RT Journal Article SR Electronic T1 Toxoplasma gondii infections are associated with boldness towards lions in wild hyena hosts JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.08.26.268805 DO 10.1101/2020.08.26.268805 A1 Eben Gering A1 Zachary M. Laubach A1 Patricia Weber A1 Gisela Soboll Hussey A1 Kenna D. S. Lehmann A1 Tracy M. Montgomery A1 Julie W. Turner A1 Wei Perng A1 Malit O. Pioon A1 Kay E. Holekamp A1 Thomas Getty YR 2020 UL http://biorxiv.org/content/early/2020/08/27/2020.08.26.268805.abstract AB Toxoplasma gondii is widely reported to manipulate the behavior of its non-definitive hosts in ways that promote lethal interactions with the parasite’s definitive feline hosts. Nonetheless, there is a lack of data on the association between T. gondii infection and costly behavioral interactions with felids in nature. Here, we report that three decades of field observations reveal T. gondii infected hyena cubs approach lions more closely than uninfected peers and have higher rates of lion mortality. Our findings support the hypothesis that T. gondii’s manipulation of host boldness is an extended phenotype that promotes parasite transmission from intermediate hosts to feline predators. While upregulating hyena boldness toward lions might achieve this, it may also reflect a collateral influence of manipulative traits that evolved in other hosts (e.g., rodents). In either case, our findings corroborate the potential impacts of a globally distributed and generalist parasite (T. gondii) on fitness-related interaction with felids in a wild host.One Sentence Summary Wild hyenas infected with the parasite T. gondii show evidence of costly behavioral manipulation when interacting with lions.Competing Interest StatementThe authors have declared no competing interest.