How the environment shapes animal signals: a test of the acoustic adaptation hypothesis in frogs.

Long-distance acoustic signals are widely used in animal communication systems and, in many cases, are essential for reproduction. The acoustic adaptation hypothesis (AAH) implies that acoustic signals should be selected for further transmission and better content integrity under the acoustic constraints of the habitat in which they are produced. In this study, we test predictions derived from the AAH in frogs. Specifically, we focus on the difference between torrent frogs and frogs calling in less noisy habitats. Torrents produce sounds that can mask frog vocalizations and constitute a major acoustic constraint on call evolution. We combine data collected in the field, material from scientific collections and the literature for a total of 79 primarily Asian species, of the families Ranidae, Rhacophoridae, Dicroglossidae and Microhylidae. Using phylogenetic comparative methods and including morphological and environmental potential confounding factors, we investigate putatively adaptive call features in torrent frogs. We use broad habitat categories as well as fine-scale habitat measurements and test their correlation with six call characteristics. We find mixed support for the AAH. Spectral features of torrent frog calls are different from those of frogs calling in other habitats and are related to ambient noise levels, as predicted by the AAH. However, temporal call features do not seem to be shaped by the frogs' calling habitats. Our results underline both the complexity of call evolution and the need to consider multiple factors when investigating this issue.

Crossing the Rift valley: using complete mitogenomes to infer the diversification and biogeographic history of ethiopian highlands Ptychadena (anura: Ptychadenidae).

The Ethiopian Highlands are considered a biodiversity hotspot, harboring a high number of endemic species. Some of the endemic species probably diversified in situ; this is, for example, the case of a monophyletic clade containing 12 known species of grass frogs of the genus Ptychadena. The different species occur at elevations ranging from 1,500 to above 3,400 m and constitute excellent models to study the process of diversification in the highlands as well as adaptations to high elevations. In this study, we sampled 294 specimens across the distribution of this clade and used complete mitogenomes and genome-wide SNP data to better understand how landscape features influenced the population structure and dispersal of these grass frogs across time and space. Using phylogenetic inference, population structure analyses, and biogeographic reconstructions, we found that the species complex probably first diversified on the south-east side of the Great Rift Valley. Later on, species dispersed to the north-west side, where more recent diversification occurred. We further demonstrate that Ptychadena species have dispersed across the Great Rift Valley at different times. Our analyses allowed for a more complete understanding of the contribution of geological events, biogeographic barriers and climatic changes as drivers of species diversification and adaptation in this important biogeographic region.

[Video: An innovation for developmental care in the neonatal intensive care unit]. / La surveillance vidéo : une innovation au service des soins de développement en unité de soins intensifs de néonatologie.

INTRODUCTION: Our neonatal intensive care unit (NICU) was designed with a web-camera system in eight private rooms and four open wards. This equipment was installed to both guarantee children's safety in the NICU and promote the bond between the child and his/her family through a viewing service permitted by an Internet access. METHOD: We evaluated the web-camera system in its 5th year with two types of users. The nursing staff was asked about use of the video and its impact on their management of NICU patients. Questionnaires for parents sought to determine how they used the system and their feelings about it. RESULTS: Ninety-three percent of the nursing staff used the web-camera system to provide medical supervision or to comply with developmental care, mainly to respect the baby's natural rhythm by initiating care only when the baby showed signs of awakening. The web-camera system allowed them to observe the baby, verify his/her good body position, and spot discomfort situations. It helped provide a faster and personalized answer that was adjusted to the baby's needs. Sixty-one percent of the parents used the remote connection, half of them to present the child to the family. Only 17% of parents were embarrassed by the cameras; 88% of parents thought that the video was an additional safety device in NICU management. CONCLUSION: The web-camera system appeared to be an interesting technology in the NICU to support developmental care when children could be put in private rooms. It helped staff react faster to situations that created an inappropriate stimulation for the baby. It also allowed to them to respect the baby's natural rhythm. It reassured nursing staff and parents and it facilitated the baby's integration into the family.