@article{PechouskovaDammhahnBrameieretal.2015,
  author    = {Pechouskova, Eva and Dammhahn, Melanie and Brameier, Markus and Fichtel, Claudia and Kappeler, Peter M. and Huchard, Elise},
  title     = {MHC class II variation in a rare and ecological specialist mouse lemur reveals lower allelic richness and contrasting selection patterns compared to a generalist and widespread sympatric congener},
  series = {Immunogenetics},
  volume    = {67},
  journal   = {Immunogenetics},
  number    = {4},
  publisher = {Springer},
  address   = {New York},
  issn      = {0093-7711},
  doi       = {10.1007/s00251-015-0827-4},
  pages     = {229 -- 245},
  year      = {2015},
  abstract  = {The polymorphism of immunogenes of the major histocompatibility complex (MHC) is thought to influence the functional plasticity of immune responses and, consequently, the fitness of populations facing heterogeneous pathogenic pressures. Here, we evaluated MHC variation (allelic richness and divergence) and patterns of selection acting on the two highly polymorphic MHC class II loci (DRB and DQB) in the endangered primate Madame Berthe's mouse lemur (Microcebus berthae). Using 454 pyrosequencing, we examined MHC variation in a total of 100 individuals sampled over 9 years in Kirindy Forest, Western Madagascar, and compared our findings with data obtained previously for its sympatric congener, the grey mouse lemur (Microcebus murinus). These species exhibit a contrasting ecology and demography that were expected to affect MHC variation and molecular signatures of selection. We found a lower allelic richness concordant with its low population density, but a similar level of allelic divergence and signals of historical selection in the rare feeding specialist M. berthae compared to the widespread generalist M. murinus. These findings suggest that demographic factors may exert a stronger influence than pathogen-driven selection on current levels of allelic richness in M. berthae. Despite a high sequence similarity between the two congeners, contrasting selection patterns detected at DQB suggest its potential functional divergence. This study represents a first step toward unravelling factors influencing the adaptive divergence of MHC genes between closely related but ecologically differentiated sympatric lemurs and opens new questions regarding potential functional discrepancy that would explain contrasting selection patterns detected at DQB.},
  language  = {en}
}
@article{DammhahnRakotondramananaGoodman2015,
  author    = {Dammhahn, Melanie and Rakotondramanana, Claude Fabienne and Goodman, Steven M.},
  title     = {Coexistence of morphologically similar bats (Vespertilionidae) on Madagascar: stable isotopes reveal fine-grained niche differentiation among cryptic species},
  series = {Journal of tropical ecology},
  volume    = {31},
  journal   = {Journal of tropical ecology},
  publisher = {Cambridge Univ. Press},
  address   = {New York},
  issn      = {0266-4674},
  doi       = {10.1017/S0266467414000741},
  pages     = {153 -- 164},
  year      = {2015},
  abstract  = {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.},
  language  = {en}
}
@article{HamalainenDammhahnAujardetal.2015,
  author    = {Hamalainen, Anni and Dammhahn, Melanie and Aujard, Fabienne and Kraus, Cornelia},
  title     = {Losing grip: Senescent decline in physical strength in a small-bodied primate in captivity and in the wild},
  series = {Experimental gerontology},
  volume    = {61},
  journal   = {Experimental gerontology},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0531-5565},
  doi       = {10.1016/j.exger.2014.11.017},
  pages     = {54 -- 61},
  year      = {2015},
  abstract  = {Muscle strength reflects physical functioning, declines at old age and predicts health and survival in humans and laboratory animals. Age-associated muscle deterioration causes loss of strength and may impair fitness of wild animals. However, the effects of age and life-history characteristics on muscle strength in wild animals are unknown. We investigated environment-and sex-specific patterns of physical functioning by measuring grip strength in wild and captive gray mouse lemurs. We expected more pronounced strength senescence in captivity due to condition-dependent, extrinsic mortality found in nature. Males were predicted to be stronger but potentially experience more severe senescence than females as predicted by life history theory. We found similar senescent declines in captive males and females as well as wild females, whereas wild males showed little decline, presumably due to their early mortality. Captive animals were generally weaker and showed earlier declines than wild animals. Unexpectedly, females tended to be stronger than males, especially in the reproductive season. Universal intrinsic mechanisms (e. g. sarcopenia) likely cause the similar patterns of strength loss across settings. The female advantage in muscle strength merits further study; it may follow higher reproductive investment by males, or be an adaptation associated with female social dominance.},
  language  = {en}
}