Is  there  any  relaIonship  between  food  web  structure  and  ecosystem  funcIoning?  

1.  How  funcIonal  diversity  is  distributed  in  space?  

Heterogeneous  distribuIon  à  Some  islands  are  funcIonally  more  ‘important’  than  others    

FuncIonal  diversity  increases  with  modularity  à  Link  between  food  web  structure  and  funcIoning    

CONCLUSIONS  

 Structure  and  func,on  are  

related  in  food  webs    

Page 34: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 35: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Jouzel  et  al.  (Science  2013)  

Climate  Change  in  the  Quaternary  

Page 36: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Blois  et  al.  (Science  2013)  

Climate  Change  in  the  Quaternary  

Page 37: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

How  long-­‐term  community  dynamics  and  structure  at  regional  scales  have  changed  over  the  last  ≈  1  million  years?        Are  these  changes  associated  to  Quatenary  climate  changes?  

Page 38: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

 The  dataset  

-­‐  Last  850,000  years  (Pleistocene  +  Holocene  periods)  

-­‐  6  Ime  periods:  EP,  MP,  LIM,  LGM,  H,  C    -­‐  Number  of  glacial  cycles  between  periods  as  a  proxy  for  climate  changes  

(MIS/OIS  boundaries)    -­‐  Large  cummulaIve  food  webs  (71  fossil  sites  IB)  

-­‐  Large  body-­‐size  mammals  (>20Kg)  

-­‐  Trophic  links?  

Page 39: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

6  regional  large  mammal  communiIes  

ExIncIon,  immigraIon  &  turnover  rates      Random    Body  size  Phylogeny  

 Food  web  properIes:  SR,  L,  C,  Vul,  Gen,  P:P,  Robustness,  Nestedness  

Page 40: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

ExIncIons  not  related  with  body  size    ImmigraIons:  support  PCH    ExIncIon    ≤    ImmigraIon  à  éSpecies  richness  (1/20-­‐36ky)        (1/12-­‐36ky)  

ExIncIons:  affect  large-­‐bodied  and  specialist  species    ImmigraIon  rate  drops.  No  new  predators.    éExIncIon  >>  ImmigraIon  à  êSpecies  richness  (1/0.83ky)    

1.  How  long-­‐term  community  dynamics  and  structure  at  regional  scales  have  changed  over  the  last  ≈1  my?  

Pleistocene   Holocene   Pleistocene  

Holocene  

Page 41: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Pleistocene  

Holocene  

ExIncIons  not  related  with  body  size    ImmigraIons:  support  PCH    ExIncIon    ≤    ImmigraIon  à  éSpecies  richness  (1/20-­‐36ky)        (1/12-­‐36ky)    Network  properIes  relaIvely  constant    Stability  relaIvely  constant  

ExIncIons  affect  large-­‐bodied  and  specialist  species    ImmigraIon  rate  drops.  No  new  predators.    éExIncIon  >>  ImmigraIon  à  êSpecies  richness  (1/0.83ky)    éConnectance  êGen,  Vul,  Pred:Prey    Stability??  

1.  How  long-­‐term  community  dynamics  and  structure  at  regional  scales  have  changed  over  the  last  ≈1  my?  

Page 42: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

2.  Are  these  changes  associated  to  Quatenary  climate  changes?  

Changes  in  food  web  structure  between  Pleistocene  &  Holocene  mammal  communiIes  associated  with  the  loss  of  specialist  predators  and  increases  in  

connectance  following  a  non-­‐random  reducIon  in  community  size  

Page 43: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

•  Dynamic  and  structural  changes  in  the  Holocene  associated  to  anatomically  modern  humans:  H.  sapiens  as  a  central  node  in  the  network  

Conclusions  

•  Despite  species  turnover,  Pleistocene  communiIes  reorganized  with  the  arrival  of  phylogeneIcally  similar  species  without  major  changes  in  food  web  structure  and  stability  

•  Pleistocene  Vs  Holocene:  Holocene  communiIes  are  remnants  of  larger  Pleistocene  megafaunas  

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Conclusions  

Impacts  on  funcIoning?  

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Conclusions  

Impacts  on  funcIoning?  

Contemporary  climate  change?  

Page 46: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 47: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 48: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

EMBARGOED UNTIL 2PM U.S. EASTERN TIME ON THE THURSDAY BEFORE THIS DATE:

15. A. Woolfe et al., PLoS Biol. 3, e7 (2005).16. A. Siepel et al., Genome Res. 15, 1034 (2005).17. L. Z. Holland et al., Genome Res. 18, 1100 (2008).18. Materials and methods are available as supporting

material on Science Online.19. K. S. Pollard, M. J. Hubisz, K. R. Rosenbloom, A. Siepel,

Genome Res. 20, 110 (2010).20. International HapMap Consortium, Nature 449, 851

(2007).21. G. Robertson et al., Nat. Methods 4, 651 (2007).22. G. E. Crawford et al., Genome Res. 16, 123 (2006).23. A. P. Boyle et al., Cell 132, 311 (2008).

24. A. Valouev et al., Nat. Methods 5, 829 (2008).25. M. Ashburner et al., Nat. Genet. 25, 25 (2000).26. C. Y. McLean et al., Nat. Biotechnol. 28, 495

(2010).27. C. J. Bult, Nucleic Acids Res. 36, D724 (2008).28. P. Wu et al., Int. J. Dev. Biol. 48, 249 (2004).Acknowledgments: This work was supported by the Howard

Hughes Medical Institute (C.B.L., S.R.S., D.M.K., D.H.),the NSF (CAREER-0644282 to M.K., DBI-0644111 toA.S.), the NIH (R01-HG004037 to M.K., P50- HG02568to D.M.K., U54-HG003067 to K.L-T., 1U01-HG004695to C.B.L., 5P41-HG002371to B.J.R.), the Sloan

Foundation (M.K.), and the European Science Foundation(EURYI to K.L-T.).

Supporting Online Materialwww.sciencemag.org/cgi/content/full/333/6045/[page]/DC1Materials and MethodsFigs. S1 to S9Tables S1 to S12References (29–49)

10 January 2011; accepted 24 June 201110.1126/science.1202702

Rapid Range Shifts of SpeciesAssociated with High Levelsof Climate WarmingI-Ching Chen,1,2 Jane K. Hill,1 Ralf Ohlemüller,3 David B. Roy,4 Chris D. Thomas1*

The distributions of many terrestrial organisms are currently shifting in latitude or elevation in responseto changing climate. Using a meta-analysis, we estimated that the distributions of species haverecently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudesat a median rate of 16.9 kilometers per decade. These rates are approximately two and three timesfaster than previously reported. The distances moved by species are greatest in studies showing thehighest levels of warming, with average latitudinal shifts being generally sufficient to track temperaturechanges. However, individual species vary greatly in their rates of change, suggesting that therange shift of each species depends on multiple internal species traits and external drivers of change.Rapid average shifts derive from a wide diversity of responses by individual species.

Threats to global biodiversity from climatechange (1-8) make it important to identifythe rates at which species have already

responded to recent warming. There is strong evi-dence that species have changed the timing oftheir life cycles during the year and that this islinked to annual and longer-term variations intemperature (9–12). Many species have alsoshifted their geographic distributions towardhigher latitudes and elevations (13–17), but thisevidence has previously fallen short of demon-strating a direct link between temperature changeand range shifts; that is, greater range shifts havenot been demonstrated for regions with the high-est levels of warming.

We undertook a meta-analysis of availablestudies of latitudinal (Europe, North America,and Chile) and elevational (Europe, North Amer-ica, Malaysia, and Marion Island) range shifts fora range of taxonomic groups (18) (table S1). Weconsidered N = 23 taxonomic group ! geographicregion combinations for latitude, incorporating764 individual species responses, and N = 31

taxonomic group ! region combinations for ele-vation, representing 1367 species responses. Forthe purpose of analysis, the mean shift across allspecies of a given taxonomic group, in a givenregion, was taken to represent a single value (forexample, plants in Switzerland or birds in NewYork State; table S1) (18).

The latitudinal analysis revealed that spe-cies have moved away from the Equator at a

median rate of 16.9 km decade!1 (mean = 17.6km decade!1, SE = 2.9, N = 22 species group !region combinations, one-sample t test versuszero shift, t = 6.10, P < 0.0001). Weighting eachstudy by the "(number of species) in the group !region combination gave a mean rate of 16.6 kmdecade!1. For elevation, there was a median shiftto higher elevations of 11.0 m uphill decade!1

(mean = 12.2 m decade!1, SE = 1.8, N = 30 spe-cies groups ! regions, one-sample t test versuszero shift, t = 7.04, P < 0.0001). Weighting ele-vation studies by "(number of species) gave amean rate of uphill movement of 11.1 m decade!1.

A previous meta-analysis (14) of distribu-tion changes analyzed individual species, ratherthan the averages of taxonomic groups ! regionsthat we used, and also included data on latitu-dinal and elevational shifts in the same analysis(18). It concluded that ranges had shifted towardhigher latitudes at 6.1 km decade!1 and to high-er elevations at 6.1 m decade!1 (14), whereasthe rates of range shift that we found were sig-nificantly greater [N = 22 species groups ! regions,one-sample t test versus 6.1 km decade!1, t =3.99, P = 0.0007 for latitude; N = 30 groups !regions, one-sample t test versus 6.1 m decade!1,t = 3.49, P = 0.002 for elevation (18)]. Ourestimated mean rates are approximately threeand two times higher than those in (14), for

1Department of Biology, University of York, Wentworth Way,York YO10 5DD, UK. 2Biodiversity Research Center, AcademiaSinica, 128 Academia Road, Section 2, Nankang Taipei 115,Taiwan. 3School of Biological and Biomedical Sciences, andInstitute of Hazard, Risk and Resilience, Durham University,South Road, Durham DH1 3LE, UK. 4Centre for Ecology &Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire,OX10 8BB, UK.

*To whom correspondence should be addressed. E-mail:[email protected]

Fig. 1. Relationship between observed and expected range shifts in response to climate change, for (A)latitude and (B) elevation. Points represent the mean responses (TSE) of species in a particular tax-onomic group, in a given region. Positive values indicate shifts toward the pole and to higher ele-vations. Diagonals represent 1:1 lines, where expected and observed responses are equal. Open circles,birds; open triangles, mammals; solid circles, arthropods; solid inverted triangles, plants; solid square,herptiles; solid diamond, fish; solid triangle, mollusks.

19 AUGUST 2011 VOL 333 SCIENCE www.sciencemag.org1024

REPORTS

Chen  et  al.  (Science  2011)  

Climate  change.  Distribu,on  shihs  

European  Environment  Agency  

Page 49: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

EMBARGOED UNTIL 2PM U.S. EASTERN TIME ON THE THURSDAY BEFORE THIS DATE:

15. A. Woolfe et al., PLoS Biol. 3, e7 (2005).16. A. Siepel et al., Genome Res. 15, 1034 (2005).17. L. Z. Holland et al., Genome Res. 18, 1100 (2008).18. Materials and methods are available as supporting

material on Science Online.19. K. S. Pollard, M. J. Hubisz, K. R. Rosenbloom, A. Siepel,

Genome Res. 20, 110 (2010).20. International HapMap Consortium, Nature 449, 851

(2007).21. G. Robertson et al., Nat. Methods 4, 651 (2007).22. G. E. Crawford et al., Genome Res. 16, 123 (2006).23. A. P. Boyle et al., Cell 132, 311 (2008).

24. A. Valouev et al., Nat. Methods 5, 829 (2008).25. M. Ashburner et al., Nat. Genet. 25, 25 (2000).26. C. Y. McLean et al., Nat. Biotechnol. 28, 495

(2010).27. C. J. Bult, Nucleic Acids Res. 36, D724 (2008).28. P. Wu et al., Int. J. Dev. Biol. 48, 249 (2004).Acknowledgments: This work was supported by the Howard

Hughes Medical Institute (C.B.L., S.R.S., D.M.K., D.H.),the NSF (CAREER-0644282 to M.K., DBI-0644111 toA.S.), the NIH (R01-HG004037 to M.K., P50- HG02568to D.M.K., U54-HG003067 to K.L-T., 1U01-HG004695to C.B.L., 5P41-HG002371to B.J.R.), the Sloan

Foundation (M.K.), and the European Science Foundation(EURYI to K.L-T.).

Supporting Online Materialwww.sciencemag.org/cgi/content/full/333/6045/[page]/DC1Materials and MethodsFigs. S1 to S9Tables S1 to S12References (29–49)

10 January 2011; accepted 24 June 201110.1126/science.1202702

Rapid Range Shifts of SpeciesAssociated with High Levelsof Climate WarmingI-Ching Chen,1,2 Jane K. Hill,1 Ralf Ohlemüller,3 David B. Roy,4 Chris D. Thomas1*

The distributions of many terrestrial organisms are currently shifting in latitude or elevation in responseto changing climate. Using a meta-analysis, we estimated that the distributions of species haverecently shifted to higher elevations at a median rate of 11.0 meters per decade, and to higher latitudesat a median rate of 16.9 kilometers per decade. These rates are approximately two and three timesfaster than previously reported. The distances moved by species are greatest in studies showing thehighest levels of warming, with average latitudinal shifts being generally sufficient to track temperaturechanges. However, individual species vary greatly in their rates of change, suggesting that therange shift of each species depends on multiple internal species traits and external drivers of change.Rapid average shifts derive from a wide diversity of responses by individual species.

Threats to global biodiversity from climatechange (1-8) make it important to identifythe rates at which species have already

responded to recent warming. There is strong evi-dence that species have changed the timing oftheir life cycles during the year and that this islinked to annual and longer-term variations intemperature (9–12). Many species have alsoshifted their geographic distributions towardhigher latitudes and elevations (13–17), but thisevidence has previously fallen short of demon-strating a direct link between temperature changeand range shifts; that is, greater range shifts havenot been demonstrated for regions with the high-est levels of warming.

We undertook a meta-analysis of availablestudies of latitudinal (Europe, North America,and Chile) and elevational (Europe, North Amer-ica, Malaysia, and Marion Island) range shifts fora range of taxonomic groups (18) (table S1). Weconsidered N = 23 taxonomic group ! geographicregion combinations for latitude, incorporating764 individual species responses, and N = 31

taxonomic group ! region combinations for ele-vation, representing 1367 species responses. Forthe purpose of analysis, the mean shift across allspecies of a given taxonomic group, in a givenregion, was taken to represent a single value (forexample, plants in Switzerland or birds in NewYork State; table S1) (18).

The latitudinal analysis revealed that spe-cies have moved away from the Equator at a

median rate of 16.9 km decade!1 (mean = 17.6km decade!1, SE = 2.9, N = 22 species group !region combinations, one-sample t test versuszero shift, t = 6.10, P < 0.0001). Weighting eachstudy by the "(number of species) in the group !region combination gave a mean rate of 16.6 kmdecade!1. For elevation, there was a median shiftto higher elevations of 11.0 m uphill decade!1

(mean = 12.2 m decade!1, SE = 1.8, N = 30 spe-cies groups ! regions, one-sample t test versuszero shift, t = 7.04, P < 0.0001). Weighting ele-vation studies by "(number of species) gave amean rate of uphill movement of 11.1 m decade!1.

A previous meta-analysis (14) of distribu-tion changes analyzed individual species, ratherthan the averages of taxonomic groups ! regionsthat we used, and also included data on latitu-dinal and elevational shifts in the same analysis(18). It concluded that ranges had shifted towardhigher latitudes at 6.1 km decade!1 and to high-er elevations at 6.1 m decade!1 (14), whereasthe rates of range shift that we found were sig-nificantly greater [N = 22 species groups ! regions,one-sample t test versus 6.1 km decade!1, t =3.99, P = 0.0007 for latitude; N = 30 groups !regions, one-sample t test versus 6.1 m decade!1,t = 3.49, P = 0.002 for elevation (18)]. Ourestimated mean rates are approximately threeand two times higher than those in (14), for

1Department of Biology, University of York, Wentworth Way,York YO10 5DD, UK. 2Biodiversity Research Center, AcademiaSinica, 128 Academia Road, Section 2, Nankang Taipei 115,Taiwan. 3School of Biological and Biomedical Sciences, andInstitute of Hazard, Risk and Resilience, Durham University,South Road, Durham DH1 3LE, UK. 4Centre for Ecology &Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire,OX10 8BB, UK.

*To whom correspondence should be addressed. E-mail:[email protected]

Fig. 1. Relationship between observed and expected range shifts in response to climate change, for (A)latitude and (B) elevation. Points represent the mean responses (TSE) of species in a particular tax-onomic group, in a given region. Positive values indicate shifts toward the pole and to higher ele-vations. Diagonals represent 1:1 lines, where expected and observed responses are equal. Open circles,birds; open triangles, mammals; solid circles, arthropods; solid inverted triangles, plants; solid square,herptiles; solid diamond, fish; solid triangle, mollusks.

19 AUGUST 2011 VOL 333 SCIENCE www.sciencemag.org1024

REPORTS

Chen  et  al.  (Science  2011)  

Climate  change.  Distribu,on  shihs  

European  Environment  Agency  

Species  respond  individually  to  climate  change  

Influence  on  ecological  networks?  

Page 50: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Climate  change.  Distribu,on  shihs  

Enemy escape and species expansion 417

© 2008 The AuthorsJournal compilation © 2008 The Royal Entomological Society, Ecological Entomology, 33, 413–421

were found between populations using different host plants ( Fig. 2b , Mann – Witney, Z = – 0.22, P = 0.827).

Temporal variability in parasitism rate: new vs. long-established populations

Figure 3 shows observed parasitism rate of A. agestis caterpil-lars in four generations over 3 years, at Aston Rowant and Kirkby-on-Bain. Observed parasitism rate did not differ between generation within populations (Aston Rowant: ! 2 = 3.06, P = 0.383 and Kirkby-on-Bain: ! 2 = 2.66, P = 0.447). However, observed para-sitism rate was always higher in the long-established Aston Rowant population than in Kirkby-on-Bain, where colonisation was recent (mean ± SE: 75.0 ± 6.9 Aston Rowant and 33.6 ± 5.4 Kirkby-on-Bain; Mann – Whitney, Z = – 2.31, P < 0.05).

Parasitism rate of Aricia agestis vs. a long established host (Polyommatus icarus)

Sixty-two P. icarus caterpillars from Kirkby-on-Bain and 23 caterpillars from Aston Rowant were collected. Observed parasitism rate differed between the two butterfly species in the newly colonised area at Kirkby-on-Bain ( Fig. 4 , Mann – Whitney, Z = – 2.31, P < 0.05); the small sample size did not allow us to test for differences between species in the long-established pop-ulation at Aston Rowant (only 23 caterpillars of P. icarus were collected). Observed parasitism rate for P. icarus in the newly colonised area was also as high as that observed for A. agestis in the long-established population (mean ± SE: 75.0 ± 6.9 A. agestis in Aston Rowant and 68.0 ± 8.0 P. icarus in Kirkby-on-Bain; P = 0.486).

Figure 5 shows the complex of parasitoid species attacking the larval stage of A. agestis and P. icarus in Aston Rowant (long established) and Kirkby-on-Bain (newly colonised)

populations. Hyposoter notatus was the species responsible for most parasitism of A. agestis in Aston Rowant, but it contributed little to parasitism at Kirkby-on-Bain, where C. astrarches was the main parasitoid. In contrast, P. icarus experienced a high rate of parasitoid attack by H. notatus at Kirkby-on-Bain.

Discussion

Invading insects, and those that are expanding as a result of climate change, may be attacked by fewer parasitoid species and suffer reduced levels of parasitism in newly colonised areas ( Cornell & Hawkins, 1993; Schönrogge et al. , 1995, 1998 ). The results of the present study showed that similar numbers of parasitoid species were attacking A. agestis in newly (five species) and long-established (six species) popula-tions. This is probably because A. agestis parasitoids are not single-host specialists and most of the parasitoid species already occurred far to the north of the distribution of the but-terfly, using alternative hosts such as P. icarus or A. artaxerxes ( Shaw, 1996, 2007, 2008 ). Host recruitment by relatively specialised insect parasitoids seems common when exotic invaders move to an area that contains native congeners ( Keane & Crawley, 2002 ).

Despite the similar species richness of parasitoids in the new part of the range, A. agestis caterpillars nonetheless suffered lower overall parasitism rates compared with caterpillars in the long-established part of the range. They also suffered lower parasitism than did caterpillars of P. icarus , a host species that has been long established in the same northern localities that A. agestis has recently colonised, and also long-established populations of A. artaxerxes in more northern sites (67% para-sitism was recorded by Shaw, 1996 ). This suggests that A. ages-tis has partially escaped from its enemies during its northwards expansion in Britain, and this is not a result of latitudinal pat-terns in parasitism rates.

Fig. 2. Observed parasitism (%) of Aricia agestis caterpillars (i.e. sum of parasitism by all parasitoid species) during the fi rst genera-tion in 2004: (a) populations that differ in the position within the butterfl y range (estab-lished vs. new parts of the range), and (b) populations that differ in the host plant used by the butterfl y ( Helianthemum vs. Geranium / Erodium ). Values are mean + SE and num-bers within bars show sample sizes (numbers of caterpillars collected).

(a) (b)

Established New

0

10

20

30

40

50

60

Obs

erve

d pa

rasi

tism 41

66

Helianthemum Geranium/Erodium

0

10

20

30

40

50

60

3473

Type of population

Menendez  et  al.  (Ecol.  Entomol.  2011)  

Aricia  ages,s    

Page 51: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Climate  change.  Distribu,on  shihs  

Enemy escape and species expansion 417

© 2008 The AuthorsJournal compilation © 2008 The Royal Entomological Society, Ecological Entomology, 33, 413–421

were found between populations using different host plants ( Fig. 2b , Mann – Witney, Z = – 0.22, P = 0.827).

Temporal variability in parasitism rate: new vs. long-established populations

Figure 3 shows observed parasitism rate of A. agestis caterpil-lars in four generations over 3 years, at Aston Rowant and Kirkby-on-Bain. Observed parasitism rate did not differ between generation within populations (Aston Rowant: ! 2 = 3.06, P = 0.383 and Kirkby-on-Bain: ! 2 = 2.66, P = 0.447). However, observed para-sitism rate was always higher in the long-established Aston Rowant population than in Kirkby-on-Bain, where colonisation was recent (mean ± SE: 75.0 ± 6.9 Aston Rowant and 33.6 ± 5.4 Kirkby-on-Bain; Mann – Whitney, Z = – 2.31, P < 0.05).

Parasitism rate of Aricia agestis vs. a long established host (Polyommatus icarus)

Sixty-two P. icarus caterpillars from Kirkby-on-Bain and 23 caterpillars from Aston Rowant were collected. Observed parasitism rate differed between the two butterfly species in the newly colonised area at Kirkby-on-Bain ( Fig. 4 , Mann – Whitney, Z = – 2.31, P < 0.05); the small sample size did not allow us to test for differences between species in the long-established pop-ulation at Aston Rowant (only 23 caterpillars of P. icarus were collected). Observed parasitism rate for P. icarus in the newly colonised area was also as high as that observed for A. agestis in the long-established population (mean ± SE: 75.0 ± 6.9 A. agestis in Aston Rowant and 68.0 ± 8.0 P. icarus in Kirkby-on-Bain; P = 0.486).

Figure 5 shows the complex of parasitoid species attacking the larval stage of A. agestis and P. icarus in Aston Rowant (long established) and Kirkby-on-Bain (newly colonised)

populations. Hyposoter notatus was the species responsible for most parasitism of A. agestis in Aston Rowant, but it contributed little to parasitism at Kirkby-on-Bain, where C. astrarches was the main parasitoid. In contrast, P. icarus experienced a high rate of parasitoid attack by H. notatus at Kirkby-on-Bain.

Discussion

Invading insects, and those that are expanding as a result of climate change, may be attacked by fewer parasitoid species and suffer reduced levels of parasitism in newly colonised areas ( Cornell & Hawkins, 1993; Schönrogge et al. , 1995, 1998 ). The results of the present study showed that similar numbers of parasitoid species were attacking A. agestis in newly (five species) and long-established (six species) popula-tions. This is probably because A. agestis parasitoids are not single-host specialists and most of the parasitoid species already occurred far to the north of the distribution of the but-terfly, using alternative hosts such as P. icarus or A. artaxerxes ( Shaw, 1996, 2007, 2008 ). Host recruitment by relatively specialised insect parasitoids seems common when exotic invaders move to an area that contains native congeners ( Keane & Crawley, 2002 ).

Despite the similar species richness of parasitoids in the new part of the range, A. agestis caterpillars nonetheless suffered lower overall parasitism rates compared with caterpillars in the long-established part of the range. They also suffered lower parasitism than did caterpillars of P. icarus , a host species that has been long established in the same northern localities that A. agestis has recently colonised, and also long-established populations of A. artaxerxes in more northern sites (67% para-sitism was recorded by Shaw, 1996 ). This suggests that A. ages-tis has partially escaped from its enemies during its northwards expansion in Britain, and this is not a result of latitudinal pat-terns in parasitism rates.

Fig. 2. Observed parasitism (%) of Aricia agestis caterpillars (i.e. sum of parasitism by all parasitoid species) during the fi rst genera-tion in 2004: (a) populations that differ in the position within the butterfl y range (estab-lished vs. new parts of the range), and (b) populations that differ in the host plant used by the butterfl y ( Helianthemum vs. Geranium / Erodium ). Values are mean + SE and num-bers within bars show sample sizes (numbers of caterpillars collected).

(a) (b)

Established New

0

10

20

30

40

50

60

Obs

erve

d pa

rasi

tism 41

66

Helianthemum Geranium/Erodium

0

10

20

30

40

50

60

3473

Type of population

Menendez  et  al.  (Ecol.  Entomol.  2011)  

Aricia  ages,s     “Does  range  expansion  leave  enemies  behind?  Bukerfly  pathogen  and  

parasitoid  communi,es  in  response  to  climate  change”  

Page 52: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)
Page 53: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Aricia  ages,s    

Epargyreus  clarus  

Pararge  aegeria  

Page 54: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Aricia  ages,s    

Epargyreus  clarus  

Pararge  aegeria  

!

Page 55: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Summer  2014…..  

Page 56: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Winter-­‐Spring  2015…..  

Page 57: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 58: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)
Page 59: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)
Page 60: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)
Page 61: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Pocock,  Evans  &  Memmok  (Science  2012)  

Species  interac,ons:  Meta-­‐networks  

Page 62: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Knight  et  al.  (Nature  2005)  

Spa,al  scales:  From  species  to  ecosystem  func,ons  &  services  

Indirect  interacIons:  PollinaIon  near  ponds  

Page 63: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

INDIRECT  EFFECTS                    

Knight  et  al.  (Nature  2005)  

NEED  FOR  A    NETWORK  

PERSPECTIVE  

Spa,al  scales:  From  species  to  ecosystem  func,ons  &  services  

Indirect  interacIons:  PollinaIon  near  ponds  

Page 64: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

INDIRECT  EFFECTS                    

Knight  et  al.  (Nature  2005)  

NEED  FOR  A    NETWORK  

PERSPECTIVE  

Spa,al  scales:  From  species  to  ecosystem  func,ons  &  services  

NEED  FOR  A    LANDSCAPE  APPROACH  

CROSS-­‐HABITAT  INTERACTION  

Indirect  interacIons:  PollinaIon  near  ponds  

Page 65: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Landscape  restora,on:  Implica,ons  for  stability  

Montoya,  Rogers  &  Memmok  (Trends  Ecol  &  Evol.  2012)  

Page 66: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Montoya,  Rogers  &  Memmok  (Trends  Ecol  &  Evol.  2012)  

Landscape  restora,on:  The  more  the  beker?  

-­‐  Low  spaIal  overlap  of  different  ecosystem  services  (Eigenbrod  et  al.,  J.  Appl.  Ecol.  2010)  

 -­‐  MulI-­‐habitat  use  of  many  species  

Page 67: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Landscape  Food-­‐Webs  Projects  (NERC  Funding)  

Jane  Memmor  Steve  Gregory  Daniel  Montoya  Talya  Hacker  Nancy  Davis    Simon  Pors  Anna  Scor      Jason  Tylianakis    

Page 68: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Recovery  dynamics  

What's  the  pathway  of  recovery?  

Page 69: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Thomas  et  al.  (Science  2009)  

Recovery  dynamics  

What's  the  pathway  of  recovery?  

Maculinea  arion  

Page 70: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Bullock  et  al.  (Trends  Ecol.  &  Evol.  2011)  

What's  the  pathway  of  recovery?  

Recovery  dynamics  

Page 71: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Montoya,  Rogers  &  Memmok  (Trends  Ecol.  &  Evol.  2012)  

Recovery  dynamics  

What's  the  pathway  of  recovery?  

Page 72: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Remember  the  model?  

Lurgi,  M.  et  al  (Theore,cal  Ecology,  In  press)    

///  

Page 73: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 74: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 75: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 76: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 77: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 78: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

The  model:  Simula,ng  restora,on  

Page 79: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

REFERENCE  

The  model:  Simula,ng  restora,on  

Page 80: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

REFERENCE  

The  model:  Simula,ng  restora,on  

Page 81: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Stability  

Structure  

TIME  

REFERENCE  

RECOVERY  DYNAMICS  

The  model:  Simula,ng  restora,on  

Page 82: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model  results.  Abundance  &  Shannon  

Page 83: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

20%  

Model  results.  Abundance  &  Shannon  

Page 84: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

20%   50%  

Model  results.  Abundance  &  Shannon  

Page 85: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

20%   50%   80%  

Model  results.  Abundance  &  Shannon  

Page 86: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

20%   50%   80%  

éDestruc,on/Restora,on  

Model  results.  Abundance  &  Shannon  

Page 87: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

20%   50%   80%  

éDestruc,on/Restora,on  

20%   50%   80%  

éDestruc,on/Restora,on  

Model  results.  Abundance  &  Shannon  

Page 88: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model  results.  Network  &  Stability  

Ini,al  recovery:  More  unstable  

Page 89: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Model  results.  Conclusions  

•  Magnitude  of  perturba,on  affects  recovery  (the  higher  the  longer):  •  No  change  in  species  richness,  but  abundance  takes  longer  to  recover  •  Shannon  index  takes  longer  to  recover:  same  species  but  more  even  

à  Parerns  of  dominant  species  observed  in  reference  communiIes  are  diluted  

•  Temporal  stability  takes  longer  to  recover  the  larger  the  destrucIon    

•  IniIal  stages  of  restoraIon:    •  Many  properIes  show  contrasIng  parerns  (e.g.  increase  and  

decrease),  this  reflecIng  transient  dynamics  à  Need  for  long-­‐term  monitoring  

Page 90: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Restora,on  of  tropical  seed  dispersal  networks  

Page 91: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Restora,on  of  tropical  seed  dispersal  networks  

!15  years   25  years   57  years  

Page 92: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

15  years  old  of  restora,on  

Page 93: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

15  years  old  of  restora,on  

Page 94: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

25  years  old  of  restora,on  

Page 95: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

25  years  old  of  restora,on  

Page 96: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

57  years  old  of  restora,on  

Page 97: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

57  years  old  of  restora,on  

Page 98: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Restora,on  of  tropical  seed  dispersal  networks  

Plant-­‐Seed  dispersal  network  

!

Page 99: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Restora,on  of  tropical  seed  dispersal  networks  

15  years   25  years   57  years  

!!!

Page 100: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Restora,on  of  tropical  seed  dispersal  networks  

Species  richness  

Linkage  density  

Connectance   Weighted  nestedness  

H2’   Modularity   Robustness   Shannon  index  

15  years   34   1.21   0.14   13.6   0.51   -­‐   0.66   3.7  

25  years   63   2.44   0.15   26.9   0.3   -­‐   0.74   5  

57  years   33   1.27   0.15   15.4   0.42   0.51   0.66   3.7  

Ribeiro,  et  al  (Restora,on  Ecology,  Invited  resubmission)    

!

Page 101: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

!

Restora,on  of  tropical  seed  dispersal  networks  

Species  richness  

Linkage  density  

Connectance   Weighted  nestedness  

H2’   Modularity   Robustness   Shannon  index  

15  years   34   1.21   0.14   13.6   0.51   -­‐   0.66   3.7  

25  years   63   2.44   0.15   26.9   0.3   -­‐   0.74   5  

57  years   33   1.27   0.15   15.4   0.42   0.51   0.66   3.7  

Link  to  theore,cal  results  

Ribeiro,  et  al  (Restora,on  Ecology,  Invited  resubmission)    

Page 102: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Talk  outline  

1.   Understanding  complex  communi,es    -­‐  Structure-­‐Stability    -­‐  Structure-­‐Func,oning  -­‐  Structure-­‐Dynamics  

2.  Responses  to  perturba,ons  &  recovery    3.  Future  direc,ons  

Page 103: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

‘Networks  of  networks’  

Temporal  dynamics  

Quan,fying  mul,ple  func,ons  

Species  interac,ons  

Real-­‐world  ecosystems  

Quan,fying  stability  

Biodiversity-­‐  Ecosystem  Func,oning  

Food  web  ecology  

Complexity-­‐Stability  

Restora,on  ecology  

Page 104: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

‘Networks  of  networks’  

Temporal  dynamics  

Quan,fying  mul,ple  func,ons  

Species  interac,ons  

Real-­‐world  ecosystems  

Quan,fying  stability  

Biodiversity-­‐  Ecosystem  Func,oning  

Food  web  ecology  

Complexity-­‐Stability  

Restora,on  ecology  

Page 105: BC3 Seminars: "Species interaction networks, global change and restoration" Dr. Daniel Montoya (2015-04-18)

Jane  Memmor  (UK)  Marian  Yallop  (UK)  Sol  Milne,  Sian  de  Bell  (UK)  Rothamstead  Research  (North  Wyke)  Miguel  Lurgi  (Australia)  Jose  M.  Montoya  (France)  Lucy  Rogers  (UK)  Sara  Varela  (Germany)  Hedvig  K.  Nenzen  (Canada)  Maaike  De  Jong  (UK)  Gary  Barker  (UK)  Jo  Morten,  Emy  Topp  (UK)  Steve  Gregory  (UK)  Talya  Hacker  (UK)  Nancy  Davis,  Rose  Archer  (UK)  Simon  Pors  (UK)  Anna  Scor  (UK)  Jason  Tylianakis  (New  Zealand)  Fernanda  Ribeiro  da  Silva  (Brazil)  

Thanks  

Rafael  Furtado  (Brazil)  Marco  Aurelio  Pizo  (Brazil)  Ricardo  Ribeiro  Rodrigues  (Brazil)  David  Moreno-­‐Mateos  (Spain)  Holly  Jones  (USA)  Karen  Holl  (USA)  Jose  M.  Rey  (Spain)  Peter  Jones  (USA)  Paula  Meli  (ArgenIna)  Michelle  McCrackin  (Sweden)  Ed  Barbier  (USA)