Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

Author correction : a global database for metacommunity ecology, integrating species, traits, environment and space

Correction to: Scientific Data https://doi.org/10.1038/s41597-019-0344-7, published online 08 January 202

Species richness in North Atlantic fish: Process concealed by pattern

International audiencePrevious analyses of marine fish species richness based on presence‐absence data have shown changes with latitude and average species size, but little is known about the underlying processes. To elucidate these processes we use metabolic, neutral and descriptive statistical models to analyse how richness responds to maximum species length, fish abundance, temperature, primary production, depth, latitude and longitude, while accounting for differences in species catchability, sampling effort and mesh size

Testing for differences in spatial distributions from individual based data

Spatial distribution is increasingly studied using individual based telemetric methods in lieu of, or supplementing, surveys. Distributions may be in two- or three-dimensions, or in an abstract space such as depth-temperature space. One of the most basic questions one might address when analyzing these data is whether the distributions of two species, populations, genders, age classes, or other units are different. However due to the inherent differences between survey and telemetric approaches, it is difficult for practitioners to find a simple and easily applied approach to answer this question. In contrast to surveys, telemetry collects a large amount of data about a small number of individuals. Methods must therefore account for the random effects of individual variation in a way not otherwise necessary. We will demonstrate, for example, that tests suitable for detecting differences in distributions from survey data can give false positives (type I errors) when faced with telemetry data. This is essentially because the test treats the large number of data points as a very high n, but in fact the small number of individuals makes the n very small. As a solution, we present a test for differences in distribution based on an existing test for survey data based upon randomizing the data at the level of individuals rather than observations

Identification of stock components using morphological markers

This study investigated the development of a quantitative method for distinguishing stock components of Icelandic cod Gadus morhua based on visual examination of morphology. The stock is known to be structured into genetically distinct geographic components (north and south of Iceland) and behavioural types that spawn sympatrically. Differences in morphology were tested between locations, genotypes (a proxy for behaviour) and sexes. Results show morphological markers on the head, fins and body of G. morhua that are correlated with the sex, genotype of the fish at the pantophysin (pan-I) locus and the location at which the fish were caught. Females were found to have relatively deep bodies, and the pan-IBB genotype (associated with deep-water feeding behaviour) have greater gaps between their fins. Overall, morphology is more useful for distinguishing sympatric genotypes but less powerful at identifying genetically distinct geographic sub-populations, perhaps because counter-gradient evolution reduces phenotypic differences even with an underlying genetic cause

Evidence from data storage tags for the presence of lunar and semi-lunar behavioral cycles in spawning Atlantic cod

Understanding the environmental processes determining the timing and success of reproduction is of critical importance to developing effective management strategies of marine fishes. Unfortunately it has proven difficult to comprehensively study the reproductive behavior of broadcast-spawning fishes. The use of electronic data storage tags (DSTs) has the potential to provide insights into the behavior of fishes. These tags allow for data collection over relatively large spatial and temporal scales that can be correlated to predicted environmental conditions and ultimately be used to refine predictions of year class strength. In this paper we present data retrieved from DSTs demonstrating that events putatively identified as Atlantic cod spawning behavior is tied to a lunar cycle with a pronounced semi-lunar cycle within it. Peak activity occurs around the full and new moon with no evidence of relationship with day/night cycles

Testing for differences in spatial distributions from telemetry data

No abstracts are to be cited without prior reference to the author.The spatial distribution of species, and temporal variability thereof, are increasingly being studied using telemetric methods in lieu of, or supplementing, surveys. Such methods include data storage tags and arrays of detectors coupled with transmitter tags. One of the most basic tests one might address when analysing these data is whether the distributions of two species, subunits of a stock, genders, age classes, or a single population at different times, are different. Distributions may be in two or three dimensions, or in an abstract space such as depth–temperature space. Owing to the inherent differences between survey and telemetric approaches, however, it is difficult to find a simple and easily applied approach to answer this question. In contrast to surveys, telemetry collects a large amount of data on a small number of individuals. Methods must therefore account for the random effects of individual variation in a way that was not previously necessary. We will demonstrate, for example, that some tests that are suitable for detecting differences in distributions from survey data give false positives (type I errors) when faced with telemetry data. This is essentially because the test treats the large number of data points as a very high n, but in fact the small number of individuals makes the n very small. We present a test for differences in distribution based on Syrjalaʹs test (1996) and review its possible applications in fishery science. In order to enliven this statistical method talk, we will draw on examples from some exciting topics outside fishery science

Kinetic compartment modeling of [11C]-5-hydroxy-L-tryptophan for positron emission tomography assessment of serotonin synthesis in human brain

The substrate for the second enzymatic step in serotonin synthesis, 5-hydroxy-L-tryptophan, labeled in the beta-position ([11C]-HTP), was used for positron emission tomography (PET) measurements in six healthy human participants, examined on two occasions. One- and two-tissue kinetic compartment modeling of time-radioactivity curves was performed, using arterial, metabolite-corrected [11C]-HTP values as input function. The availability of unchanged tracer in arterial blood plasma was > or = 80% up to 60 minutes after injection, while [11C]-hydroxyindole acetic acid and [11C]-serotonin accounted for the remaining radioactivity, amounting to < or = 16% and < or = 4%, respectively. Compartment modeling was performed for brain stem, putamen, caudate nucleus, anterior cingulate, white matter, and superior occipital, occipitotemporal, and temporal cortices. The average biologic half-life for plasma-to-tissue equilibrium was 7 to 12 minutes, and the volume of distribution was 0.2 to 0.5 microL.mL(-1). In all regions except white matter, the kinetic compartment model that included irreversible [11C]-HTP trapping showed significantly improved model fits with respect to a one-tissue compartment model. The [11C]-HTP trapping rate constant depended on the estimated tissue availability of the serotonin precursor tryptophan, known to reflect serotonin synthesis in healthy individuals, and correlated with serotonin tissue concentration and synthesis rates reported previously in literature. These findings suggest the use of [11C]-HTP PET measurements to investigate serotonin synthesis