Thomas Geissmann
Biographic Data
| ID | 627775 |
|---|---|
| NAME | Thomas Geissmann |
| GIVEN NAMES | Thomas |
| FAMILY NAME | Geissmann |
| SIGNATURE | GEISSMANN T |
| AFFILIATIONS | University of Zurich |
| ORCID | 0000-0003-4577-5937 |
| VERIFIED | Yes |
| TOTAL WORKS | 29 |
| TOTAL CITATIONS | 111 |
| WORKS AS AUTHOR | 29 |
| WORKS AS EDITOR | 0 |
| FIRST PUBLICATION YEAR | 1983 |
| LATEST PUBLICATION YEAR | 2023 |
| H-INDEX | 5 |
A cooperation experiment with white-handed gibbons (Hylobates lar)
Cooperative behaviors among individuals of numerous species play a crucial role in social interactions. There is a special interest in investigating the occurrence of cooperation among apes because this knowledge could also shed light on evolutionary processes and help us understand the origin and development of cooperation in humans and primates in general. Gibbons are phylogenetically intermediate between the great apes and monkeys, and therefo…
Individuality in male songs of wild black crested Gibbons ( Nomascus concolor )
This is the first study of vocal individuality in male songs of black crested gibbons. The sound recordings were carried out at two field sites, Pinghe, Ailao Mountains, and Dazhaizi, Wuliang Mountains, both located in Yunnan province, China. A total of 127 coda phrases of 38 male songs bouts of eight individual male gibbons were analyzed. Stepwise discriminant function analysis was used to examine the acoustic individuality of the males. We foun…
A new species of snub‐nosed monkey, genus Rhinopithecus Milne‐Edwards, 1872 (Primates, Colobinae), from northern Kachin state, northeastern Myanmar
We describe a snub‐nosed monkey that is new to science from the high altitudes of northeastern Kachin state, northeastern Myanmar, the Burmese snub‐nosed monkey, Rhinopithecus strykeri sp. nov. Descriptions are based on a skin and skulls of four specimens obtained from local hunters. The new species is geographically isolated from other snub‐nosed monkeys and separated from them by two major barriers—the Mekong and the Salween (Thanlwin) rivers. …
Are Hylobates lar Extirpated from China
The Nangunhe Nature Reserve in Southwest Yunnan (PRC) has long been presumed to be the last stronghold of lar (or white-handed) gibbons (Hylobates lar) in China and the likely last place of occurrence of Hylobates lar yunnanensis. We conducted a comprehensive survey to assess the status of lar gibbons at Nangunhe. We found no visual or auditory evidence of them still residing at the reserve and therefore tentatively conclude that lar gibbons have…
Call diversity of wild male orangutans
Over the past 20 years several studies have attempted to clarify orangutan systematics based on DNA sequences and karyological and morphological data; however, the systematic and phylogenetic relationships among orangutan taxa remain controversial. Surprisingly, few systematic studies have used data from wild‐living orangutans of exactly known provenance. Furthermore, most of these studies pooled data from huge geographic areas in their analyses,…
Radiographic evaluation of neonatal skeletal development in Callimico goeldii reveals closer similarity to Callithrix jacchus than to Saguinus oedipus
The phylogenetic affinities of the neotropical Goeldi's monkey ( Callimico goeldii ) have long been a matter of debate. Whereas most morphological evidence appears to place Callimico in a sister group position relative to the Callitrichidae, genetic studies place C. goeldii within the Callitrichidae and suggest that it is more closely related to marmosets than to tamarins. The present study presents the first radiographic analysis comparing the s…
Diurnal distribution of loud calls in sympatric wild indris (Indri indri) and ruffed lemurs (Varecia variegata)
Calling in wild silvery gibbons (Hylobates moloch) in Java (Indonesia)
Hardly any behavioral data are available for the silvery gibbon (Hylobates moloch), an endangered primate that is endemic to the island of Java, Indonesia. We studied the singing behavior of the easternmost population of this species in the Dieng mountains, central Java, in 1998-1999. We aimed to document the timing of singing, quantify the amount of singing by the respective sexes, and explore the role of bioacoustics in density estimation. A to…
Vocal Diversity and Taxonomy of Nomascus in Cambodia
New species of woolly lemurAvahi (primates
There are at least three distinct taxa of woolly lemurs (genus Avahi) in western Madagascar. The range of Avahi occidentalis extends north and east of the Betsiboka River to the Bay of Narinda. Avahi unicolor occurs well to the north, including the Ampasindava peninsula and the Manongarivo Special Reserve. Here we describe a third Avahi population in central western Madagascar, which was discovered in the Bemaraha Strict Nature Reserve in the Tsi…
Asian Primate Classification
Taxonomy and evolution of gibbons
Because the fossil history of gib-bons is virtually unknown,1,2 gibbon evolution can only be reconstructed from a comparative analysis of evolu-tionarily informative characteristics of modern gibbons and, to some de-gree, of related primate taxa that can be used as outgroups. Several studies have tried to recon-struct gibbon phylogeny, using fur coloration, morphological, vocal, or molecular data.3–10 Each study pro-duced a different result. As a…
Circumfacial Markings in Siamang and Evolution of the Face Ring in the Hylobatidae
Duet‐splitting and the evolution of gibbon songs
Unlike the great apes and most other primates, all species of gibbons are known to produce elaborate, species‐specific and sex‐specific patterns of vocalisation usually referred to as ‘'songs”. In most, but not all, species, mated pairs may characteristically combine their songs in a relatively rigid pattern to produce coordinated duet songs. Previous studies disagree on whether duetting or the absence of duetting represented the primitive condit…
Distribution and Geographic Variation in the Western Woolly Lemur (Avahi occidentalis) with Description of a New Species (A. unicolor
The yellow-cheeked gibbon (Hylobates gabriellae) in nam bai cat tien (southern vietnam) revisited
Behavioural development of twin siamangs (Hylobates syndactylus)
A primate survey in northern Bolivia, with special reference to Goeldi’s monkey,Callimico goeldii
The indris of Anjanaharibe-Sud, northeastern Madagascar
Sympatry between white-handed gibbons (Hylobates lar) and pileated gibbons (H. pileatus) in Southeastern Thailand
Group harmony in gibbons
Forthcoming in American Journal of Primatology
Twinning frequency in catarrhine primates
A female black gibbon,Hylobates concolor subspecies, from Northeastern Vietnam
Genetic polymorphisms in three Alpine populations (Visp valleys, Switerland)
Phenotype distributions and allele frequencies of 13 blood proteins are presented for the populations of the three Visp valleys, situated in the Swiss Alps. Blood samples of a total of 883 individuals were electrophoretically analysed. The three populations were statistically compared with each other, and with an additional sample from the literature thought to be representative of the entire Swiss population. Statistical differences are revealed…
Asian Primate Classification
The indris of Anjanaharibe-Sud, northeastern Madagascar
Vocal Diversity and Taxonomy of Nomascus in Cambodia
A primate survey in northern Bolivia, with special reference to Goeldi’s monkey,Callimico goeldii
Length estimate for KNM-ER 736, a hominid femur from the lower pleistocene of East Africa
Are Hylobates lar Extirpated from China
The Nangunhe Nature Reserve in Southwest Yunnan (PRC) has long been presumed to be the last stronghold of lar (or white-handed) gibbons (Hylobates lar) in China and the likely last place of occurrence of Hylobates lar yunnanensis. We conducted a comprehensive survey to assess the status of lar gibbons at Nangunhe. We found no visual or auditory evidence of them still residing at the reserve and therefore tentatively conclude that lar gibbons have…
A female black gibbon,Hylobates concolor subspecies, from Northeastern Vietnam
Circumfacial Markings in Siamang and Evolution of the Face Ring in the Hylobatidae
Twinning frequency in catarrhine primates
A sternal gland in the Siamang Gibbon(Hylobates syndactylus)
Female capped gibbon (Hylobates pileatus Gray 1891) sings male song
Female capped gibbon (Hylobates pileatus Gray 1891) sings male song
Length estimate for KNM-ER 736, a hominid femur from the lower pleistocene of East Africa
Genetic polymorphisms in three Alpine populations (Visp valleys, Switerland)
Phenotype distributions and allele frequencies of 13 blood proteins are presented for the populations of the three Visp valleys, situated in the Swiss Alps. Blood samples of a total of 883 individuals were electrophoretically analysed. The three populations were statistically compared with each other, and with an additional sample from the literature thought to be representative of the entire Swiss population. Statistical differences are revealed…
Twinning frequency in catarrhine primates
A sternal gland in the Siamang Gibbon(Hylobates syndactylus)
A female black gibbon,Hylobates concolor subspecies, from Northeastern Vietnam
Group harmony in gibbons
Forthcoming in American Journal of Primatology
Twinning frequency in catarrhine primates
Sympatry between white-handed gibbons (Hylobates lar) and pileated gibbons (H. pileatus) in Southeastern Thailand
The indris of Anjanaharibe-Sud, northeastern Madagascar
Behavioural development of twin siamangs (Hylobates syndactylus)
A primate survey in northern Bolivia, with special reference to Goeldi’s monkey,Callimico goeldii
The yellow-cheeked gibbon (Hylobates gabriellae) in nam bai cat tien (southern vietnam) revisited
Distribution and Geographic Variation in the Western Woolly Lemur (Avahi occidentalis) with Description of a New Species (A. unicolor
Duet‐splitting and the evolution of gibbon songs
Unlike the great apes and most other primates, all species of gibbons are known to produce elaborate, species‐specific and sex‐specific patterns of vocalisation usually referred to as ‘'songs”. In most, but not all, species, mated pairs may characteristically combine their songs in a relatively rigid pattern to produce coordinated duet songs. Previous studies disagree on whether duetting or the absence of duetting represented the primitive condit…
Taxonomy and evolution of gibbons
Because the fossil history of gib-bons is virtually unknown,1,2 gibbon evolution can only be reconstructed from a comparative analysis of evolu-tionarily informative characteristics of modern gibbons and, to some de-gree, of related primate taxa that can be used as outgroups. Several studies have tried to recon-struct gibbon phylogeny, using fur coloration, morphological, vocal, or molecular data.3–10 Each study pro-duced a different result. As a…
Circumfacial Markings in Siamang and Evolution of the Face Ring in the Hylobatidae
Asian Primate Classification
New species of woolly lemurAvahi (primates
There are at least three distinct taxa of woolly lemurs (genus Avahi) in western Madagascar. The range of Avahi occidentalis extends north and east of the Betsiboka River to the Bay of Narinda. Avahi unicolor occurs well to the north, including the Ampasindava peninsula and the Manongarivo Special Reserve. Here we describe a third Avahi population in central western Madagascar, which was discovered in the Bemaraha Strict Nature Reserve in the Tsi…
Diurnal distribution of loud calls in sympatric wild indris (Indri indri) and ruffed lemurs (Varecia variegata)
Calling in wild silvery gibbons (Hylobates moloch) in Java (Indonesia)
Hardly any behavioral data are available for the silvery gibbon (Hylobates moloch), an endangered primate that is endemic to the island of Java, Indonesia. We studied the singing behavior of the easternmost population of this species in the Dieng mountains, central Java, in 1998-1999. We aimed to document the timing of singing, quantify the amount of singing by the respective sexes, and explore the role of bioacoustics in density estimation. A to…
Vocal Diversity and Taxonomy of Nomascus in Cambodia
Call diversity of wild male orangutans
Over the past 20 years several studies have attempted to clarify orangutan systematics based on DNA sequences and karyological and morphological data; however, the systematic and phylogenetic relationships among orangutan taxa remain controversial. Surprisingly, few systematic studies have used data from wild‐living orangutans of exactly known provenance. Furthermore, most of these studies pooled data from huge geographic areas in their analyses,…
Radiographic evaluation of neonatal skeletal development in Callimico goeldii reveals closer similarity to Callithrix jacchus than to Saguinus oedipus
The phylogenetic affinities of the neotropical Goeldi's monkey ( Callimico goeldii ) have long been a matter of debate. Whereas most morphological evidence appears to place Callimico in a sister group position relative to the Callitrichidae, genetic studies place C. goeldii within the Callitrichidae and suggest that it is more closely related to marmosets than to tamarins. The present study presents the first radiographic analysis comparing the s…
Biology (28 works) · Zoology (22 works) · Animal Vocal Communication and Behavior (16 works) · Primate Behavior and Ecology (16 works) · Animal ecology (15 works) · Geography (14 works) · Animal Behavior and Reproduction (13 works) · Ecology (13 works) · Hylobates (11 works) · Demography (7 works)