A dataset of ovariole number from more than 2,000 insect species

The number of offspring an organism can produce is a key component of its evolutionary fitness and life-history. This number differs widely between organisms, and its variation is the foundation for several hypotheses about life-history evolution, including the prediction that there is an evolutionary trade off between the number of offspring and their size. In insects, the number of egg-producing compartments in the ovary, called ovarioles, has been used as a proxy for potential offspring number in the study of life-history. Here we present a database of 3,355 descriptions of insect ovariole number, with records for 2,103 unique insect species from 28 hexapod orders. The dataset includes insects with a total adult ovariole number of 1 as well as insects with more than 10,000 ovarioles. We created this database by searching for descriptions of insect ovaries from the primary literature. We matched the taxa in this database to the currently accepted scientific names in taxonomic and genetic databases, which will facilitate the use of this data for testing hypotheses in offspring number evolution.