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Depuis la découverte de l’universalité des capacités rythmiques chez les humains, les caractéristiques temporelles de la communication ont suscité grand intérêt chez les chercheurs. Les modèles rythmiques sont un outil précieux pour discriminer les espèces, les individus, ou pour le choix du partenaire. Une étude récente montre que les chants d'oiseaux et la musique humaine partagent la présence de catégories rythmiques lorsque les intervalles temporels sont distribués de manière catégorielle plutôt qu'uniforme. A la suite de cette étude, nous avons vérifié si les chants des indris (Indri indri), le seul lémurien chanteur, montraient des caractéristiques similaires. Nous avons mesuré les intervalles inter-onset (tk), délimités par les débuts de deux unités consécutives, et les rapports rythmiques entre ces intervalles (rk), calculés en divisant un intervalle par lui-même plus son adjacent : nous avons trouvé une distribution en trois clusters. Deux des clusters correspondaient à des catégories rythmiques 1:1 et 1:2, le troisième s'approchait du ratio 2:1. Nos résultats ont démontré pour la première fois qu'un autre primate produit des rythmes catégoriels, une capacité qui a probablement évolué par convergence chez les espèces qui chantent telles que les oiseaux, les indris et les humains. Il est fondamental de comprendre quelles caractéristiques de la communication sont partagées avec d'autres espèces pour en comprendre l’évolution. Dans cette perspective, grâce à la simplicité du traitement et de l'interprétation des données, notre étude s'est appuyée sur une approche analytique accessible qui pourrait ouvrir de nouveaux domaines d'investigation sur la communication chez les primates, ouvrant la voie à la reconstruction d'une phylogénie des capacités rythmiques au sein de cet ordre. Since the discovery that rhythmic abilities are universal in humans, temporal features of vocal communication have greatly interested researchers studying animal communication. Rhythmic patterns are a valuable tool for species discrimination, mate choice, and individual recognition. A recent study showed that bird songs and human music share rhythmic categories when a signal's temporal intervals are distributed categorically rather than uniformly. Following that study, we aimed to investigate whether songs of indris (Indri indri), the only singing lemur, may show similar features. We measured the inter-onset intervals (tk), delimited by the onsets of two consecutive units, and the rhythmic ratios between these intervals (rk), calculated by dividing an interval by itself plus its adjacent, and finded a three-cluster distribution. Two clusters corresponded to rhythmic categories at 1:1 and 1:2, and the third approached a 2:1 ratio. Our results demonstrated for the first time that another primate besides humans produces categorical rhythms, an ability likely evolved convergently among singing species such as songbirds, indris, and humans. Understanding which communicative features are shared with other species is fundamental to understanding how they have evolved. In this regard, thanks to the simplicity of data processing and interpretation, our study relied on an accessible analytical approach that could open up new branches of the investigation into primate communication, leading the way to reconstruct a phylogeny of rhythm abilities across the entire order.

Rhythm is a fundamental feature characterizing communicative displays, and recent studies showed that primate songs encompass categorical rhythms falling on small integer ratios observed in humans. We individually assessed the presence and sexual dimorphism of rhythmic categories, analyzing songs emitted by 39 wild indris. Considering the intervals between the units given during each song, we extracted 13556 interval ratios and found three peaks (at around 0.33, 0.47, and 0.70). Two peaks indicated rhythmic categories corresponding to small integer ratios (1:1, 2:1). All individuals showed a peak at 0.70, and most showed those at 0.47 and 0.33. In addition, we found sex differences in the peak at 0.47 only, with males showing lower values than females. This work investigates the presence of individual rhythmic categories in a non-human species; further research may highlight the significance of rhythmicity and untie selective pressures that guided its evolution across species, including humans.

Research on the gut microbiome may help with increasing our understanding of primate health with species’ ecology, evolution, and behavior. In particular, microbiome-related information has the potential to clarify ecology issues, providing knowledge in support of wild primates conservation and their associated habitats. Indri (Indri indri) is the largest extant living lemur of Madagascar. This species is classified as “critically endangered” by the IUCN Red List of Threatened Species, representing one of the world’s 25 most endangered primates. Indris diet is mainly folivorous, but these primates frequently and voluntarily engage in geophagy. Indris have never been successfully bred under human care, suggesting that some behavioral and/or ecological factors are still not considered from the ex situ conservation protocols. Here, we explored gut microbiome composition of 18 indris belonging to 5 different family groups. The most represented phyla were Proteobacteria 40.1 ± 9.5%, Bacteroidetes 28.7 ± 2.8%, Synergistetes 16.7 ± 4.5%, and Firmicutes 11.1 ± 1.9%. Further, our results revealed that bacterial alpha and beta diversity were influenced by indri family group and sex. In addition, we investigated the chemical composition of geophagic soil to explore the possible ecological value of soil as a nutrient supply. The quite acidic pH and high levels of secondary oxide-hydroxides of the soils could play a role in the folivorous diet’s gut detoxification activity. In addition, the high contents of iron and manganese found the soils could act as micronutrients in the indris’ diet. Nevertheless, the concentration of a few elements (i.e., calcium, sulfur, boron, nickel, sodium, and chromium) was higher in non-geophagic than in geophagic soils. In conclusion, the data presented herein provide a baseline for outlining some possible drivers responsible for the gut microbiome diversity in indris, thus laying the foundations for developing further strategies involved in indris’ conservation.

A karyological study conducted by both conventional and banding staining methods (Ag-NOR-, CMA3, and C-banding) evidenced a peculiar heterochromatin pattern on chromosomes of Moldovan specimens of the agile frog, Rana dalmatina. As is normal for all agile frogs, the Moldovan population presented 2n = 26 chromosomes, with NOR loci on the short arms of the third chromosome pair, but differed in showing heavy centromeric, CMA3 positive C-bands on the seventh chromosome pair, and light centromeric, DAPI positive C-bands on five chromosome pairs. In contrast, Moldovan specimens showed no significant difference in two segments of the 16S mitochondrial rRNA gene and in the S1 satellite DNA sequence and organization, in comparison with the GenBank deposited 16S rDNA and S1 DNA satellite sequences of R. dalmatina. Molecular similarity and chromosomal differences between agile frogs from Moldovan and extra-Moldovan populations are discussed.

The biting behaviour of the loggerhead sea turtle Caretta caretta, a high bycatch species by longline fishing gear, was studied on 30 wild specimens held temporarily at rescue centres. To account for repeated measures, the data were analysed using mixed-effects models. Chemicals from squid baits elicited significantly more biting behaviour than those from mackerel baits. Smaller turtles were more likely to bite than larger turtles. The findings add increasing evidence in support of the idea that the use of fish baits instead of squid baits could be a conservation measure to protect this endangered species from bycatch.Keywords: bycatch mitigation, Caretta caretta, chemoreception, endangered species, fisheriesAfrican Journal of Marine Science 2012, 34(2): 283–287

A panel of Italian neurologists of the Italian Society for the study of Dementias (SINDEM) discussed the recently proposed new lexicon for Alzheimer disease (AD) and the related diagnostic criteria for the different phases of the disease (Preclinical AD, prodromal AD and Alzheimer's dementia) (Dubois et al. in Lancet Neurol 6:734-746, 2007; in Lancet Neurol 9:1118-1127, 2010). The aim of this discussion was to reach a consensus, among the Italian neurologists involved in the study and care of persons with dementia, in particular in reference to the potential use of the proposed diagnostic criteria in clinical practice. After having critically revised the scientific evidence related to the new lexicon and to the new proposed diagnostic criteria, the panel concluded that the proposed new diagnostic criteria and the new proposed lexicon for AD are conceptually attractive. However, the evidence about the instrumental and laboratory markers for the diagnosis of the preclinical and asymptomatic states of the disease are, until to now, insufficient to support the routine clinical use of these investigations.