Offspring are cheap for ectotherms

Data to test hypotheses that (i) energy investment into eggs differs between egg-laying vertebrates, with birds (endotherms) investing significantly more than reptiles, amphibians, and fish (ectotherms) and that (ii) such investment depends on species body size. Source: Add-my-Pet database [PLoS Comput Biol 14(5): e1006100].