1. Functional traits and functional diversity measures are increasingly being used to examine lan... more 1. Functional traits and functional diversity measures are increasingly being used to examine land use effects on biodiversity and community assembly rules. 2. Morphological traits are frequently derived from a mean value of many individuals, and used directly as functional traits. However, this approach overlooks the importance of intraspecific differences. 3. We collected morphometric data from over 1700 individuals of 12 species of dung beetle to establish whether morphological measurements can be used as predictors of behavioral traits. We also compared morphology among individuals collected from different land uses to identify if intra-specific differences in morphology vary among land use types. 4. We show that leg and eye measurements can be used to predict dung beetle nesting behavior and period of activity, and used this information to confirm the previously unresolved nesting behavior for Synapsis ritsemae. 5. We found intra-specific differences in morphological traits across different land use types. Phenotypic plasticity was found for traits associated with dispersal (wing aspect ratio and wing loading) and reproductive capacity (abdomen size). 6. The ability to predict behavioral functional traits from morphology is useful where the behavior of dung beetles cannot be directly observed, especially in tropical environments where the ecology of many species is poorly understood. 7. There have been very few studies investigating variability in animal traits. We provide evidence that land use change can cause phenotypic plasticity in tropical dung beetle species. Our results reinforce recent calls for intraspecific variation in traits to receive more attention within community ecology
Dung beetles fulfill several key functions in ecosystems but their role as secondary seed dispers... more Dung beetles fulfill several key functions in ecosystems but their role as secondary seed dispersers is probably one of the most complex ones. Various factors, such as seed characteristics, dispersal pattern induced by the primary disperser, season, and habitat, can affect the seed–beetle interaction. Particularly little is known about the fate of seeds primarily dispersed in small feces. The aim of this study was to investigate the effects of these factors on the dung beetle community (species composition, number and size of individuals) and its consequences on burial occurrence and depth of seeds primarily dispersed by two tamarin species. We captured dung beetles in a Peruvian rain forest with 299 dung-baited pitfall traps to characterize the dung beetle community. Seed burial occurrence and depth were assessed by marking in situ 551 dispersed seeds in feces placed in cages. Among these seeds, 22.5 percent were buried by dung beetles after 2 d. We observed a significant effect of the amount of dung, season, time of deposition, and habitat on the number of individuals and species of dung beetles, as well as on seed burial occurrence and depth, while the tamarin species significantly influenced only the number and the size of dung beetles. This seed dispersal loop is particularly important for forest regeneration: small to large seeds dispersed by tamarins in secondary forest can be buried by dung beetles. These seeds can thus benefit from a better protection against predation and a more suitable microenvironment for germination, potentially enhancing seedling recruitment.Los coleópteros coprófagos desempeñan diversas funciones en los ecosistemas, siendo probablemente su papel como dispersores secundarios de semillas uno de los más complejos debido a que diversos factores como características de las semillas, patrón de defecación del dispersor primario, hábitat y estación pueden afectar de muchas maneras la interacción semilla-coleóptero. Poco se conoce sobre el destino de las semillas dispersadas en heces pequeñas. El objetivo de este estudio fue determinar los efectos de estos factores sobre la comunidad de coleópteros (composición de especies, número y tamaño de individuos) y sus consecuencias sobre la ocurrencia de entierro y su profundidad para semillas dispersadas por dos especies de “pichicos”. En un bosque tropical húmedo peruano se colectaron coleópteros con 299 trampas de caída cebadas con heces para caracterizar la comunidad de coleópteros. Se marcaron in situ y se protegieron con malla 551 semillas dispersadas en las heces para evaluar la ocurrencia de semillas enterradas y la profundidad de entierro. De las semillas marcadas, 22.5 por ciento fueron enterradas por coleópteros después de dos días. Se observó un efecto significativo de la cantidad de materia fecal, estación, hora de defecación y hábitat sobre el número de individuos y especies de coleópteros, así como también en la ocurrencia y profundidad de entierro de las semillas. La especie de “pichico” solo influyó en el número y el tamaño de los coleópteros coprófagos. Este ciclo de dispersión de semillas es particularmente importante para la regeneración del bosque: semillas de diferentes tamaños dispersadas por los “pichicos” en el bosque secundario pueden ser enterradas por los coleópteros coprófagos. Esas semillas obtienen una mejor protección contra los predadores y un microambiente más apropiado para la germinación, aumentando potencialmente el reclutamiento de las plántulas.
Intensification of framing practices after the Second World War has led to wide scale loss of sem... more Intensification of framing practices after the Second World War has led to wide scale loss of semi-natural grasslands throughout the UK. Flood-plain meadows (NVC MG4 Alopecurus pratensis–Sanguisorba officinalis grassland) suffered under these changes in agricultural management, and now cover an area of <1500 ha in England and Wales. In 1985, an experiment was initiated at Somerford Mead, Oxford, with the target of re-creating MG4 grassland. The grassland was established with a sown seed mixture harvested from local MG4 grassland. A replicated block experiment was set up to look at the effects of sheep, cattle and no grazing on the establishment of the target floral community. In 2002, the effects of these management regimes on beetle communities were investigated. Grazing regime was seen to be the primary determinant of abundance, species richness and species assemblage of the beetle population. Vegetation structure was also found to influence beetle diversity. The percentage cover of the legume Trifolium repens had important effects on beetle community assemblage, whilst Trifolium pratense was strongly correlated with the abundance of three common phytophagous beetles. This study provides a preliminary investigation into the responses of beetle communities to management intended for the re-creation of the plant communities of this threatened grassland habitat.
Skip to Main Content. Wiley Online Library will be disrupted on 7 July from 10:00-12:00 BST (05:0... more Skip to Main Content. Wiley Online Library will be disrupted on 7 July from 10:00-12:00 BST (05:00-07:00 EDT) for essential maintenance. ...
The morphology of the labrum (epipharynx, ikrioma and aboral surface) of adult Aphodiini is figur... more The morphology of the labrum (epipharynx, ikrioma and aboral surface) of adult Aphodiini is figured and discussed. An updated glossary of the constitutive parts is presented.
A key challenge for tropical conservation biologists is to assess how forest management practices... more A key challenge for tropical conservation biologists is to assess how forest management practices affect biodiversity and associated ecosystem functions. Dung beetles (Scarabaeidae: Scarabaeinae) provide an ideal focal guild for such studies. We compared dung beetle assemblages and experimentally assessed rates of dung removal and seed burial in undisturbed forest, low-intensity selectively logged forest under sustainable forest management, and high-intensity logged forest, not under sustainable management in ...
Natural sciences conservation group newsletter, Jan 1, 2000
Close Document Image Close Document Printer Image Print This Document! Conservation Information N... more Close Document Image Close Document Printer Image Print This Document! Conservation Information Network (BCIN). Author: Mann, Darren J. Title Article/Chapter: &quot;Pests from non-collection sources&quot; Title of Source: Natural ...
1. Functional traits and functional diversity measures are increasingly being used to examine lan... more 1. Functional traits and functional diversity measures are increasingly being used to examine land use effects on biodiversity and community assembly rules. 2. Morphological traits are frequently derived from a mean value of many individuals, and used directly as functional traits. However, this approach overlooks the importance of intraspecific differences. 3. We collected morphometric data from over 1700 individuals of 12 species of dung beetle to establish whether morphological measurements can be used as predictors of behavioral traits. We also compared morphology among individuals collected from different land uses to identify if intra-specific differences in morphology vary among land use types. 4. We show that leg and eye measurements can be used to predict dung beetle nesting behavior and period of activity, and used this information to confirm the previously unresolved nesting behavior for Synapsis ritsemae. 5. We found intra-specific differences in morphological traits across different land use types. Phenotypic plasticity was found for traits associated with dispersal (wing aspect ratio and wing loading) and reproductive capacity (abdomen size). 6. The ability to predict behavioral functional traits from morphology is useful where the behavior of dung beetles cannot be directly observed, especially in tropical environments where the ecology of many species is poorly understood. 7. There have been very few studies investigating variability in animal traits. We provide evidence that land use change can cause phenotypic plasticity in tropical dung beetle species. Our results reinforce recent calls for intraspecific variation in traits to receive more attention within community ecology
Dung beetles fulfill several key functions in ecosystems but their role as secondary seed dispers... more Dung beetles fulfill several key functions in ecosystems but their role as secondary seed dispersers is probably one of the most complex ones. Various factors, such as seed characteristics, dispersal pattern induced by the primary disperser, season, and habitat, can affect the seed–beetle interaction. Particularly little is known about the fate of seeds primarily dispersed in small feces. The aim of this study was to investigate the effects of these factors on the dung beetle community (species composition, number and size of individuals) and its consequences on burial occurrence and depth of seeds primarily dispersed by two tamarin species. We captured dung beetles in a Peruvian rain forest with 299 dung-baited pitfall traps to characterize the dung beetle community. Seed burial occurrence and depth were assessed by marking in situ 551 dispersed seeds in feces placed in cages. Among these seeds, 22.5 percent were buried by dung beetles after 2 d. We observed a significant effect of the amount of dung, season, time of deposition, and habitat on the number of individuals and species of dung beetles, as well as on seed burial occurrence and depth, while the tamarin species significantly influenced only the number and the size of dung beetles. This seed dispersal loop is particularly important for forest regeneration: small to large seeds dispersed by tamarins in secondary forest can be buried by dung beetles. These seeds can thus benefit from a better protection against predation and a more suitable microenvironment for germination, potentially enhancing seedling recruitment.Los coleópteros coprófagos desempeñan diversas funciones en los ecosistemas, siendo probablemente su papel como dispersores secundarios de semillas uno de los más complejos debido a que diversos factores como características de las semillas, patrón de defecación del dispersor primario, hábitat y estación pueden afectar de muchas maneras la interacción semilla-coleóptero. Poco se conoce sobre el destino de las semillas dispersadas en heces pequeñas. El objetivo de este estudio fue determinar los efectos de estos factores sobre la comunidad de coleópteros (composición de especies, número y tamaño de individuos) y sus consecuencias sobre la ocurrencia de entierro y su profundidad para semillas dispersadas por dos especies de “pichicos”. En un bosque tropical húmedo peruano se colectaron coleópteros con 299 trampas de caída cebadas con heces para caracterizar la comunidad de coleópteros. Se marcaron in situ y se protegieron con malla 551 semillas dispersadas en las heces para evaluar la ocurrencia de semillas enterradas y la profundidad de entierro. De las semillas marcadas, 22.5 por ciento fueron enterradas por coleópteros después de dos días. Se observó un efecto significativo de la cantidad de materia fecal, estación, hora de defecación y hábitat sobre el número de individuos y especies de coleópteros, así como también en la ocurrencia y profundidad de entierro de las semillas. La especie de “pichico” solo influyó en el número y el tamaño de los coleópteros coprófagos. Este ciclo de dispersión de semillas es particularmente importante para la regeneración del bosque: semillas de diferentes tamaños dispersadas por los “pichicos” en el bosque secundario pueden ser enterradas por los coleópteros coprófagos. Esas semillas obtienen una mejor protección contra los predadores y un microambiente más apropiado para la germinación, aumentando potencialmente el reclutamiento de las plántulas.
Intensification of framing practices after the Second World War has led to wide scale loss of sem... more Intensification of framing practices after the Second World War has led to wide scale loss of semi-natural grasslands throughout the UK. Flood-plain meadows (NVC MG4 Alopecurus pratensis–Sanguisorba officinalis grassland) suffered under these changes in agricultural management, and now cover an area of <1500 ha in England and Wales. In 1985, an experiment was initiated at Somerford Mead, Oxford, with the target of re-creating MG4 grassland. The grassland was established with a sown seed mixture harvested from local MG4 grassland. A replicated block experiment was set up to look at the effects of sheep, cattle and no grazing on the establishment of the target floral community. In 2002, the effects of these management regimes on beetle communities were investigated. Grazing regime was seen to be the primary determinant of abundance, species richness and species assemblage of the beetle population. Vegetation structure was also found to influence beetle diversity. The percentage cover of the legume Trifolium repens had important effects on beetle community assemblage, whilst Trifolium pratense was strongly correlated with the abundance of three common phytophagous beetles. This study provides a preliminary investigation into the responses of beetle communities to management intended for the re-creation of the plant communities of this threatened grassland habitat.
Skip to Main Content. Wiley Online Library will be disrupted on 7 July from 10:00-12:00 BST (05:0... more Skip to Main Content. Wiley Online Library will be disrupted on 7 July from 10:00-12:00 BST (05:00-07:00 EDT) for essential maintenance. ...
The morphology of the labrum (epipharynx, ikrioma and aboral surface) of adult Aphodiini is figur... more The morphology of the labrum (epipharynx, ikrioma and aboral surface) of adult Aphodiini is figured and discussed. An updated glossary of the constitutive parts is presented.
A key challenge for tropical conservation biologists is to assess how forest management practices... more A key challenge for tropical conservation biologists is to assess how forest management practices affect biodiversity and associated ecosystem functions. Dung beetles (Scarabaeidae: Scarabaeinae) provide an ideal focal guild for such studies. We compared dung beetle assemblages and experimentally assessed rates of dung removal and seed burial in undisturbed forest, low-intensity selectively logged forest under sustainable forest management, and high-intensity logged forest, not under sustainable management in ...
Natural sciences conservation group newsletter, Jan 1, 2000
Close Document Image Close Document Printer Image Print This Document! Conservation Information N... more Close Document Image Close Document Printer Image Print This Document! Conservation Information Network (BCIN). Author: Mann, Darren J. Title Article/Chapter: &quot;Pests from non-collection sources&quot; Title of Source: Natural ...
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