The database contains information on brain size, body mass, life-history traits and development mode for a total of 620 bird species. The taxonomy follows Jetz et. al. (2012). For life-history the database includes information for the following six variables: clutch size, egg size, incubation period, fledging age, maximum longevity; as well as development mode (altricial, semialtricial, precocial and semiprecocial). Additionally, in most cases there is information about the origin or the sampled specimen (captivity vs wild origin), quality control, and a nominal estimate of the sample size, all referring to the maximum longevity data.

The compiled data for brain size comes from the sources listed in reference 1. The data for body size and life history variables were collected from Iwaniuk and Nelson (2003), Myhrvold et. al., (2015), and Tacutu et. al., 2013. As no single database had complete information available for the variables of interest, we merged the information between databases in order to get the most complete set of variables for each species.

References:

1. Iwaniuk, A. N. & Nelson,  J.E. (2003) Can. J. Zool. 81: 1913-1928; Armstrong, E. & Bergeron, R. (1985) Relative brain size and metabolism in birds. Brain Behav. Evol. 26: 141-153; Boire, D. & Baron, G. (1994) Allometric comparison of brain and main subdivisions in birds. J. Brain Res. 35: 4966; Garamszegi et al (2002) Proc. R. Soc. B. 269, 961-967; Garamszegi et al (2005) Proc. R. Soc. B. 272, 159-166; Mlikovsky, J. (1989) Brain size in birds 3: Columbiformes through Piciformes; Mlikovsky, J. (1989) Brain size in birds 2: Falconiformes through Gaviiformes; Mlikovsky, J. (1989) Brain size in birds 1: Tinamiformes through Ciconiiformes; Mlikovsky, J. (1990) Brain size in birds 4: Passeriformes; Crile, G. & Quiring, D.P. (1940) A record of the body weight and certain organ and gland weight of 3690 animals. Ohio J. Sci. 40: 219-259; Burish, M.J.,  Kueh, H.Y. & Wang, S-H. S. (2002) Brain architecture and social complexity in modern and ancient birds. Brain Behav. Evol. 63: 107-124; Ferran Sayol, Joan Maspons, Oriol Lapiedra, Andrew N. Iwaniuk, Tama´s Szekely & Daniel Sol (2016). Environmental variation and the evolution of large brains in birds. Nature Communications. 7:13971
2. Iwaniuk, A. N., and J. E. Nelson. 2003. Developmental differences are correlated with relative brain size in birds: a comparative analysis. Can. J. Zool. 81:1913–1928.
3. Jetz, W., G. H. Thomas, J. B. Joy, K. Hartmann, and A. O. Mooers. 2012. The global diversity of birds in space and time. Nature 491:444–448
4. Myhrvold NP, Baldridge E, Chan B, Sivam D, Freeman DL, Ernest SKM. 2015 An amniote life-history database to perform comparative analyses with birds , mammals , and reptiles. Ecology 96, 3109
5. Tacutu R, Craig T, Budovsky A, Wuttke D, Lehmann G, Taranukhe D, Costa J, Fraifeld VE, de Magalhães P. 2013 Human Ageing Genomic Resources : Integrated databases and tools for the biology and genetics of ageing. Nucleic Acids Res. 41, 1027–1033. (doi:10.1093/nar/gks1155)

The databse was filtered based on the quality of the longevity data prior to analyses.