Books & Book chapters by Jordi Galbany
Dental wear in evolutionary and biocultural contexts, 2019
Galbany J, Twahirwa JC, Baiges-Sotos L, Kane EE, Tuyisingize D, Kaleme P, Rwetsiba A, Bitariho R,... more Galbany J, Twahirwa JC, Baiges-Sotos L, Kane EE, Tuyisingize D, Kaleme P, Rwetsiba A, Bitariho R, Cranfield MR, Bromage TG, Mudakikwa A, Stoinski TS, Robbins MM, McFarlin SC (2020) Dental macrowear in catarrhine primates: variability across species. In: Schmidt C & Watson JT (Eds.) Dental wear in evolutionary and biocultural contexts. Pp. 11-37. Elsevier/Academic Press.
Boletín de la Asociación Primatológica Española , 2017
Álvarez-Solas S & Galbany J (2017) Primatología Internacional: una visión de los avances de la pr... more Álvarez-Solas S & Galbany J (2017) Primatología Internacional: una visión de los avances de la primatología en todo el mundo. Boletín de la Asociación Primatológica Española 24(1): 110-117.
Boletín de la Asociación Primatológica Española, 2018
De Gibert N & Galbany J (2018) Cuarentena y transmisión de enfermedades infecciosas entre humanos... more De Gibert N & Galbany J (2018) Cuarentena y transmisión de enfermedades infecciosas entre humanos y chimpancés. Boletín de la Asociación Primatológica Española 25(1): 76-81.
Desde hace décadas los grandes simios han sido habituados a la presencia humana para poder realizar proyectos de investigación. En algunos proyectos incluso se ha incorporado el factor turismo, es decir ofrecer al visitante la experiencia de poder observar estos primates en libertad. Pero, ¿es nuestra presencia causante de alteraciones en su comportamiento o en su salud? ¿Con la habituación estamos afectando negativamente a los grandes simios?. Ilustraciones: Natàlia Sellés.
Boletín de la Asociación Primatológica Española, 2016
Galbany J (2016) Dardeo de primates salvajes: motivos y consecuencias. Boletín de la Asociación P... more Galbany J (2016) Dardeo de primates salvajes: motivos y consecuencias. Boletín de la Asociación Primatológica Española 23(1): 32-35.
Boletín de la Asociación Primatológica Española, 2015
Galbany J (2015) Investigación y conservación de los gorilas de montaña en Ruanda. Boletín de la ... more Galbany J (2015) Investigación y conservación de los gorilas de montaña en Ruanda. Boletín de la Asociación Primatológica Española 22(1): 8-17.
Homenaje al Dr. José Gibert Clols. Una vida dedicada a la ciencia y al conocimiento de los primeros europeos, 2016
Romero A, Galbany J & Pérez-Pérez A (2016) Ecología dental en primates y homininos fósiles. In: H... more Romero A, Galbany J & Pérez-Pérez A (2016) Ecología dental en primates y homininos fósiles. In: Homenaje al Dr. José Gibert Clols. Una vida dedicada a la ciencia y al conocimiento de los primeros europeos (Coordinador: Ribot Trafí F). Granada: Publicaciones Diputación de Granada. Pp. 163-175. ABSTRACT: La ecología dental es un enfoque clave para explicar cómo el diente responde al medioambiente en aspectos relacionados con la morfología y procesos de desgaste en la reconstrucción de las estrategias alimentarias en primates no-humanos y homininos fósiles desde una perspectiva evolutiva. Estudios morfométricos comparativos muestran como los dientes son estructuras óptimas para la masticación. Sin embargo, la forma y tamaño entre especies dependen en gran medida de limitaciones en el desarrollo, filogenia y ecología. En particular, la topografía oclusal varía en relación a la ecología alimentaria entre primates y refleja su adaptación para el procesamiento mecánico durante la alimentación. Dado que la funcionalidad óptima del diente puede variar con el desgaste, la interacción entre factores ecológicos y la pérdida de esmalte en primates no-humanos para inferir la dieta de especies extintas no se encuentra bien establecida. En este trabajo abordamos los problemas actuales en el estudio del desgaste dental a escala macro y microscópica relativos a las propiedades mecánicas de los alimentos y factores ecológicos. Nuestros estudios in vivo con primates cercopitécidos y poblaciones de cazadores-recolectores plantean nuevas preguntas y temas de discusión acerca de las propiedades físicas de los alimentos en el contexto del estudio sobre el desgaste dental. Palabras clave: Desgaste; diente; ecología alimentaria; primates.
Ni el propietario del copyright, ni los patrocinadores, ni las entidades que avalan esta obra, pu... more Ni el propietario del copyright, ni los patrocinadores, ni las entidades que avalan esta obra, pueden ser considerados legalmente responsables de la aparición de información inexacta, errónea o difamatoria, siendo los autores los responsables de la misma.
Papers by Jordi Galbany
Proceedings B, 2022
Mountain gorillas are particularly inbred compared to other gorillas and even the most inbred hum... more Mountain gorillas are particularly inbred compared to other gorillas and even the most inbred human populations. As mountain gorilla skeletal material accumulated during the 1970s, researchers noted their pronounced facial asymmetry and hypothesized that it reflects a population-wide chewing side preference. However, asymmetry has also been linked to environmental and genetic stress in experimental models. Here, we examine facial asymmetry in 114 crania from three Gorilla subspecies using 3D geometric morphometrics. We measure fluctuating asymmetry (FA), defined as random deviations from perfect symmetry, and population-specific patterns of directional asymmetry (DA). Mountain gorillas, with a current population size of about 1000 individuals, have the highest degree of facial FA (explaining 17% of total facial shape variation), followed by Grauer gorillas (9%) and western lowland gorillas (6%), despite the latter experiencing the greatest ecological and dietary variability. DA, while significant in all three taxa, explains relatively less shape variation than FA does. Facial asymmetry correlates neither with tooth wear asymmetry nor increases with age in a mountain gorilla subsample, undermining the hypothesis that facial asymmetry is driven by chewing side preference. An examination of temporal trends shows that stress-induced developmental instability has increased over the last 100 years in these endangered apes.
Scientific Reports, 2021
Acoustic signals that reliably indicate body size, which usually determines competitive ability, ... more Acoustic signals that reliably indicate body size, which usually determines competitive ability, are of particular interest for understanding how animals assess rivals and choose mates. Whereas body size tends to be negatively associated with formant dispersion in animal vocalizations, non-vocal signals have received little attention. Among the most emblematic sounds in the animal kingdom is the chest beat of gorillas, a non-vocal signal that is thought to be important in intra and inter-sexual competition, yet it is unclear whether it reliably indicates body size. We examined the relationship among body size (back breadth), peak frequency, and three temporal characteristics of the chest beat: duration, number of beats and beat rate from sound recordings of wild adult male mountain gorillas. Using linear mixed models, we found that larger males had significantly lower peak frequencies than smaller ones, but we found no consistent relationship between body size and the temporal characteristics measured. Taken together with earlier findings of positive correlations among male body size, dominance rank and reproductive success, we conclude that the gorilla chest beat is an honest signal of competitive ability. These results emphasize the potential of non-vocal signals to convey important information in mammal communication.
PLoS ONE, 2020
According to life history theory, natural selection has shaped trade-offs for allocating energy a... more According to life history theory, natural selection has shaped trade-offs for allocating energy among growth, reproduction and maintenance to maximize individual fitness. In social mammals body size and dominance rank are two key variables believed to influence female reproductive success. However, few studies have examined these variables together, particularly in long-lived species. Previous studies found that female dominance rank correlates with reproductive success in mountain gorillas (Gorilla beringei beringei), which is surprising given they have weak dominance relationships and experience seemingly low levels of feeding competition. It is not currently known whether this relationship is primarily driven by a positive correlation between rank and body size. We used the non-invasive parallel laser method to measure two body size variables (back breadth and body length) of 34 wild adult female mountain gorillas, together with long-term dominance and demography data to investigate the interrelationships among body size, dominance rank and two measures of female reproductive success (inter-birth interval N = 29 and infant mortality N = 64). Using linear mixed models, we found no support for body size to be significantly correlated with dominance rank or female reproductive success. Higher-ranking females had significantly shorter inter-birth intervals than lower-ranking ones, but dominance rank was not significantly correlated with infant mortality. Our results suggest that female dominance rank is primarily determined by factors other than linear body dimensions and that high rank provides benefits even in species with weak dominance relationships and abundant year-round food resources. Future studies should focus on the mechanisms behind heterogeneity in female body size in relation to trade-offs in allocating energy to growth, maintenance and lifetime reproductive success.
Journal of Human Evolution, 2020
Martínez LM, Estebaranz-Sánchez F, Ferràndez-Cañadell C, Romero A, Ribot F, Galbany J, Gibert L &... more Martínez LM, Estebaranz-Sánchez F, Ferràndez-Cañadell C, Romero A, Ribot F, Galbany J, Gibert L & Pérez-Pérez A (2020) Buccal dental-microwear and feeding ecology of Early Pleistocene Theropithecus oswaldi from Cueva Victoria (Spain). Journal of Human Evolution 142: 102736 (12p.). ABSTRACT: Despite the scarcity of fossil specimens of Theropithecus oswaldi in Eurasia, its presence out of Africa attests to the great dispersal of this Papionini genus during the Early Pleistocene. In the present study, we analyze the buccal dental microwear of T. oswaldi (T. o. leakeyi) fossil specimens from Cueva Victoria (Southeastern Spain). This analysis is the first characterization of the feeding ecology of T. oswaldi in Europe. The buccal microwear pattern of the molar and premolar teeth of T. oswaldi from Cueva Victoria shows great similarities to that observed for the extant frugivorous forest-dwelling Mandrillus sphinx and mangabeys (Cercocebus sp.)—both species adapted to durophagous dietary habits—while significantly different from that observed for the gramnivorous Theropithecus gelada. These results suggest that T. oswaldi from Cueva Victoria could have exploited both hard-shelled fruits or seeds and succulent fruits from open and forested Mediterranean ecosystems.
Animal Behaviour, 2019
Wright E, Galbany J, McFarlin SC, Ndayishimiye E, Stoinski TS & Robbins MM (2019) Male body size,... more Wright E, Galbany J, McFarlin SC, Ndayishimiye E, Stoinski TS & Robbins MM (2019) Male body size, dominance rank and strategic use of aggression in a group-living mammal. Animal Behaviour 151:87-102.
ABSTRACT: Body size is a key determinant of male fighting ability and reproductive success in many animal species, but relationships between these variables have only rarely been examined in group-living animals in which body size often correlates with dominance rank. We examined the relationships between body size (crest height, back breadth and body length), dominance rank, alpha male tenure length, number of adult females and patterns of aggression in 26 wild adult male mountain gorillas, Gorilla beringei beringei, living in multimale groups. A composite measure combining crest height and back breadth (variables were highly correlated and combined into a cresteback score), but not body length, significantly correlated with dominance rank, alpha male tenure length and number of adult females per group. The alpha male had the largest cresteback score in six of the seven groups, and in the majority of dyads the male with the higher cresteback score was higher ranking. The frequency (and intensity on mating days) of aggressive contests was higher between males close in rank. Additionally, aggression occurred more frequently when the initiator was larger than the recipient. Our results suggest that factors other than body size are likely to influence dominance rank, but large size helps males attain and retain high dominance rank, probably leading to greater reproductive success. Further studies on how the timing and intensity of maleemale competition influences life history trade-offs between investment in secondary sexual characteristics, body condition and survival may explain variance in lifetime reproductive success within and between species.
Keywords: aggression, alpha male tenure length, body size, dominance rank, Gorilla beringei beringei, number of females, sexual selection
Journal of Morphology, 2018
Nova Delgado M, Pérez-Pérez A & Galbany J (2019) Morphological variation and covariation in mandi... more Nova Delgado M, Pérez-Pérez A & Galbany J (2019) Morphological variation and covariation in mandibular molars of platyrrhine primates. Journal of Morphology 280:20-34.
American Journal of Physical Antrhropology, 2018
Objectives: Ecological factors, but also tooth-to-tooth contact over time, have a dramatic effect... more Objectives: Ecological factors, but also tooth-to-tooth contact over time, have a dramatic effect on tooth wear in primates. The aim of this study is to test whether incisor tooth wear changes predictably with age, and can thus be used as an age estimation method in a wild population of mountain gorillas (Gorilla beringei beringei) from Volcanoes National Park, Rwanda. Methods: In mountain gorillas of confidently-known chronological age (N=24), we measured the crown height of all permanent maxillary and mandibular incisors (I1, I1, I2, I2) as a proxy for incisal macrowear. Linear and quadratic regressions for each incisor were used to test whether age can be predicted by crown height. Using these models, we then predicted age at death of two individual mountain gorillas of probable identifications, based on their incisor crown height. Results: Age decreased significantly with incisor height for all teeth, but the upper first incisors (I1) provided the best results, with lowest Akaike’s Information Criterion corrected for small sample size (AICc) and lowest Standard Error of the Estimate (SEE). When the best age equations for each sex were applied to gorillas with probable identifications, the predicted ages differed 1.58 and 3.33 years from the probable ages of these individuals. Conclusions: Our findings corroborate that incisor crown height, a proxy for incisal wear, varies predictably with age. This relationship can be used to estimate age at death of unknown gorillas in the skeletal collection, and in some cases, to corroborate the identity of individual gorillas recovered from the forest postmortem at an advanced state of decomposition. Such identifications help fill gaps in the demographic database, and support research that requires individual-level data.
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Books & Book chapters by Jordi Galbany
Desde hace décadas los grandes simios han sido habituados a la presencia humana para poder realizar proyectos de investigación. En algunos proyectos incluso se ha incorporado el factor turismo, es decir ofrecer al visitante la experiencia de poder observar estos primates en libertad. Pero, ¿es nuestra presencia causante de alteraciones en su comportamiento o en su salud? ¿Con la habituación estamos afectando negativamente a los grandes simios?. Ilustraciones: Natàlia Sellés.
Papers by Jordi Galbany
ABSTRACT: Body size is a key determinant of male fighting ability and reproductive success in many animal species, but relationships between these variables have only rarely been examined in group-living animals in which body size often correlates with dominance rank. We examined the relationships between body size (crest height, back breadth and body length), dominance rank, alpha male tenure length, number of adult females and patterns of aggression in 26 wild adult male mountain gorillas, Gorilla beringei beringei, living in multimale groups. A composite measure combining crest height and back breadth (variables were highly correlated and combined into a cresteback score), but not body length, significantly correlated with dominance rank, alpha male tenure length and number of adult females per group. The alpha male had the largest cresteback score in six of the seven groups, and in the majority of dyads the male with the higher cresteback score was higher ranking. The frequency (and intensity on mating days) of aggressive contests was higher between males close in rank. Additionally, aggression occurred more frequently when the initiator was larger than the recipient. Our results suggest that factors other than body size are likely to influence dominance rank, but large size helps males attain and retain high dominance rank, probably leading to greater reproductive success. Further studies on how the timing and intensity of maleemale competition influences life history trade-offs between investment in secondary sexual characteristics, body condition and survival may explain variance in lifetime reproductive success within and between species.
Keywords: aggression, alpha male tenure length, body size, dominance rank, Gorilla beringei beringei, number of females, sexual selection
Desde hace décadas los grandes simios han sido habituados a la presencia humana para poder realizar proyectos de investigación. En algunos proyectos incluso se ha incorporado el factor turismo, es decir ofrecer al visitante la experiencia de poder observar estos primates en libertad. Pero, ¿es nuestra presencia causante de alteraciones en su comportamiento o en su salud? ¿Con la habituación estamos afectando negativamente a los grandes simios?. Ilustraciones: Natàlia Sellés.
ABSTRACT: Body size is a key determinant of male fighting ability and reproductive success in many animal species, but relationships between these variables have only rarely been examined in group-living animals in which body size often correlates with dominance rank. We examined the relationships between body size (crest height, back breadth and body length), dominance rank, alpha male tenure length, number of adult females and patterns of aggression in 26 wild adult male mountain gorillas, Gorilla beringei beringei, living in multimale groups. A composite measure combining crest height and back breadth (variables were highly correlated and combined into a cresteback score), but not body length, significantly correlated with dominance rank, alpha male tenure length and number of adult females per group. The alpha male had the largest cresteback score in six of the seven groups, and in the majority of dyads the male with the higher cresteback score was higher ranking. The frequency (and intensity on mating days) of aggressive contests was higher between males close in rank. Additionally, aggression occurred more frequently when the initiator was larger than the recipient. Our results suggest that factors other than body size are likely to influence dominance rank, but large size helps males attain and retain high dominance rank, probably leading to greater reproductive success. Further studies on how the timing and intensity of maleemale competition influences life history trade-offs between investment in secondary sexual characteristics, body condition and survival may explain variance in lifetime reproductive success within and between species.
Keywords: aggression, alpha male tenure length, body size, dominance rank, Gorilla beringei beringei, number of females, sexual selection
Abstract
There is much debate on the dietary adaptations of the robust hominin lineages during the Pliocene-Pleistocene transition. It has been argued that the shift from C3 to C4 ecosystems in Africa was the main factor responsible for the robust dental and facial anatomical adaptations of Paranthropus taxa, which might be indicative of the consumption of fibrous, abrasive plant foods in open environments. However, occlusal dental microwear data fail to provide evidence of such dietary adaptations and are not consistent with isotopic evidence that supports greater C4 food intake for the robust clades than for the gracile australopithecines. We provide evidence from buccal dental microwear data that supports softer dietary habits than expected for P. aethiopicus and P. boisei based both on masticatory apomorphies and isotopic analyses. On one hand, striation densities on the buccal enamel surfaces of paranthropines teeth are low, resembling those of H. habilis and clearly differing from those observed on H. ergaster, which display higher scratch densities indicative of the consumption of a wide assortment of highly abrasive foodstuffs. Buccal dental microwear patterns are consistent with those previously described for occlusal enamel surfaces, suggesting that Paranthropus consumed much softer diets than previously presumed and thus calling into question a strict interpretation of isotopic evidence. On the other hand, the significantly high buccal scratch densities observed in the H. ergaster specimens are not consistent with a highly specialized, mostly carnivorous diet; instead, they support the consumption of a wide range of highly abrasive food items.
diet are related to tooth wear in wild mountain gorillas (Gorilla beringei beringei) from Volcanoes National Park, Rwanda.
Material and Methods: We calculated the percent of dentine exposure (PDE) for all permanent molars (M1–M3) of known-age mountain gorillas (N523), to test whether PDE varied with age using regression analysis. For each molar position, we also performed stepwise multiple linear regression to test the effects of age and percentage of time spent feeding on different food categories on PDE, for individuals subject to long-term observational studies by the Dian Fossey Gorilla Fund International’s Karisoke Research Center.
Results: PDE increased significantly with age for both sexes in all molars. Moreover, a significant effect of gritty plant root consumption on PDE was found among individuals. Our results support prior reports indicating reduced tooth wear in mountain gorillas compared to western gorillas, and compared to other known-aged samples of primate taxa from forest and savanna habitats.
Discussion: Our findings corroborate that mountain gorillas present very low molar wear, and support the hypothesis that age and the consumption of particular food types, namely roots, are significant determinants of tooth wear variation in mountain gorillas. Future research should characterize the mineral composition of the soil in the Virunga habitat, to test the hypothesis that the physical and abrasive properties of gritty foods such as roots influence intra and interspecific patterns of tooth wear.