Floral traits often display sexual dimorphism in insect-pollinated dioecious plant species, with male individuals typically being showier than females. While this strategy is theorized to be optimal when pollinators are abundant, it might represent a risk when they become scarce, because the disproportionately high number of visits on the most attractive sex, males, might preclude efficient pollen transfer from males to females. Here, the effect of sexual dimorphism on pollination efficiency was assessed in experimental arrays of dioecious Silene dioica that were exposed to one frequent visitor of the species, Bombus terrestris, and that differed in the magnitude of sexual dimorphism for either flower number or flower size. We measured the number of visits on female plants, on female flowers and on the number of female flowers visited after a male flower, as well as the number of pollen grains deposited per stigma.

Column names and contents of the 3 sub-datasets are described below

-> DataSilene_Plants (one line = one plant)

Nsession    Name of the experimental session (3 treatments * 8 replicas = 24 sessions, named A to X)                    
Date    Day the session was performed                    
Hive    Hive identity                    
sex    Plant sex (F : female, M : male)                    
Dim    Are plants sexually dimorphic for flower number or flower size in the session ? (Dim : Yes, NoDim : No)                    
DimNumber    Are plants sexually dimorphic for flower number in the session ? (Dim : Yes, NoDim : No)                    
DimSize    Are plants sexually dimorphic for flower size in the session ? (Dim : Yes, NoDim : No)                    
Ttt    Treatment (Number : number dimorphism, Size : size dimorphism, Control : no dimorphism)                    
ID    Plant identity                    
nflo    Flower number at the time of the experiment                    
wflo1    Width of flower number 1 (mm)                    
wflo2    Width of flower number 2 (mm)                    
wflo3    Width of flower number 3 (mm)                    
wflo4    Width of flower number 4 (mm)                    
wflo5    Width of flower number 5 (mm)                    
meansizeind    Mean flower width                    
VisitPerPlant    Number of bumblebee visits per plant                    
VisitPerFlower    Estimate of the number of bumblebee visits per flower (VisitPerPlant / nflo)

-> DataSilene_Bumblebees (one line = one sequence of ten visits by a bumblebee)                        

Nsession    Name of the experimental session (3 treatments * 8 replicas = 24 sessions, named A to X)                    
Date    Day the session was performed                    
Hive    Hive identity                    
Dim    Are plants sexually dimorphic for flower number or flower size in the session ? (Dim : Yes, NoDim : No)                    
DimNumber    Are plants sexually dimorphic for flower number in the session ? (Dim : Yes, NoDim : No)                    
DimSize    Are plants sexually dimorphic for flower size in the session ? (Dim : Yes, NoDim : No)                    
Ttt    Treatment (Number : number dimorphism, Size : size dimorphism, Control : no dimorphism)                    
nflosession    Total number of flowers available in the session (male + female)                    
nfloFsession    Total number of female flowers available in the session                    
Order    Flying order  (order in which bumblebees exited the hive)                    
S1    Sex of visited flower number 1                    
S2    Sex of visited flower number 2                    
S3    Sex of visited flower number 3                    
S4    Sex of visited flower number 4                    
S5    Sex of visited flower number 5                    
S6    Sex of visited flower number 6                    
S7    Sex of visited flower number 7                    
S8    Sex of visited flower number 8                    
S9    Sex of visited flower number 9                    
S10    Sex of visited flower number 10                    
NbTotInd    Number of visited plants                    
NbFF    Number of visited female flowers                    
NbPF    Number of visited female plants                    
NbFM    Number of visited male flowers                    
NbPM    Number of visited male plants                    
ShiftFM    Number of shifts from a female to a male flower                    
ShiftMF    Number of shifts from a male to a female flower                    
NoShift    Number of transitions between flowers that do not involve a change in visited sex                     
NbFpostM    Number of female flowers visited after the insect had visited at least one male flower (estimate of the number of potentially pollinating visits)                    
NbFbef    Number of female flowers visited before any male in the sequence                    

-> DataSilene_Pollen (one line = one female plant)

Nsession    Name of the experimental session (3 treatments * 8 replicas = 24 sessions, named A to X)                    
Date    Day the session was performed                    
Hive    Hive identity                    
Dim    Are plants sexually dimorphic for flower number or flower size in the session ? (Dim : Yes, NoDim : No)                    
DimNumber    Are plants sexually dimorphic for flower number in the session ? (Dim : Yes, NoDim : No)                    
DimSize    Are plants sexually dimorphic for flower size in the session ? (Dim : Yes, NoDim : No)                    
Ttt    Treatment (Number : number dimorphism, Size : size dimorphism, Control : no dimorphism)
ID    Plant identity
nflo    Flower number at the time of the experiment
VisitPerPlant    Number of bumblebee visits per plant
VisitPerFlower    Estimate of the number of bumblebee visits per flower (VisitPerPlant / nflo)
MeanPollen    Mean number of pollen grains deposited per stigma