Abstract
Testosterone plays a critical role in mediating fitness -related traits in many species. Although it is highly responsive to environmental and social conditions, evidence from several species show a heritable component to its individual variation. Despite the known effects that in utero testosterone exposure have on adult fitness, the heritable component of individual testosterone variation in fetuses is mostly unexplored. Furthermore, testosterone has sex -differential effects on fetal development, i.e., a specific level may be beneficial for male fetuses but detrimental for females, producing sexual conflict. Such sexual conflict may be resolved by the evolution of a sexspecific genetic architecture of the trait. Here, we quantified fetal testosterone levels in a wild species, freeranging nutrias ( Myocastor coypus ) using hair -testing and estimated testosterone heritability between parent and offspring from the same and opposite sex. We found that in utero accumulated hair testosterone levels were heritable between parents and offspring of the same sex. Moreover, there was a low additive genetic covariance between the sexes, and a low cross -sex genetic correlation, suggesting a potential for sex -specific trait evolution, expressed early on, in utero.
| Original language | English |
|---|---|
| Article number | 105525 |
| Number of pages | 8 |
| Journal | Hormones and Behavior |
| Volume | 161 |
| Early online date | 6 Mar 2024 |
| DOIs | |
| Publication status | Published - May 2024 |
Bibliographical note
We are grateful to Devorah Matas for her devoted support. We thank KKL-JNF for funding the nutria project and supporting the Hula Research Center. We wish to thank our collaborators from previous work, Prof. Uri Shanas and Prof. Rachel Ben-Shlomo for thoughtful discussions. We also wish to thank our undergraduate student assistants and volunteers, particularly Ester Shavalian, Or Danino, Noam Noylander and Nour Daief, all members of the Koren lab and Anat Levi and the Vortman lab for their support throughout the project.This work was supported by the Jewish National Fund - Keren Kayemeth LeIsrael (grant no. 90-50-000-17), and Israel Science Foundation (grant no. 153/23).