Read-me file to accompany 'Hybrid Chickadees are Deficient in Learning and Memory' accepted in Evolution, February 2018. Authors: Michael A. McQuillan*, Timothy C. Roth II, Alex V. Huynh, Amber M. Rice *corresponding author: michaelmcquillan5@gmail.com This read-me file describes the variables contained in each of the data files submitted to accompany this manuscript. File: Dryad.Scripts.R Description: Representative R scripts and code for each behavioral analysis. Comments about code are made using hashmarks (#). File: ProblemSolving.csv Description: Contains behavioral data for birds that performed the novel problem-solving task. Subject = Unique ID for each individual bird. Structure.Q = The admixture proportion given by the program STRUCTURE, corresponding to the proportion of an individual's genome derived from Carolina chickadees (based on genotypes from 10 SNP-RFLP markers). Ancestry.Category = The ancestry category assigned to each bird (BCCH=Black-capped chickadee, CACH=Carolina chickadee, HYCH=Hybrid chickadee). Ancestry.Continuous = A continuous measure of species ancestry, calculated by subtracting 0.5 from the STRUCTURE admixture proportion, and then taking the absolute value. Mass = Body mass in grams for each individual. Ancestry.Parental = Black-capped and Carolina birds are combined into a 'Pure' species category, while hybrids comprise the 'Hybrid' category. Sex = Male or Female Season = Time of year the bird was tested on the problem-solving task. Spring=March-May. Summer=June-August. Fall=September-November. Winter=December-February. At.Least.One.Solve = Whether the bird solved the problem at least once (of two total trials) - Yes or No. At.Least.One.Binary = 0=bird did not solve the problem at least once. 1=bird solved the problem at least once. PreTrial.Latency = Latency in seconds for the bird to take the worm from the problem-solving apparatus during the pre-trial control. File: AssociativeLearningSpatialTask.csv Description: Contains behavioral data for birds that performed the associative learning spatial task. Subject = Unique ID for each individual bird. Structure.Q = The admixture proportion given by the program STRUCTURE, corresponding to the proportion of an individual's genome derived from Carolina chickadees (based on genotypes from 10 SNP-RFLP markers). Ancestry.Category = The ancestry category assigned to each bird (BCCH=Black-capped chickadee, CACH=Carolina chickadee, HYCH=Hybrid chickadee). Ancestry.Continuous = A continuous measure of species ancestry, calculated by subtracting 0.5 from the STRUCTURE admixture proportion, and then taking the absolute value. Sex = Male or Female. Season = Time of year the bird was tested on the associative learning spatial task. Spring=March-May. Summer=June-August. Fall=September-November. Winter=December-February. Day = Testing day for associative learning spatial task (2 through 10). Score = The number of inspections (craft pom-pom balls removed) before the bird found the worm. Prior.Experience = Whether the bird had previously experienced feeding from the caching array as part of a separate pilot experiment, before performing the associative learning spatial task (Yes or No). File: BodyCondition.csv Description: Contains morphological data for each individual bird used to calculate and compare the 'Scaled Mass Index' (a measure of body condition). Individual = Unique ID for each individual bird. Mass = Body mass in grams for each individual. Tarsus = Tarsus length in millimeters for each bird. Structure.Q = The admixture proportion given by the program STRUCTURE, corresponding to the proportion of an individual's genome derived from Black-capped chickadees (based on genotypes from 10 SNP-RFLP markers). Ancestry = The ancestry category assigned to each bird (BCCH=Black-capped chickadee, CACH=Carolina chickadee, HYCH=Hybrid chickadee). File: Structure_Input.txt Description: = Tab-delimited file for input into the program STRUCTURE. Contains genotypes at 10 SNP-RFLP markers for individuals from across the hybrid zone in Pennsylvania. SNP-RFLP markers are described in McQuillan et al. 2017 Conserv. Genet. Resour. 9:261–264. Column 1 = Unique ID for each individual bird. Column 2 = Population of origin for each bird. 1=Franklin county, NY. 2=Ulster County, NY. 3=Carbon County, PA. 4=Carbon County, PA. 5=Northampton County, PA. 6=Northampton County, PA. 7=Northampton County, PA. 8=Bucks County, PA. 9=Bucks County, PA. 10=St. Charles County, LA. Remaining Columns = Diploid genotypes at 10 SNP loci. A single individual's multi-locus genotype is contained within a single row. 001=A. 002=C. 003=G. 004=T. Loci are named as in McQuillan et al. 2017, and ordered from left to right as: c0p303, c0p356, c0p373, c0p628, c0p283, c0p251, c0p238, c0p184, c0p171, c0p183. Missing data denoted as -9. STRUCTURE was run using the admixture model and correlated allele frequencies. We specified 100,000 burn-in steps and 200,000 MCMC repetitions with a specified K of 2.