@article{05dd7a25afdd43ef987ebefdc4048431,
title = "Mechanisms of Convergent Egg Provisioning in Poison Frogs",
abstract = "Parental provisioning of offspring with physiological products (nursing) occurs in many animals, yet little is known about the neuroendocrine basis of nursing in non-mammalian species. Within amphibians, maternal provisioning has evolved multiple times, with mothers of some species feeding unfertilized eggs to their developing offspring until tadpoles complete metamorphosis [1–3]. We conducted field studies in Ecuador and Madagascar to ask whether convergence at the behavioral level provides similar benefits to offspring and relies on shared neural mechanisms in dendrobatid and mantellid poison frogs. At an ecological level, we found that nursing allows poison frogs to provide chemical defenses to their tadpoles in both species. At the neural level, nursing was associated with increased activity in the lateral septum and preoptic area, demonstrating recruitment of shared brain regions in the convergent evolution of nursing within frogs and across vertebrates [4]. In contrast, only mantellids showed increased oxytocin neuron activity akin to that in nursing mammals [5], suggesting evolutionary versatility in molecular mechanisms. Our findings demonstrate that maternal provisioning provides similar potential benefits to offspring and relies on similar brain regions in poison frog species with convergently evolved toxicity and maternal care. Video Abstract: [Figure presented] Maternal provisioning has evolved multiple times in amphibians, including in South American and Malagasy poison frogs. Field studies in Ecuador and Madagascar by Fischer, Roland et al. reveal that maternal care facilitates toxin provisioning and relies on similar brain regions in these clades with convergently evolved toxicity and maternal care.",
keywords = "alkaloids, chemical defense, Dendrobatidae, egg provisioning, Mantellidae, oxytocin, parental care, poison frogs, preoptic area",
author = "Fischer, {Eva K.} and Roland, {Alexandre B.} and Moskowitz, {Nora A.} and Charles Vidoudez and Ndimbintsoa Ranaivorazo and Tapia, {Elicio E.} and Trauger, {Sunia A.} and Miguel Vences and Coloma, {Luis A.} and O'Connell, {Lauren A.}",
note = "Funding Information: We would like to thank Mar{\'i}a Dolores Guarderas (Wikiri) for support in Ecuador, Joshua Nelson for help with R code, and Deborah Gordon, the members of the O'Connell lab, and two anonymous reviewers for comments on the manuscript. We thank Roberto Marquez for producing the phylogeny in Figure 1. Work in Madagascar was carried out in collaboration with the Malagasy Institute pour la Conservation des Ecosyst{\`e}mes Tropicaux (MICET), and we are grateful to the Malagasy authorities for issuing research and export permits. Centro Jambatu researchers are indebted to Fundaci{\'o}n Otonga and the Ministerio de Ambiente of Ecuador who support amphibian research through the project “Conservation of Ecuadorian Amphibian Diversity and Sustainable Use of its Genetic Resources.” This work was supported by a Bauer Fellowship from Harvard University (L.A.O.), a National Science Foundation grant IOS-1557684 (L.A.O.), and a National Geographic Committee and Research and Exploration grant 9685-15 (L.A.O.). E.K.F. was supported by a National Science Foundation Postdoctoral Fellowship in Biology (DEB-1608997). L.A.O. conceived of the study, obtained funding, directed the research, and performed brain immunohistochemistry; L.A.C. and M.V. contributed to study design and edited the grants; A.B.R. E.K.F. and N.R. collected samples in Madagascar; E.K.F. E.E.T. and N.A.M. collected samples in Ecuador; N.A.M. performed alkaloid extractions; C.V. and S.A.T. performed mass spectrometry; A.B.R. performed microscopy and cell counting; E.K.F. sectioned brains, performed cell counting, and analyzed cell-count data; C.V. L.A.O. N.A.M. and E.K.F. analyzed alkaloid data; and E.K.F. and L.A.O. wrote the paper with contributions from all authors. The authors declare no competing interests. Funding Information: We would like to thank Mar{\'i}a Dolores Guarderas (Wikiri) for support in Ecuador, Joshua Nelson for help with R code, and Deborah Gordon, the members of the O{\textquoteright}Connell lab, and two anonymous reviewers for comments on the manuscript. We thank Roberto Marquez for producing the phylogeny in Figure 1 . Work in Madagascar was carried out in collaboration with the Malagasy Institute pour la Conservation des Ecosyst{\`e}mes Tropicaux (MICET), and we are grateful to the Malagasy authorities for issuing research and export permits. Centro Jambatu researchers are indebted to Fundaci{\'o}n Otonga and the Ministerio de Ambiente of Ecuador who support amphibian research through the project “Conservation of Ecuadorian Amphibian Diversity and Sustainable Use of its Genetic Resources.” This work was supported by a Bauer Fellowship from Harvard University (L.A.O.), a National Science Foundation grant IOS-1557684 (L.A.O.), and a National Geographic Committee and Research and Exploration grant 9685-15 (L.A.O.). E.K.F. was supported by a National Science Foundation Postdoctoral Fellowship in Biology ( DEB-1608997 ). Publisher Copyright: {\textcopyright} 2019 The Author(s)",
year = "2019",
month = dec,
day = "2",
doi = "10.1016/j.cub.2019.10.032",
language = "English (US)",
volume = "29",
pages = "4145--4151.e3",
journal = "Current Biology",
issn = "0960-9822",
publisher = "Cell Press",
number = "23",
}