Contribution of traits, phenology, & phylogenetic history to plant-pollinator network structure

Scott Chamberlain Simon Fraser University

http://bit.ly/scott_canpolin

Thanks to!

• Elizabeth Elle

• Jana Vamosi

• Ralph Cartar

• Sarah Semmler

• Anne Worley

• And many more that provided data…

Species in communities form networks

Patterns often similar among networks

Pla

nts

Pollinators

Structure matters

Bascompte&Jordano2007AREES

What drives network structure?

Traits Body size

Phenology

Emergence date Or

Seasonal activity

Phylogenetic History

Traits

Phenology

Phylogenetic History

Study sites

Phylogeny

Plants Pollinators

Species level metrics

• Degree

• Specialization (accounts for interaction intensity)

• Within module degree

• Among module connectivity

Traits - Pollinators

• Nest location: above/below ground - NS

• Nest type: excavator/renter - NS

• Parasitic: yes/no - NS

Traits - Pollinators

• Nest location: above/below ground - NS • Nest type: excavator/renter - NS • Parasitic: yes/no - NS • Social: solitary/social –

– Within module degree: social (module hubs), solitary (peripherals)

– Among module connectivity: social (connectors), solitary (peripherals)

– Degree: social (higher), solitary (lower)

• Body size – larger spp. w/ larger degree

Traits - Plants

• Breeding system

– Gynomonoecious: less specialized, higher degree

– Hermaphrodites: more specialized, lower degree

Traits - Plants

• Breeding system

– Gynomonoecious: less specialized, higher degree

– Hermaphrodites: more specialized, lower degree

• Growth form

– Herbaceous: lower within module degree

– Woody: higher within module degree

Traits - Plants

• Breeding system – Gynomonoecious: less specialized, higher degree – Hermaphrodites: more specialized, lower degree

• Growth form – Herbaceous: lower within module degree – Woody: higher within module degree

• Flower symmetry: – Bilateral: lower within module degree, lower degree – Radial: higher within module degree, higher degree

• Flower size: smaller flowers higher within module degree

Network level

network structure ~

FDisPO + FDisPL + MPDPO + MPDPL

Network level

network structure ~

FDisPO + FDisPL + MPDPO + MPDPL

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Pollinator FDis

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Pollinator FDis

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Pollinator Functional Trait Dispersion

Conclusion • Species level

– Sociality important in pollinators

– Mating systems, flower symmetry & growth form important in plants

• Network level

– At network level, pollinator functional diversity w/ modularity & connectance

– Pollinator traits bigger drivers of network structure relative to plants

Phenology

• Species vary in when they start flowering (plants) and start flying (pollinators)

• Variation among species can lead to changes in network structure

HLG HLU OKG OKU SOG SOU

WLG WLU cr1 cr2 fs1 fs2

go1 go2 mm1 mm2 mz1 mz2

sm1 sm2 AG BB−1 BB−2 BI

CF−1 CF−2 CV DP LSCR OM

PS−1 PS−2 TH

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Julian day (days since 1 Jan)

Phenology is associated with structures

Robustness differs among groups Plants Pollinators

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Phylogenetic tree shape

• Shape easily measured

• Metrics represent whether

– Branching events recent or old

– Branching events even across tree, or some groups speciate more than others

• Shape could influence who interacts with who

Shape correlated with network structure

Simulations suggest a causal link

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Tree Balance

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Unbalanced

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Node distribution

Nodes near root

Nodes near tips

Tree balance Distribution of nodes

Number of species (network size)

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Traits

Phenology

Phylogenetic History

Thanks to

• Elizabeth Elle

• Jana Vamosi

• Ralph Cartar

• Sarah Semmler

• Anne Worley

Silhouettes: Phylopic.org http://phylopic.org/image/070c78bc-e075-4098-a66b-fca2f02680ea/