TY - GEN A1 - Dammhahn, Melanie A1 - Goodman, Steven M. T1 - Trophic niche differentiation and microhabitat utilization revealed by stable isotope analyses in a dry-forest bat assemblage at Ankarana, northern Madagascar T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - Bats are important components in tropical mammal assemblages. Unravelling the mechanisms allowing multiple syntopic bat species to coexist can provide insights into community ecology. However, dietary information on component species of these assemblages is often difficult to obtain. Here we measuredstable carbon and nitrogen isotopes in hair samples clipped from the backs of 94 specimens to indirectly examine whether trophic niche differentiation and microhabitat segregation explain the coexistence of 16 bat species at Ankarana, northern Madagascar. The assemblage ranged over 4.4% in delta N-15 and was structured into two trophic levels with phytophagous Pteropodidae as primary consumers (c. 3% enriched over plants) and different insectivorous bats as secondary consumers (c. 4% enriched over primary consumers). Bat species utilizing different microhabitats formed distinct isotopic clusters (metric analyses of delta C-13-delta N-15 bi-plots), but taxa foraging in the same microhabitat did not show more pronounced trophic differentiation than those occupying different microhabitats. As revealed by multivariate analyses, no discernible feeding competition was found in the local assemblage amongst congeneric species as compared with non-congeners. In contrast to ecological niche theory, but in accordance with studies on New and Old World bat assemblages, competitive interactions appear to be relaxed at Ankarana and not a prevailing structuring force. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 595 KW - Ankarana KW - canopy effect KW - Chiroptera KW - coexistence KW - community structure KW - congeneric species KW - dry deciduous forest KW - Madagascar Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-415157 SN - 1866-8372 SP - 97 EP - 109 ER - TY - JOUR A1 - Gaubert, Philippe A1 - Patel, Riddhi P. A1 - Veron, Geraldine A1 - Goodman, Steven M. A1 - Willsch, Maraike A1 - Vasconcelos, Raquel A1 - Lourenco, Andre A1 - Sigaud, Marie A1 - Justy, Fabienne A1 - Joshi, Bheem Dutt A1 - Fickel, Jörns A1 - Wilting, Andreas T1 - Phylogeography of the Small Indian Civet and Origin of Introductions to Western Indian Ocean Islands JF - The journal of heredity : official journal of the American Genetic Association N2 - The biogeographic dynamics affecting the Indian subcontinent, East and Southeast Asia during the Plio-Pleistocene has generated complex biodiversity patterns. We assessed the molecular biogeography of the small Indian civet (Viverricula indica) through mitogenome and cytochrome b + control region sequencing of 89 historical and modern samples to (1) establish a time-calibrated phylogeography across the species’ native range and (2) test introduction scenarios to western Indian Ocean islands. Bayesian phylogenetic analyses identified 3 geographic lineages (East Asia, sister-group to Southeast Asia and the Indian subcontinent + northern Indochina) diverging 3.2–2.3 million years ago (Mya), with no clear signature of past demographic expansion. Within Southeast Asia, Balinese populations separated from the rest 2.6–1.3 Mya. Western Indian Ocean populations were assigned to the Indian subcontinent + northern Indochina lineage and had the lowest mitochondrial diversity. Approximate Bayesian computation did not distinguish between single versus multiple introduction scenarios. The early diversification of the small Indian civet was likely shaped by humid periods in the Late Pliocene–Early Pleistocene that created evergreen rainforest barriers, generating areas of intra-specific endemism in the Indian subcontinent, East, and Southeast Asia. Later, Pleistocene dispersals through drier conditions in South and Southeast Asia were likely, giving rise to the species’ current natural distribution. Our molecular data supported the delineation of only 4 subspecies in V. indica, including an endemic Balinese lineage. Our study also highlighted the influence of prefirst millennium AD introductions to western Indian Ocean islands, with Indian and/or Arab traders probably introducing the species for its civet oil. KW - Asia KW - biogeography KW - civet oil KW - mtDNA KW - Plio-Pleistocene KW - Viverridae Y1 - 2016 U6 - https://doi.org/10.1093/jhered/esw085 SN - 0022-1503 SN - 1465-7333 VL - 108 SP - 270 EP - 279 PB - Oxford Univ. Press CY - Cary ER - TY - JOUR A1 - Dammhahn, Melanie A1 - Rakotondramanana, Claude Fabienne A1 - Goodman, Steven M. T1 - Coexistence of morphologically similar bats (Vespertilionidae) on Madagascar: stable isotopes reveal fine-grained niche differentiation among cryptic species JF - Journal of tropical ecology N2 - Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0% in delta N-15, i.e. two trophic levels, and 4.2% in delta C-13 with a community mean of 11.3% in delta N-15 and - 21.0% in delta C-13. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (delta N-15: 2.4%, delta C-13: 1.0%) with a community mean of 8.0% delta N-15 and - 21.7% in delta C-13. Multivariate analyses and residual permutation of Euclidian distances in delta C-13- delta N-15 bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa. KW - Chiroptera KW - community structure KW - congeneric species KW - ecological niches KW - migration KW - Neoromicia KW - Pipistrellus KW - Scotophilus KW - stable carbon KW - stable nitrogen Y1 - 2015 U6 - https://doi.org/10.1017/S0266467414000741 SN - 0266-4674 SN - 1469-7831 VL - 31 SP - 153 EP - 164 PB - Cambridge Univ. Press CY - New York ER - TY - GEN A1 - Dammhahn, Melanie A1 - Rakotondramanana, Claude Fabienne A1 - Goodman, Steven M. T1 - Coexistence of morphologically similar bats (Vespertilionidae) on Madagascar BT - stable isotopes reveal fine-grained niche differentiation among cryptic species T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Based on niche theory, closely related and morphologically similar species are not predicted to coexist due to overlap in resource and habitat use. Local assemblages of bats often contain cryptic taxa, which co-occur despite notable similarities in morphology and ecology. We measured in two different habitat types on Madagascar levels of stable carbon and nitrogen isotopes in hair (n = 103) and faeces (n = 57) of cryptic Vespertilionidae taxa to indirectly examine whether fine-grained trophic niche differentiation explains their coexistence. In the dry deciduous forest (Kirindy), six sympatric species ranged over 6.0% in delta N-15, i.e. two trophic levels, and 4.2% in delta C-13 with a community mean of 11.3% in delta N-15 and - 21.0% in delta C-13. In the mesic forest (Antsahabe), three sympatric species ranged over one trophic level (delta N-15: 2.4%, delta C-13: 1.0%) with a community mean of 8.0% delta N-15 and - 21.7% in delta C-13. Multivariate analyses and residual permutation of Euclidian distances in delta C-13- delta N-15 bi-plots revealed in both communities distinct stable isotope signatures and species separation for the hair samples among coexisting Vespertilionidae. Intraspecific variation in faecal and hair stable isotopes did not indicate that seasonal migration might relax competition and thereby facilitate the local co-occurrence of sympatric taxa. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 590 KW - Chiroptera KW - community structure KW - congeneric species KW - ecological niches KW - migration KW - Neoromicia KW - Pipistrellus KW - Scotophilus KW - stable carbon KW - stable nitrogen Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-414729 SN - 1866-8372 IS - 590 ER - TY - GEN A1 - Dammhahn, Melanie A1 - Randriamoria, Toky M. A1 - Goodman, Steven M. T1 - Broad and flexible stable isotope niches in invasive non-native Rattus spp. in anthropogenic and natural habitats of central eastern Madagascar T2 - Postprints der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe N2 - Background: Rodents of the genus Rattus are among the most pervasive and successful invasive species, causing major vicissitudes in native ecological communities. A broad and flexible generalist diet has been suggested as key to the invasion success of Rattus spp. Here, we use an indirect approach to better understand foraging niche width, plasticity, and overlap within and between introduced Rattus spp. in anthropogenic habitats and natural humid forests of Madagascar. Results: Based on stable carbon and nitrogen isotope values measured in hair samples of 589 individual rodents, we found that Rattus rattus had an extremely wide foraging niche, encompassing the isotopic space covered by a complete endemic forest-dwelling Malagasy small mammal community. Comparisons of Bayesian standard ellipses, as well as (multivariate) mixed-modeling analyses, revealed that the stable isotope niche of R. rattus tended to change seasonally and differed between natural forests and anthropogenic habitats, indicating plasticity in feeding niches. In co-occurrence, R. rattus and Rattus norvegicus partitioned feeding niches. Isotopic mismatch of signatures of individual R. rattus and the habitat in which they were captured, indicate frequent dispersal movements for this species between natural forest and anthropogenic habitats. Conclusions: Since R. rattus are known to transmit a number of zoonoses, potentially affecting communities of endemic small mammals, as well as humans, these movements presumably increase transmission potential. Our results suggest that due to their generalist diet and potential movement between natural forest and anthropogenic habitats, Rattus spp. might affect native forest-dependent Malagasy rodents as competitors, predators, and disease vectors. The combination of these effects helps explain the invasion success of Rattus spp. and the detrimental effects of this genus on the endemic Malagasy rodent fauna. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 722 KW - Bayesian standard ellipse KW - coexistence KW - habitat use KW - humid forest KW - invasion ecology KW - invasive species KW - Rattus rattus KW - Rattus norvegicus KW - rodents KW - fur KW - stable carbon isotope KW - stable nitrogen isotope Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-429419 SN - 1866-8372 IS - 722 ER - TY - JOUR A1 - Dammhahn, Melanie A1 - Randriamoria, Toky M. A1 - Goodman, Steven M. T1 - Broad and flexible stable isotope niches in invasive non-native Rattus spp. in anthropogenic and natural habitats of central eastern Madagascar JF - BMC ecology N2 - Background: Rodents of the genus Rattus are among the most pervasive and successful invasive species, causing major vicissitudes in native ecological communities. A broad and flexible generalist diet has been suggested as key to the invasion success of Rattus spp. Here, we use an indirect approach to better understand foraging niche width, plasticity, and overlap within and between introduced Rattus spp. in anthropogenic habitats and natural humid forests of Madagascar. Results: Based on stable carbon and nitrogen isotope values measured in hair samples of 589 individual rodents, we found that Rattus rattus had an extremely wide foraging niche, encompassing the isotopic space covered by a complete endemic forest-dwelling Malagasy small mammal community. Comparisons of Bayesian standard ellipses, as well as (multivariate) mixed-modeling analyses, revealed that the stable isotope niche of R. rattus tended to change seasonally and differed between natural forests and anthropogenic habitats, indicating plasticity in feeding niches. In co-occurrence, R. rattus and Rattus norvegicus partitioned feeding niches. Isotopic mismatch of signatures of individual R. rattus and the habitat in which they were captured, indicate frequent dispersal movements for this species between natural forest and anthropogenic habitats. Conclusions: Since R. rattus are known to transmit a number of zoonoses, potentially affecting communities of endemic small mammals, as well as humans, these movements presumably increase transmission potential. Our results suggest that due to their generalist diet and potential movement between natural forest and anthropogenic habitats, Rattus spp. might affect native forest-dependent Malagasy rodents as competitors, predators, and disease vectors. The combination of these effects helps explain the invasion success of Rattus spp. and the detrimental effects of this genus on the endemic Malagasy rodent fauna. KW - Bayesian standard ellipse KW - Coexistence KW - Habitat use KW - Humid forest KW - Invasion ecology KW - Invasive species KW - Rattus rattus KW - Rattus norvegicus KW - Rodents KW - Fur KW - Stable carbon isotope KW - Stable nitrogen isotope Y1 - 2017 U6 - https://doi.org/10.1186/s12898-017-0125-0 SN - 1472-6785 VL - 17 PB - BioMed Central CY - London ER -