Supplement 2. Raw phenological, life history, and ecological breadth data.

File List Adult_Survival.csv (MD5: b05142c8e4f507949a0de4448fd1b268) Arrival_Date.csv (MD5: cbbf8fa18b115e9f3c05fd70f5896150) Biogeography.csv (MD5: 627fe84e1ffb74d55065f06abc2cec12) Breeding_Date.csv (MD5: 1ab82e4d46ff6703251af676248fa1a8) Brood_Number.csv (MD5: 6cda71ced7d80623f71bddd506904632) Clutch_Size.csv (MD5: 5e1fd440ef3eea8046ce1e7eddc64735) Diet_Breadth.csv (MD5: ebc8b7663bd97a86f2b64a84b12033ec) Egg_Mass.csv (MD5: 00af1875f709dfe307fa4b688cd716b6) Foraging_Behaviour_Breadth.csv (MD5: 34d2fec478134a29c3143b8de278af85) Habitat_Breadth.csv (MD5: 32ed27214f2580fa521f9661807e67dc) Nest_Site_Breadth.csv (MD5: 96ac8ff7223e5e623d2449cd1a897744) Description These files contain species- and location-specific information for each of the ecological traits that we investigated. <br> Columns found in all files are as follows: Comparison: Independent comparison number, sequentially numbered, following the taxonomic order of Gill and Donsker (2010). Dominance: Whether species was classified as dominant or subordinate based on outcome of aggressive interactions (see Supplement 1 for details). Record: Unique record number for each site, year, or study from which data on a pair was gathered. Genus: Taxonomic genus of focal species, following Gill and Donsker (2010). Species: Focal species, following Gill and Donsker (2010). Mass: Mean mass values for each species. Location: Region where data were collected according to original references. Reference: Original reference from which ecological data were collected. Columns unique to Arrival_Date.csv and Breeding_Date.csv Julian.Date: Julian date calculated from first arrival or first egg dates in original reference (mean if original reference spanned multiple years). Date: Original date of first arrival or first egg in original reference (mean if original reference spanned multiple years). Details: how first arrival or egg date was defined in original reference. Columns unique to Clutch_Size.csv Clutch.Size: Clutch size from original reference (mean if original reference spanned multiple years). Columns unique to Egg_Mass.csv Calculated.Fresh.Egg.Mass: Egg mass as calculated in original reference. Columns unique to Brood_Number.csv Number.of.Broods.per.Year: Most common number of broods (excluding renests) produced annually for each species, from original reference. Columns unique to Survival.csv Annual.Survivorship: Average probability of a breeding-age bird surviving from one year to the next from original reference (mean if original reference spanned multiple years). N: Number of individuals used to estimate annual survivorship. Notes: Method used to estimate annual survivorship and which individuals were included in original reference. Columns unique to Diet_Breadth.csv, Foraging_Behaviour_Breadth.csv, Nest_Site_Breadth.csv, and Habitat_Breadth.csv X.Diversity: Calculated Shannon-Weaver index of diversity for trait of interest (mean if original reference spanned multiple years). X.Richness: Number of unique categories of the trait of interest observed in the original reference (mean if original reference spanned multiple years). N: Number of individuals included in original reference Notes: How the ecological trait of interest was defined in the original reference. Columns unique to Biogeography.csv Breeding.Range.Size: Size of breeding range within Americas in km2 as calculated in BirdLife International and NatureServe (2011) using a Lambert Azimuthal Equal Area projection. Wintering.Range.Size: Size of wintering range within Americas in km2 as calculated in BirdLife International and NatureServe (2011) using a Lambert Azimuthal Equal Area projection. Breeding.Range.Latitude: Latitude of the centroid of breeding range within Americas in degrees as calculated from maps in BirdLife International and NatureServe (2011). Wintering.Range.Latitude: Latitude of the centroid of wintering range within Americas in degrees as calculated from maps in BirdLife International and NatureServe (2011). Breeding.Range.Longitude: Longitude of the centroid of breeding range within Americas in degrees as calculated from maps in BirdLife International and NatureServe (2011). Wintering.Range.Longitude: Longitude of the centroid of wintering range within Americas in degrees as calculated from maps in BirdLife International and NatureServe (2011). Migration.Distance: Distance in km between centroid of the breeding range and the centroid of the wintering range, estimated using an online calculator (http://www.csgnetwork.com/gpsdistcalc.html). <br>