02408nas a2200229   4500008004100000245013600041210006900177300001200246490000700258520158000265653001801845653001801863653001601881653002101897653001801918653002101936100002001957700002301977700002002000700002002020856013802040       2007                        eng d00aRoles of endothermy in niche differentiation for ball-rolling dung beetles (Coleoptera: Scarabaeidae) along an altitudinal gradient0 aRoles of endothermy in niche differentiation for ballrolling dun  a544-5510 v323 a    1.   An analysis of whether niche differentiation in ball-rolling dung beetles can be explained by the way in which they regulate their body temperature was conducted.  2.    A priori  assumptions were: (i) if thermoregulation affects niche partitioning, sympatric species must have different endothermic strategies that minimise encounters; or, alternatively (ii) if two co-occurring species show the same thermoregulation pattern and their flight periods overlap, they might be avoiding competition by exhibiting different resource preferences or different food relocation behaviour.  3.   The ball-rolling dung beetles studied showed a hierarchical structure based on the species’ endothermic capacity, measured as temperature excess [ T  ex  = difference between body temperature ( T  b ) and ambient temperature ( T  a )]. Those with a high  T  ex  (10 – 15 °C) were located exclusively at altitudes >1000 m a.s.l. On the coastal plains, species with a high  T  ex  were restricted to flying at night when the  T  a  was lower. Species with a lower  T  ex  (less than 10 °C higher than  T  a ) were found in the coastal plains zone.  4.   Where there was sympatry with similar trophic habits, the species involved showed very different thermal niches, and where there was significant overlap of thermal niches between sympatric species, trophic habits of species were very different.  5.   The results suggest that it is possible to use the concept of the thermal niche as a tool to explain interspecific interactions and the spatial distribution of species.  10aEcophysiology10aniche overlap10aNull models10aScarabaeoidea  .10athermal niche10athermoregulation1 aVerdu, Jose, R.1 aArellano, Lucrecia1 aNuma, Catherine1 aMico, Estefania  uhttps://scarabnet.myspecies.info/roles-endothermy-niche-differentiation-ball-rolling-dung-beetles-coleoptera-scarabaeidae-along-altit02525nas a2200253   4500008004100000245009700041210006900138300001200207490000800219520166500227653002901892653001501921653002701936653002201963653001701985653001702002100002002019700002402039700002702063700002002090700002102110700002202131856011802153       2007                        eng d00aGrazing promotes dung beetle diversity in the xeric landscape of a Mexican Biosphere Reserve0 aGrazing promotes dung beetle diversity in the xeric landscape of  a308-3170 v1403 aWe analyze the impact of grazing on dung beetle diversity at the Barranca de Metztitla ́ n Biosphere Reserve, a xeric ecosystem in central Mexico with a long history of use by humans. We compared the community structure, as well as the alpha and beta diversity between two cover conditions (open and closed vegetation) that represent the impact of grazing within a habitat, and between habitat types (submountainous and crassicaule scrublands). From 576 samples we collected 75,605 dung beetles belonging to 20 taxa. While mean species richness and diversity were different between habitat types, cumulative spe- cies richness was not. The effects of grazing on vegetation structure influenced the cumu- lative species richness and diversity of dung beetles in the submountainous scrubland, where grazing has created land mosaics of a grassland matrix with scrubland patches. This was not the case in the crassicaule scrubland where the impact of grazing is not as evident. Beta diversity significantly responds to the effects of grazing on habitat conditions. We dis- cuss the ecological factors that may promote these responses by landscape diversity com- ponents. We also identify the species that could act as useful indicators to monitor the effect of land management on biodiversity. Our results indicate cattle farming maintains a diversified land mosaic, and these areas support more diverse dung beetle ensembles than homogeneous areas of closed, shrubby vegetation cover. Thus, controlled grazing activity could certainly favour the conservation of dung beetle biodiversity and improve ecosystem functioning by maintaining dung decomposition rates. 10aAlpha and beta diversity10aAphodiinae10aBarranca de Metztitlan10aindicator species10aLand mosaics10aScarabaeidae1 aVerdu, Jose, R.1 aMoreno, Claudia, E.1 aSanchez-Rojas, Gerardo1 aNuma, Catherine1 aGalante, Eduardo1 aHalffter, Gonzalo  uhttps://scarabnet.myspecies.info/grazing-promotes-dung-beetle-diversity-xeric-landscape-mexican-biosphere-reserve02172nas a2200277   4500008004100000245013100041210006900172300001200241490000700253520120300260653002101463653002201484653002001506653001501526653002401541653002801565653001901593653001301612653001901625653001701644653002401661100002601685700002001711700002501731856013801756       2004                        eng d00aSeed dispersal and defecation patterns of Cebus capucinus and Alouatta palliata: consequences for seed dispersal effectiveness0 aSeed dispersal and defecation patterns of Cebus capucinus and Al  a535-5430 v203 aPrimates are primary seed dispersers for many tropical tree species. Different species of primates vary considerably in ranging and feeding behaviour, seed processing, and in seed defecation patterns. Here we compare the role of two arboreal primate species, howlers (Alouatta palliata), and white-faced monkeys (Cebus capucinus) as seed dispersers in a tropical dry forest in Costa Rica. We found that Cebus produce smaller defecations, spend shorter times feeding per tree, have longer seed dispersal distances, and produce a more scattered pattern of seed deposition in the forest than Alouatta. In addition, Cebus moved more frequently between trees, and consumed fruits of more species than Alouatta. We examined the consequences of the contrasting defecation patterns produced by Cebus and Alouatta on the early seed fate of Acacia collinsii. We found that quantity, but not the identity (Cebus vs. Alouatta) of faecal material affected post-dispersal activity. Seeds in scattered faeces, sufficiently apart from each other (the common defecation pattern of white-faced monkeys), had higher short-term survival than seeds in clumped patterns of faeces (the pattern associated with Alouatta). 10aAcacia collinsii10aAlouatta palliata10aCebus capucinus10aCosta Rica10adefecation patterns10adispersal effectiveness10apost-dispersal10aprimates10aseed dispersal10aseed removal10atropical dry forest1 aWehncke, Elisabet, V.1 aNuma, Catherine1 aDominguez, Cesar, A.  uhttps://scarabnet.myspecies.info/seed-dispersal-and-defecation-patterns-cebus-capucinus-and-alouatta-palliata-consequences-seed-dispe