At the babbling stage, the syllable does not have the temporal characteristics of adult syllables because of the infant's limited oro-motor skills. This research aims to further our knowledge of syllable duration and temporal variability and their evolution with age as an indicator of the development of articulatory skills. The possible impact of syllable position, as well as that of type of intrasyllabic associations and intersyllabic articulatory changes on these parameters has also been tested. Oral productions of 22 French infants were recorded monthly from 8 to 14 months. 11 261 Consonant-Vowel (CV) syllables were annotated and temporally analyzed. The mean duration varied according to syllable position, but not to the intrasyllabic or intersyllabic articulatory changes. Moreover, the syllable duration decreased significantly from the age of 10 months onwards, whereas the temporal variability remained the same.

This study confirms the diet and determines the trophic position of the bentfin devil ray (Mobula thurstoni) and spinetail devil ray (Mobula japanica) in the south-west Gulf of California. There has been an active fishery in the area for these filter-feeding elasmobranchs, which are highly susceptible to exploitation due to low fecundity and long lifespan. However, information on their basic biology is scarce. δ13C and δ15N values of devil rays and zooplankton (sorted according to trophic level: herbivores, carnivores and omnivores) were determined over a period of 11 months, to allow for isotopic temporal variations in isotopic signals at the base of the food web. On the basis of fractionation factors we determined that bentfin and spinetail devil rays fed mainly on Nyctiphanes simplex, the most abundant euphausiid in neritic waters of the Gulf of California. The trophic positions obtained for the devil rays correspond to second level consumers.

Research was performed in Poggio Casciano Estate (Chianti area, central Italy) with the aim of defining a general approach to analyse the spatial variability of temperature at the microscale. Hourly data were collected from a network of 27 temperature stations covering an area of about 120 ha and determination coefficients r between station pairs on the basis of different geo-topographical factors were calculated. The data were analysed in order to investigate trends describing the spatial distribution of temperature inside the study area. The results pointed out a strong effect of some topographical condition on the distribution of thermal patterns, in particular altitude and the distance from valley bottoms. The results are discussed in order to formulate a general approach for the characterisation of climatic conditions at small scale.

Coral reefs in French Polynesia, just like many others throughout the world, have been subjected to several natural disturbances including 15 cyclones, seven major bleaching events, and several Acanthaster planci outbreaks since the 1980s. In order to document the effects of these perturbations on coral assemblages, we initiated a long-term monitoring program that extended over both local and regional scales. Coral cover was quantified at 20 sites situated on the outer reef slope of 13 islands. The results from the first decade (1992-2002) are analyzed and the adequacy of our approach is discussed in the context of identifying potential indicators of coral reef health. Among 13 islands in French Polynesia, only two were unaffected by natural disturbances. We found important local and regional variation in the impacts of coral bleaching and cyclones, and three major temporal trends were distinguished: 1) 10 sites where coral cover decreased in relation to the occurrence of major disturbances; 2) nine sites where coral cover increased, despite the occurrence of disturbances affecting seven of them; and 3) a site where no significant variation in coral cover was found. The responses to perturbations were different among coral genera: Acropora species were particularly susceptible to bleaching events, whereas physical damages induced by cyclones concerned mainly branching species of Acropora and Pocillopora. Thus, monitoring surveys could be improved by selecting different and complementary indicators (one on the variation in diversity, one estimating changes in the abundance/cover, and one estimating the potential for recovery), by integrating several spatial scales, and by including at least the most informative species. High frequency recordings of environmental parameters (e.g. sea surface temperature) may be also a complementary tools for identifying causal relationships between changes in coral reef community structure and the factors causing the changes.

Eight hundred photosynthesis-irradiance relationships were determined in the shelf waters adjacent to Palmer Station, Antarctica during the spring/summer periods of 1991–94. Biomass specific maximum photosynthetic rate, PBmax, and the light limited photosynthetic efficiency, αB, were poorly correlated to the physical forcing and nutrient regimes at the sampling stations. The two photosynthetic parameters, however, did strongly covary indicating the minimum irradiance required to saturate photosynthesis, Ik, was relatively constant in this highly variable environment. The variability in Ik could partially be attributed to both depth in the water column and time of the year, with the highest values occurring for surface samples during the summer period of peak incident irradiance. Given this and the significant dependence of Pmax on phytoplankton biomass, a simple empirical model for primary productivity was developed. An independent test of the model was performed on data collected in a mesoscale offshore grid and predicted primary production was found to be within 13% of measured values. Although there are limitations to this approach (i.e. exclusion of diel periodicity in photosynthetic response), these results provide relatively robust estimates of daily primary production for the Southern Ocean.

Within the distributional range of a species the number of self-sustaining populations can vary, from one population for panmictic species such as American eel to many populations as observed in Atlantic salmon. This "species-level" characteristic is defined here as "population richness". Aspects of geographic patterns in population richness in the northern Atlantic for Atlantic salmon, American shad, rainbow smelt, Atlantic herring, Atlantic cod, haddock, winter flounder, yellowtail flounder, Atlantic mackerel, and European eel are described. It is concluded that events at the early life-history stages, involving "retention" of the eggs and larvae in relation to particular physical oceanographic features, are involved in the definition of population richness.