Correlates of genetic monogamy in socially monogamous mammals: insights from Azara's owl monkeys

Understanding the evolution of mating systems, a central topic in evolutionary biology for more than 50 years, requires examining the genetic consequences of mating and the relationships between social systems and mating systems. Among pair-living mammals, where genetic monogamy is extremely rare, the extent of extra-group paternity rates has been associated withmale participation in infant care, strength of the pair bond and length of the breeding season. This study evaluated the relationship between two of those factors and the genetic mating system of socially monogamous mammals, testing predictions that male care and strength of pair bond would be negatively correlated with rates of extra-pair paternity (EPP). Autosomal microsatellite analyses provide evidence for genetic monogamy in a pair-living primate with bi-parental care, the Azara’s owl monkey (Aotus azarae). A phylogenetically corrected generalized least square analysis was used to relate male care and strength of the pair bond to their genetic mating system (i.e. proportions of EPP) in 15 socially monogamous mammalian species. The intensity of male care was correlated with EPP rates in mammals, while strength of pair bond failed to reach statistical significance. Our analyses showthat, once social monogamy has evolved, paternal care, and potentially also close bonds, may facilitate the evolution of genetic monogamy.German Science Foundation (HU 1746/2-1); Wenner-Gren Foundation; L.S.B. Leakey Foundation;National Geographic Society; National Science Foundation (BCS-0621020, 1219368, and 1232349); the University of Pennsylvania Research Foundation; the Zoological Society of San Dieg

Self-Organized Nanogratings for Large-Area Surface Plasmon Polariton Excitation and Surface-Enhanced Raman Spectroscopy Sensing

Surface plasmon polaritons (SPP) are exploited due to their intriguing properties for the fabrication and miniaturization of photonic circuits, for surface-enhanced spectroscopy and imaging beyond the diffraction limit. However, excitation of these plasmonic modes by direct illumination is forbidden by energy/momentum conservation rules. One strategy to overcome this limitation relies on diffraction gratings to match the wavevector of the incoming photons with that of propagating SPP excitations. The main limit of the approaches so far reported in the literature is that they rely on highly ordered diffraction gratings fabricated by means of demanding nanolithographic processes. In this work, we demonstrate that an innovative, fully self-organized method based on wrinkling-assisted ion-beam sputtering can be exploited to fabricate large-area (cm2 scale) nanorippled soda lime templates, which conformally support ultrathin Au films deposited by physical deposition. The self-organized patterns act as quasi-one-dimensional (1D) gratings characterized by a remarkably high spatial order, which properly matches the transverse photon coherence length. The gratings can thus enable the excitation of hybrid SPP modes confined at the Au/dielectric interfaces, with a resonant wavelength that can be tuned by modifying the grating period, photon incidence angle, or, potentially, the choice of the thin-film conductive material. Surface-enhanced Raman scattering experiments show promising gains in the range of 103, which are competitive, even before a systematic optimization of the sample fabrication parameters, with state-of-the art lithographic systems, demonstrating the potential of such templates for a broad range of optoelectronic applications aiming at plasmon-enhanced photon harvesting for molecular or biosensing

Gut microbiota variations in wild yellow baboons (Papio cynocephalus) are associated with sex and habitat disturbance

Although male and female mammals differ in biological traits and functional needs, the contribution of this sexual dimorphism to variations in gut bacteria and fungi (gut microbiota) in relation to habitat type has not been fully examined. To understand whether the combination of sex and habitat affects gut microbiota variation, we analyzed 40 fecal samples of wild yellow baboons (Papio cynocephalus) living in contrasting habitat types (intact, well-protected vs. fragmented, less protected forests) in the Udzungwa Mountains of Tanzania. Sex determination was performed using the marker genes SRY (Sex-determining Region Y) and DDX3X-DDX3Y (DEAD-Box Helicase 3). Samples were attributed to 34 individuals (19 females and 15 males) belonging to five social groups. Combining the results of sex determination with two amplicon sequencing datasets on bacterial (V1-V3 region of the 16S rRNA gene) and fungal (ITS2) gut communities, we found that overall, baboon females had a significantly higher gut bacterial richness compared to males. Beta diversity estimates indicated that bacterial composition was significantly different between males and females, and this was true for individuals from both well- and less protected forests. Our results highlight the combined role of sex and habitat type in shaping variation in gut microbial communities in wild non-human primates

Interaction induced delocalisation for two particles in a periodic potential

We consider two interacting particles evolving in a one-dimensional periodic structure embedded in a magnetic field. We show that the strong localization induced by the magnetic field for particular values of the flux per unit cell is destroyed as soon as the particles interact. We study the spectral and the dynamical aspects of this transition.Comment: 4 pages, 5 EPS figures, minor misprints correcte

Gut microbial functions are impacted by habitat: implications for the conservation of non-human primates

We investigate the effect of forest fragmentation on gut microbiota functions and dietary adaptations of two non-human primate species in the Udzungwa Mountains of Tanzania using whole-genome shotgun sequencing. The Udzungwa red colobus (Procolobus gordonorum) is an endangered species with a restricted folivorous (leaf-eating) diet, while the yellow baboon (Papio cynocephalus) is a species of least concern with a highly diverse omnivorous diet. We identified several microbial pathways that were enriched or decreased in a fragmented forest patch compared to an intact forest, indicating functional adaptations of gut bacteria. The gut microbiota of the Udzungwa red colobus, in particular, shows a high sensitivity to habitat changes, which may be linked to its strictly folivorous feeding strategy. By contrast, the yellow baboon displays greater tolerance to habitat changes by showing a lower impact on their gut microbes, which is likely caused by its more varied diet. To investigate habitat-associated diet in detail, in an ongoing analysis, we aim to reconstruct dietary composition from the same shotgun sequencing samples. We will also present novel results showing the potential and the limits of identifying diet and host characteristics from faecal samples, and hence, the usefulness of this shotgun approach to conservation issues

Interactions between parasitic helminths and gut microbiota in wild tropical primates from intact and fragmented habitats

7openInternationalBothThe mammalian gastrointestinal tract harbours a highly complex ecosystem composed of a variety of micro- (bacteria, fungi, viruses, protozoans) and macro-organisms (helminths). Although most microbiota research focuses on the variation of single gut components, the crosstalk between components is still poorly characterized, especially in hosts living under natural conditions. We investigated the gut micro-biodiversity (bacteria, fungi and helminths) of 158 individuals of two wild non-human primates, the Udzungwa red colobus (Procolobus gordonorum) and the yellow baboon (Papio cynocephalus). These species have contrasting diets and lifestyles, but live sympatrically in both human-impacted and pristine forests in the Udzungwa Mountains of Tanzania. Using non-invasive faecal pellets, helminths were identified using standard microscopy while bacteria and fungi were characterized by sequencing the V1–V3 variable region of the 16S rRNA gene for bacteria and the ITS1–ITS2 fragment for fungi. Our results show that both diversity and composition of bacteria and fungi are associated with variation in helminth presence. Although interactions differed by habitat type, in both primates we found that Strongyloides was negatively associated and Trichuris was positively associated with bacterial and fungal richness. To our knowledge, this is one of the few studies demonstrating an interaction between helminth and gut microbiota communities in wild non-human primates.openBarelli, Claudia; Donati, Claudio; Albanese, Davide; Pafčo, Barbora; Modrý, David; Rovero, Francesco; Hauffe, Heidi C.Barelli, C.; Donati, C.; Albanese, D.; Pafčo, B.; Modrý, D.; Rovero, F.; Hauffe, H.C

Sex predicts gut microbiota variations in wild yellow baboons (Papio cynocephalus)

The role of gut microbiota diversity in animal ecology and conservation has become a key topic, especially since the contribution of these bacterial and fungal communities to host growth and health has been recently recognized. Most investigations in wildlife have focused on the study of extrinsic (e.g., diet, habitat) rather than intrinsic factors (e.g., sex, genetic background) affecting variation in animal gut communities. However, since male and female mammals often differ in biological traits and functional needs, sex is likely to play a major role in gut microbiota variation. Here, we evaluated if and how sex is associated with the gut microbiota richness and composition of wild yellow baboons (Papio cynocephalus) living in two habitat types, protected and unprotected forests of the Udzungwa Mountains in Tanzania. To understand whether sex and habitat type affect gut microbiota variation, we determined the sex of 34 yellow baboons (19 females and 15 males) from fecal pellets collected non-invasively using two marker genes (SRY and DDX3X). We then combined these results with amplicon sequencing datasets focusing on bacterial (V3-V4 region of the 16S rRNA gene) and fungal (ITS1-ITS2) communities of the same pellets. We found that females had gut microbiotas with a higher bacterial richness [Kruskal test; Shannon (alpha diversity): P = 0.010] and different composition [ANOVA; weighted Unifrac (beta diversity): P = 0.030] compared to males, in agreement with the strong morphological and behavioural dimorphisms shown between sexes of this species. Furthermore, forest type had a greater impact on females than males, such that the gut microbiotas of females from the two forests differed significantly in fungal composition [pairwise adonis test; Bray-Curtis: P = 0.02] and bacterial richness [pairwise Wilcoxon Rank Sum test; Shannon: P = 0.023], while those of males did not. These results indicated that the impact of habitat disturbance varied with sex, suggesting that intrinsic biological factors should be carefully considered when investigating wild animal biodiversity at any scale, and that such intraspecific variation could impact the outcome of conservation actions. However, research on the metabolic pathways, through shotgun sequencing, are encouraged to verify whether greater gut bacterial richness, such as those observed in baboon females, may translate into a greater diversity of metabolic functions

Self-Organized Nanorod Arrays for Large-Area Surface-Enhanced Infrared Absorption

Capabilities of highly sensitive surface-enhanced infrared absorption (SEIRA) spectroscopy are demonstrated by exploiting large-area templates (cm2) based on self-organized (SO) nanorod antennas. We engineered highly dense arrays of gold nanorod antennas featuring polarization-sensitive localized plasmon resonances, tunable over a broadband near- and mid-infrared (IR) spectrum, in overlap with the so-called "functional group" window. We demonstrate polarization-sensitive SEIRA activity, homogeneous over macroscopic areas and stable in time, by exploiting prototype self-assembled monolayers of IR-active octadecanthiol (ODT) molecules. The strong coupling between the plasmonic excitation and molecular stretching modes gives rise to characteristic Fano resonances in SEIRA. The SO engineering of the active hotspots in the arrays allows us to achieve signal amplitude improved up to 5.7%. This figure is competitive to the response of lithographic nanoantennas and is stable when the optical excitation spot varies from the micro- to macroscale, thus enabling highly sensitive SEIRA spectroscopy with cost-effective nanosensor devices