Duetting,or the stereotypical,repeated and often coordinated vocalizations between 2 individuals arose independently multiple times in the Order Primates.Across primate species,there exists substantial variation in te...Duetting,or the stereotypical,repeated and often coordinated vocalizations between 2 individuals arose independently multiple times in the Order Primates.Across primate species,there exists substantial variation in terms of timing,degree of overlap,and sex-specificity of duet contributions.There is increasing evidence that primates can modify the timing of their duet contributions relative to their partner,and this vocal flexibility may have been an important precursor to the evolution of human language.Here,we present the results of a fine-scale analysis of Gursky’s spectral tarsier Tarsius spectrumgurskyae duet phrases recorded in North Sulawesi,Indonesia.Specifically,we aimed to investigate individual-level variation in the female and male contributions to the duet,quantify individual-and pair-level differences in duet timing,and measure temporal precision of duetting individuals relative to their partner.We were able to classify female duet phrases to the correct individual with an 80%accuracy using support vector machines,whereas our classification accuracy for males was lower at 64%.Females were more variable than males in terms of timing between notes.All tarsier phrases exhibited some degree of overlap between callers,and tarsiers exhibited high temporal precision in their note output relative to their partners.We provide evidence that duetting tarsier individuals can modify their note output relative to their duetting partner,and these results support the idea that flexibility in vocal exchanges—a precursor to human language—evolved early in the primate lineage and long before the emergence of modern humans.展开更多
Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of ...Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of laboratory specimens during disturbance behavior. Vocal families had bony （not flexible or segmented） spines, well-developed anterior and/or posterior serrations, and statistically significantly longer spines. We compared morphology of the proximal end of the pectoral spine between vocal and silent species. For vocal taxa, microscopic rounded or bladed ridges or knobs were present on the dorsal process. Most silent species had reduced processes with exclusively smooth, convoluted, or honeycombed surfaces very similar to spine-locking surfaces, or they had novel surfaces （beaded, vacuolated, cobwebbed）. Most callichthyids had ridges but many were silent during disturbance. All doradid, most auchenipterid and most mochokid species were vocal and had ridges or knobs. Within the Auchenipteridae, vocal species had spines with greater weight and serration development but not length. Silent auchenipterids had thin, brittle, distally segmented spines with few microscopic serrations on only one margin and a highly reduced dorsal process lacking any known vocal morphology. Silent auchenipterids are derived and pelagic, while all vocal genera are basal and benthopelagic. This is the first phylogenetic evidence for stridulation mechanism loss within catfishes. Phylogenetic mapping of vocal ability, spine condition, and ecotype revealed the repeated presence of silence and vocal taxa, short and long spines, and ecotype shifts within clades. The appearance and loss of vocal behavior and supporting morphologies may have facilitated diversification among catfishes [Current Zoology 56 （1）： 73 89 2010].展开更多
基金Funding for this research was provided by a Fulbright ASEAN Research Award for U.S.Scholars(no award number given).
文摘Duetting,or the stereotypical,repeated and often coordinated vocalizations between 2 individuals arose independently multiple times in the Order Primates.Across primate species,there exists substantial variation in terms of timing,degree of overlap,and sex-specificity of duet contributions.There is increasing evidence that primates can modify the timing of their duet contributions relative to their partner,and this vocal flexibility may have been an important precursor to the evolution of human language.Here,we present the results of a fine-scale analysis of Gursky’s spectral tarsier Tarsius spectrumgurskyae duet phrases recorded in North Sulawesi,Indonesia.Specifically,we aimed to investigate individual-level variation in the female and male contributions to the duet,quantify individual-and pair-level differences in duet timing,and measure temporal precision of duetting individuals relative to their partner.We were able to classify female duet phrases to the correct individual with an 80%accuracy using support vector machines,whereas our classification accuracy for males was lower at 64%.Females were more variable than males in terms of timing between notes.All tarsier phrases exhibited some degree of overlap between callers,and tarsiers exhibited high temporal precision in their note output relative to their partners.We provide evidence that duetting tarsier individuals can modify their note output relative to their duetting partner,and these results support the idea that flexibility in vocal exchanges—a precursor to human language—evolved early in the primate lineage and long before the emergence of modern humans.
基金the Barbara-Sussman FundSigma-Xi+1 种基金SUNY-ESFsupported by MIMH training grant 5-T32-MH15793
文摘Stridulatory sound-producing behavior is widespread across catfish families, but some are silent. To understand why, we compared spine morphology and ecotype of silent and vocal clades. We determined vocal ability of laboratory specimens during disturbance behavior. Vocal families had bony （not flexible or segmented） spines, well-developed anterior and/or posterior serrations, and statistically significantly longer spines. We compared morphology of the proximal end of the pectoral spine between vocal and silent species. For vocal taxa, microscopic rounded or bladed ridges or knobs were present on the dorsal process. Most silent species had reduced processes with exclusively smooth, convoluted, or honeycombed surfaces very similar to spine-locking surfaces, or they had novel surfaces （beaded, vacuolated, cobwebbed）. Most callichthyids had ridges but many were silent during disturbance. All doradid, most auchenipterid and most mochokid species were vocal and had ridges or knobs. Within the Auchenipteridae, vocal species had spines with greater weight and serration development but not length. Silent auchenipterids had thin, brittle, distally segmented spines with few microscopic serrations on only one margin and a highly reduced dorsal process lacking any known vocal morphology. Silent auchenipterids are derived and pelagic, while all vocal genera are basal and benthopelagic. This is the first phylogenetic evidence for stridulation mechanism loss within catfishes. Phylogenetic mapping of vocal ability, spine condition, and ecotype revealed the repeated presence of silence and vocal taxa, short and long spines, and ecotype shifts within clades. The appearance and loss of vocal behavior and supporting morphologies may have facilitated diversification among catfishes [Current Zoology 56 （1）： 73 89 2010].
