Genomic Signatures of Divergent Ecological Strategies in a Recent Radiation of Neotropical Wild Cats.

Ecological differentiation among diverging species is an important component of the evolutionary process and can be investigated in rapid and recent radiations. Here, we use whole genome sequences of five species from the genus Leopardus, a recently diversified Neotropical lineage with species bearing distinctive morphological, ecological, and behavioral features, to investigate genome-wide diversity, comparative demographic history and signatures of positive selection. Our results show that divergent ecological strategies are reflected in genomic features, for example a generalist species shows historically larger effective population size and higher heterozygosity than habitat specialists. The demographic history of these cats seems to have been jointly driven by climate fluctuations and habitat specialization, with different ecological adaptations leading to distinct trajectories. Finally, a gene involved in vertebrate retinal neurogenesis (POU4F2) was found to be under positive selection in the margay, a cat with notoriously large eyes that are likely associated with its nocturnal and arboreal specializations.

Evolving spatial conservation prioritization with intraspecific genetic data.

Spatial conservation prioritization (SCP) is a planning framework used to identify new conservation areas on the basis of the spatial distribution of species, ecosystems, and their services to human societies. The ongoing accumulation of intraspecific genetic data on a variety of species offers a way to gain knowledge of intraspecific genetic diversity and to estimate several population characteristics useful in conservation, such as dispersal and population size. Here, we review how intraspecific genetic data have been integrated into SCP and highlight their potential for identifying conservation area networks that represent intraspecific genetic diversity comprehensively and that ensure the long-term persistence of biodiversity in the face of global change.

From Chilean Patagonia to Galapagos, Ecuador: novel insights on blue whale migratory pathways along the Eastern South Pacific.

BACKGROUND: The most traditional scheme for migration among baleen whales comprises yearly migrations between productive waters at high latitude summer feeding grounds and warmer waters at lower latitudes where whales calve and mate, but rarely feed. Evidence indicates, however, that large departures from this scheme exist among populations and individuals. Furthermore, for some populations there is virtually no information on migratory pathways and destinations. Such is the case of Chilean blue whales throughout the Eastern South Pacific; hence, the goal of this study was to assess its migratory behavior. METHODS: Dedicated marine surveys and satellite tagging efforts were undertaken during the austral summer and early autumn on blue whale feeding grounds off Chilean Northern Patagonia (CNP) during 2013, 2015 and 2016. Positional data derived from satellite tags regarding movement patterns and behavior were analyzed using Bayesian switching first-difference correlated random walk models. RESULTS: We instrumented 10 CNP blue whales with satellite transmitters and documented individual variation in departure time, northbound migratory routes and potential wintering grounds. The onset of migration occurred from mid/late austral autumn to well into the austral winter. Blue whales moved in various directions, but ultimately converged toward a general NW movement direction along a wide corridor exceeding 2,000 km. Area-Restricted Search behavior was exhibited within fjords and channels of CNP and also South of Galapagos Archipelago (GA) and northern Peru, but never during migration. Interestingly, dive profiles for one whale that reached GA showed a sharp and consistent increase in depth north of 5°S and extreme deep dives of up to 330 m. DISCUSSION: Information derived from satellite tagged blue whales in this study is the first of its kind off the Eastern Southern Pacific. Our results provide valuable information on their migratory timing, routes and behavior on their northbound migration, particularly regarding the varied migratory plasticity for this particular population. Our results also highlight the first record of two complete migratory paths between CNP and GA and strengthen the hypothesis that GA waters correspond to a potential wintering destination for CNP blue whales. We further hypothesize that this area might be selected because of its biological productivity, which could provide feeding opportunities during the breeding season. Our results suggest that special efforts should be put forward to identify blue whale critical areas and understand key behavioral aspects in order to provide the basis for their conservation on a regional context (i.e., reducing potential ship strike and promote Marine Protected Area (MPA) implementation in Chile, Ecuador and Peru). Indeed, we suggest joint blue whale conservation efforts at the regional level in order to identify and determine potential threats and impacts and, most importantly, implement prospective management actions.

Surveillance after cardiac arrest in patients with Brugada syndrome without an implantable defibrillator: An alarm effect of the previous syncope.

BACKGROUND: Debate regarding the prognosis of asymptomatic patients with Brugada syndrome (BrS) is possibly affected by the selection bias of survivors of sudden cardiac arrest (SCA). We aimed to determine variables influencing surveillance after SCA. METHODS: We analyzed a BrS cohort of 145 patients belonging to 37 families. We compared the clinical data and circumstances surrounding SCA (i.e., place of occurrence and people accompanying the subject) in 10 patients who survived an episode of SCA (Group A) vs. 27 deceased relatives (first or second degree) who suffered sudden cardiac death (SCD; Group B). Information concerning Group B was agreed upon by at least 3 relatives. A sub-analysis was performed considering families carrying a mutation in SCN5A (Group B-Mutant). RESULTS: Syncope was unique in predicting SCA in the BrS cohort. Comparing Groups A vs. B, there were no differences in the mean age at time of SCA/SCD (46.2 [SD 17.1] vs. 39.9 [SD 14.5] years; p=0.271), gender (male 60% vs. 74.1%; p=0.442), prior cardiomyopathy (0%), administration of cardiovascular treatments (anti-hypertensive and lipid-lowering drugs; 20% vs. 14.8%; p=0.653) or conventional cardiovascular risk factors. Environmental circumstances surrounding the SCA/SCD were not significantly different between groups. Prior syncope was more frequent in Group A (80% vs. 3.7%; p<0.001) and unique in predicting surveillance (p<0.001). Group B-Mutant displayed equivalent data. CONCLUSIONS: A previous syncope, as an alarm symptom, might contribute to better surveillance of SCA compared with subjects with SCA as the debut of BrS. The latter might behave as a factor of selection bias.

Time-dependent responses to provocative testing with flecainide in the diagnosis of Brugada syndrome.

BACKGROUND: Time-dependent variability of electrocardiogram (ECG) in patients with Brugada syndrome could affect the interpretation of provocative testing. OBJECTIVE: The aim of this study was to characterize ECG changes during and after flecainide infusion. METHODS: We studied 59 consecutive patients. The ECG was continuously analyzed during the first 30 minutes of provocative testing, and a single ECG was recorded 60 minutes later. We analyzed CYP2D6 and CYP3A5 variants affecting flecainide metabolism and performed blinded measurements at lead II. RESULTS: At baseline, ECG patterns were classified as follows: type II in 31 patients (53%), type III in 15 (25%), and normal ECG in 13 (22%). Because of induction of type I ECG, the percentage of responders progressively increased with longer recording time periods (6.8% in 10 minutes vs 11.9% in 20-30 minutes vs 18.6% in 90 minutes; P < .01). Four patients displayed a late response, which was evidenced 90 minutes after the initiation of provocative testing. QRS width differentially increased between responders and nonresponders (P < .01), with a maximum QRS width of 110 ms during the first 30 minutes being effective for identifying possible late responders (sensitivity 100%; specificity 85.6%; positive predictive value 88%; negative predictive value 100%). The incidence of CYP2D6 variants was lower in late responders than in early or delayed responders (0% vs 75% vs 100%; P = .04), while a homogeneous distribution of CYP3A5*3/*3 was observed in our population. CONCLUSION: Response to flecainide exhibits time-dependent variability of ECG patterns and intervals. Longer periods of ECG recording increase the recognition probability of type I ECG.