{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:19:50Z","timestamp":1792790390057,"version":"4.5.0"},"posted":{"date-parts":[[2026,5,5]]},"group-title":"Animal Behavior and Cognition","reference-count":56,"publisher":"openRxiv","license":[{"start":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T00:00:00Z","timestamp":1777939200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nd\/4.0\/"}],"funder":[{"name":"National Institutes of Health","award":["R01AG071684"],"award-info":[{"award-number":["R01AG071684"]}]},{"name":"National Institutes of Health","award":["R01AG075914"],"award-info":[{"award-number":["R01AG075914"]}]},{"name":"National Institutes of Health","award":["R61AG078470"],"award-info":[{"award-number":["R61AG078470"]}]},{"name":"Natural Sciences and Engineering Research Council","award":["PGSD3 \u2013 577867 \u2013 2023"],"award-info":[{"award-number":["PGSD3 \u2013 577867 \u2013 2023"]}],"id":[{"id":"https:\/\/ror.org\/01h531d29","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2026,9,17]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  Many primates exhibit female philopatry and live in stable, female-bonded groups, where females are seldom exposed to novel same-sex conspecifics. Permanent group fusions are unique in bringing unfamiliar female conspecifics together but are rarely documented in these populations. We present a case study on a fusion of two groups from a hybrid population of baboons (\n                  <jats:italic>Papio cynocephalus<\/jats:italic>\n                  x\n                  <jats:italic>P. anubis<\/jats:italic>\n                  ) living in the Amboseli basin of Kenya. We compared the behavior of eight adult females after the fusion to the behavior of females in groups that had not fused and compared pre- and post-fusion fitness outcomes. Following the fusion, the group\u2019s activity budget and patterns of agonistic interactions were typical for the study population. Females preferred familiar grooming partners for a short period following the fusion; however, after three months, female grooming patterns were comparable to other groups, indicating rapid social integration. Females from the smaller pre-fusion group were lower ranking than females from the larger group. The fusion occurred following increased human-induced mortality in one of the two groups. From our limited sample, we observed no detectable fitness-related costs of fusion in terms of birth rates or offspring survival, while adult female mortality was low following the fusion. These results demonstrate the flexibility of female baboons in navigating exposure to novel same-sex conspecifics despite a species-typic pattern of female philopatry. Our results support previous research indicating that group fusions most likely occur when groups are too small to retain adult males, defend against predators, or compete with other groups.\n                <\/jats:p>","DOI":"10.64898\/2026.04.30.721977","type":"posted-content","created":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T11:40:20Z","timestamp":1777981220000},"source":"Crossref","is-referenced-by-count":0,"title":["Activity budgets, social behavior, and fitness outcomes associated with a group fusion in baboons (\n                  <i>Papio cynocephalus<\/i>\n                  x\n                  <i>P. anubis<\/i>\n                  )"],"prefix":"10.64898","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4894-6834","authenticated-orcid":false,"given":"Brian A.","family":"Lerch","sequence":"first","affiliation":[{"name":"Center for Population Biology, University of California Davis, Davis, CA, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1337-1946","authenticated-orcid":false,"given":"Maria J.A.","family":"Creighton","sequence":"additional","affiliation":[{"name":"Department of Biology, Duke University, Durham, NC, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. Kinyua","family":"Warutere","sequence":"additional","affiliation":[{"name":"Amboseli Baboon Research Project, Nairobi, Kenya"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0416-2958","authenticated-orcid":false,"given":"Jenny","family":"Tung","sequence":"additional","affiliation":[{"name":"Department of Biology, Duke University, Durham, NC, USA"},{"name":"Department of Evolutionary Anthropology, Duke University, Durham, NC, USA"},{"name":"Department of Primate Behavior and Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany"},{"name":"Canadian Institute for Advanced Research, Toronto, Canada"},{"name":"Faculty of Life Sciences, Institute of Biology, Leipzig University, Leipzig, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1187-0998","authenticated-orcid":false,"given":"Elizabeth A.","family":"Archie","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1313-488X","authenticated-orcid":false,"given":"Susan C.","family":"Alberts","sequence":"additional","affiliation":[{"name":"Department of Biology, Duke University, Durham, NC, USA"},{"name":"Department of Evolutionary Anthropology, Duke University, Durham, NC, USA"},{"name":"Duke University Population Research Institute, Duke University, Durham, NC, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026092211153080000_2026.04.30.721977v2.1","doi-asserted-by":"publisher","DOI":"10.1086\/285740"},{"key":"2026092211153080000_2026.04.30.721977v2.2","doi-asserted-by":"crossref","unstructured":"Alberts, S. 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