We include one dataset with demographic data for birds, called RCW_demo_data. Each row in this csv file represents an individual x year combination, and columns include information about individual and territory characteristics in that year, as well as various vital rates. For reproductive vital rates, we include these rates only for female breeders. Thus, reproductive vital rates such as “successfirstnest” will be NA (indicating missing data) for all males and for female non-breeders. Each row includes a climate reference number (“clim.group”) that allows the demographic data to be matched with the climate data in the climate files (see below for more description about these climate data). Below we list each column individually.

Year: year in which data were collected

Surtonext: did this individual survive to the next breeding season (1) or not (0)?

Nohelp: how many helpers were present in this territory?

Firstnestattempt_bin: did this breeding female initiate a nest in that year’s breeding season? 1 indicates yes, 0 indicates no.

Morenestattempt_bin: did this breeding female initiate more than one nest in that years breeding season? 1 indicates yes, 0 no.

Fledgedfirstnest: how many fledged from the first nest.

Fledgedlaternest: how many fledged from any later nests.

Eggsfirstattempt: how many eggs in the first nest.

Eggslaterattempt: how many eggs in the first nest.

Clim.group: a grouping variable that matches the clim.group variable in the climate datasets. Note that the demographic data contains a space, the climate datasets a period, but SH 146 is the same climate grouping as SH.146.

Site: one of SH, EG, or CL, representing Sandhills, Eglin, or Camp Lejeune

Numericage: age of the bird

Binned status: one of Breeder, Helper or Floater (B, H, or F).

Sex: F or M

Numericmalemateage: age of the male breeder which which a female bred. Only recorde for breeding females.

Successfirstnest_bin: was the first nest successful? 1 indicates yes, 0 no.

Frsurvivingfirst: what fraction of eggs survived to fledging from the first nest?Successmorenest_bin: were any later (i.e., 2nd or later) nests successful? 1 indicates yes, 0 no.

Frsurvivinglater: what fraction of eggs survived to fledging from all later nests?

We have included five datasets corresponding to the five climate variables. The name of the csv file indicates the climate variable that the dataset contains. Each dataset contains information on the date, the climate group (clim.grp, corresponds to the climate groups in the demographic dataset), and the value of the climate signal for that date. Units are indicated in the main text for this paper.

The FST-heterozygosity outlier approach has been a popular method for identifying loci under balancing and positive selection since Beaumont and Nichols first proposed it in 1996 and recommended its use for studies sampling a large number of independent populations (at least 10). Since then, their program FDIST2 and a user-friendly program optimized for large datasets, LOSITAN, have been used widely in the population genetics literature, often without the requisite number of samples. We observed empirical datasets whose distributions could not be reconciled with the confidence intervals generated by the null coalescent island model. Here, we use forward-in-time simulations to investigate circumstances under which the FST-heterozygosity outlier approach performs poorly for next-generation single-nucleotide polymorphism (SNP) datasets. Our results show that samples involving few independent populations, particularly when migration rates are low, result in distributions of the FST-heterozygosity relationship that are not described by the null model implemented in LOSITAN. In addition, even under favorable conditions LOSITAN rarely provides confidence intervals that precisely fit SNP data, making the associated p-values only roughly valid at best. We present an alternative method, implemented in a new R package named fsthet, which uses the raw empirical data to generate smoothed outlier plots for the FST-heterozygosity relationship.