ArticleCurrent biology : CB2015
Evolutionary trade-off between vocal tract and testes dimensions in howler monkeys.
Article in Current biology : CB, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 35 papers, 1 of them a synthesis that pooled it.
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35 citing papers in PubMed, 1 synthesis or guideline pooled it, 151 citations in OpenAlex.
- Rethinking the frequency code: a meta-analytic review of the role of acoustic body size in communicative phenomena.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Pooled it
- The howler monkey genome provides new insights into the distinctive howling and folivorous adaptations of New World monkeys.Genome biology · 2026Article
- Phylogenomic analysis of vocal fold length evolution reveals links between vocal and auditory systems in terrestrial mammals.Molecular biology and evolution · 2026Article
- Behaviour and vocalization of Mongolian gazelle (Procapra gutturosa) in rutting harems considering the sex-specific vocal anatomy.Die Naturwissenschaften · 2026Article
- Learnt formant modulation via upper vocal tract movements in a marine mammal.Discover animals · 2026Article
- Rethinking Hominin Air Sac Loss in Light of Phylogenetically Meaningful Evidence.Evolutionary anthropology · 2025Article
- The domestication of the wolf larynx-testing the neural crest connection.Royal Society open science · 2025Article
- Nonlinear phenomena in mammalian vocal communication: an introduction and scoping review.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2025Article
- Mantled howler monkey males assess their rivals through formant spacing of long-distance calls.Primates; journal of primatology · 2024Article
- Twin vocal folds as a novel evolutionary adaptation for vocal communications in lemurs.Scientific reports · 2024Article
- Differences in sperm morphology between Alouatta palliata and Alouatta pigra are consistent with the intensity of sperm competition in each species.American journal of primatology · 2023Article
- Revisiting Nature's "Unifying Patterns": A Biological Appraisal.Biomimetics (Basel, Switzerland) · 2023Review
- Group size and mating system predict sex differences in vocal fundamental frequency in anthropoid primates.Nature communications · 2023Article
- Article
- Scent mark signal investment predicts fight dynamics in house mice.Proceedings. Biological sciences · 2023Article
- Vocal size exaggeration may have contributed to the origins of vocalic complexity.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2022Article
- Progress without exclusion in the search for an evolutionary basis of music.The Behavioral and brain sciences · 2021Article
- Selection on vocal output affects laryngeal morphology in rats.Journal of anatomy · 2021Article
- Selection on ultrasonic call rate in neonatal rats affects low frequency, but not ultrasonic, vocalizations in adults.Ethology : formerly Zeitschrift fur Tierpsychologie · 2020Article
- Floating frogs sound larger: environmental constraints on signal production drives call frequency changes.Die Naturwissenschaften · 2020Article
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9 authors at 7 institutions in 3 countries.
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Abstract
Males often face a trade-off between investments in precopulatory and postcopulatory traits [1], particularly when male-male contest competition determines access to mates [2]. To date, studies of precopulatory strategies have largely focused on visual ornaments (e.g., coloration) or weapon morphology (e.g., antlers, horns, and canines). However, vocalizations can also play an important role in both male competition and female choice [3-5]. We investigated variation in vocal tract dimensions among male howler monkeys (Alouatta spp.), which produce loud roars using a highly specialized and greatly enlarged hyoid bone and larynx [6]. We examined the relative male investment in hyoids and testes among howler monkey species in relation to the level of male-male competition and analyzed the acoustic consequences of variation in hyoid morphology. Species characterized by single-male groups have large hyoids and small testes, suggesting high levels of vocally mediated competition. Larger hyoids lower formant frequencies, probably increasing the acoustic impression of male body size and playing a role analogous to investment in large body size or weaponry. Across species, as the number of males per group increases, testes volume also increases, indicating higher levels of postcopulatory sperm competition, while hyoid volume decreases. These results provide the first evidence of an evolutionary trade-off between investment in precopulatory vocal characteristics and postcopulatory sperm production.
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