Immunological and physiological responses to predation risk and sublethal concentrations of chlorothalonil and β-endosulfan in Lithobates taylori (Anura: Ranidae) tadpoles.

Pesticide exposure and its interaction with other natural stressors can play a role in amphibian population declines because disruptions in stress hormone regulatory mechanisms may inhibit immune responses during metamorphosis. Here, we determined the interactive effects of predation risk and sublethal concentration of two pesticides on immunological and physiological responses in tadpoles of the tropical frog Lithobates taylori. Using mesocosms, we used chronic exposure to three levels of chlorothalonil and β-endosulfan in the presence or absence of Odonate larvae.

Efficient coding of natural images in the mouse visual cortex.

How the activity of neurons gives rise to natural vision remains a matter of intense investigation. The mid-level visual areas along the ventral stream are selective to a common class of natural images-textures-but a circuit-level understanding of this selectivity and its link to perception remains unclear. We addressed these questions in mice, first showing that they can perceptually discriminate between textures and statistically simpler spectrally matched stimuli, and between texture types.

Meso-Py: Dual Brain Cortical Calcium Imaging in Mice during Head-Fixed Social Stimulus Presentation.

We present a cost-effective, compact foot-print, and open-source Raspberry Pi-based widefield imaging system. The compact nature allows the system to be used for close-proximity dual-brain cortical mesoscale functional-imaging to simultaneously observe activity in two head-fixed animals in a staged social touch-like interaction. We provide all schematics, code, and protocols for a rail system where head-fixed mice are brought together to a distance where the macrovibrissae of each mouse make contact.

Two new species of semiaquatic Anolis (Squamata: Dactyloidae) from Costa Rica.

We describe two new species of Draconura-clade semiaquatic anoles from the central Pacific versant of Costa Rica. The two new species are similar to Anolis aquaticus in external appearance and ecology but differ from this species in male dewlap coloration and scalation. Anolis robinsoni sp.

Recent findings of Isthmohyla pictipes (Anura: Hylidae) in Costa Rica: variation and implications for conservation.

We report recent findings of Isthmohyla pictipes (Cope, 1875) in the Cordillera de Talamanca, Costa Rica, roughly two decades after it was last registered. We provide notes on microhabitat use, color variation, external morphology of adults and larvae, and geographic variation, and discuss some taxonomic characters employed to differentiate I. pictipes from I.

Automated task training and longitudinal monitoring of mouse mesoscale cortical circuits using home cages.

We report improved automated open-source methodology for head-fixed mesoscale cortical imaging and/or behavioral training of home cage mice using Raspberry Pi-based hardware. Staged partial and probabilistic restraint allows mice to adjust to self-initiated headfixation over 3 weeks' time with ~50% participation rate. We support a cue-based behavioral licking task monitored by a capacitive touch-sensor water spout.

Physiological Signature of Memory Age in the Prefrontal-Hippocampal Circuit.

The long-term storage of episodic memory requires communication between prefrontal cortex and hippocampus. However, how consolidation alters dynamic interactions between these regions during subsequent recall remains unexplored. Here we perform simultaneous electrophysiological recordings from anterior cingulate cortex (ACC) and hippocampal CA1 in mice during recall of recent and remote contextual fear memory.

Batrachochytrium dendrobatidis infection in amphibians predates first known epizootic in Costa Rica.

Emerging infectious diseases are a growing threat to biodiversity worldwide. Outbreaks of the infectious disease chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), are implicated in the decline and extinction of numerous amphibian species. In Costa Rica, a major decline event occurred in 1987, more than two decades before this pathogen was discovered.

Toxicity and Alkaloid Profiling of the Skin of the Golfo Dulcean Poison Frog Phyllobates vittatus (Dendrobatidae).

Frogs in the genus Phyllobates are known for the presence of batrachotoxin, a highly toxic alkaloid, in their skin. Nevertheless, Phyllobates frogs from Costa Rica and Panama (P. lugubris and P.

Individualized tracking of self-directed motor learning in group-housed mice performing a skilled lever positioning task in the home cage.

Skilled forelimb function in mice is traditionally studied through behavioral paradigms that require extensive training by investigators and are limited by the number of trials individual animals are able to perform within a supervised session. We developed a skilled lever positioning task that mice can perform within their home cage. The task requires mice to use their forelimb to precisely hold a lever mounted on a rotary encoder within a rewarded position to dispense a water reward.

An Automated Home-Cage System to Assess Learning and Performance of a Skilled Motor Task in a Mouse Model of Huntington's Disease.

Behavioral testing is a critical step in assessing the validity of rodent models of neurodegenerative disease, as well as evaluating the efficacy of pharmacological interventions. In models of Huntington's disease (HD), a gradual progression of impairments is observed across ages, increasing the need for sensitive, high-throughput and longitudinal assessments. Recently, a number of automated systems have been developed to perform behavioral profiling of animals within their own home-cage, allowing for 24-h monitoring and minimizing experimenter interaction.

Mesoscale brain explorer, a flexible python-based image analysis and visualization tool.

Imaging of mesoscale brain activity is used to map interactions between brain regions. This work has benefited from the pioneering studies of Grinvald et al., who employed optical methods to image brain function by exploiting the properties of intrinsic optical signals and small molecule voltage-sensitive dyes.

Shared Epizoic Taxa and Differences in Diatom Community Structure Between Green Turtles (Chelonia mydas) from Distant Habitats.

The first reports of diatoms growing on marine mammals date back to the early 1900s. However, only recently has direct evidence been provided for similar associations between diatoms and sea turtles. We present a comparison of diatom communities inhabiting carapaces of green turtles Chelonia mydas sampled at two remote sites located within the Indian (Iran) and Atlantic (Costa Rica) Ocean basins.

Cost effective raspberry pi-based radio frequency identification tagging of mice suitable for automated in vivo imaging.

Background: Automation of animal experimentation improves consistency, reduces potential for error while decreasing animal stress and increasing well-being. Radio frequency identification (RFID) tagging can identify individual mice in group housing environments enabling animal-specific tracking of physiological parameters.

New Method: We describe a simple protocol to radio frequency identification (RFID) tag and detect mice.

High-throughput automated home-cage mesoscopic functional imaging of mouse cortex.

Mouse head-fixed behaviour coupled with functional imaging has become a powerful technique in rodent systems neuroscience. However, training mice can be time consuming and is potentially stressful for animals. Here we report a fully automated, open source, self-initiated head-fixation system for mesoscopic functional imaging in mice.

Diatoms and Other Epibionts Associated with Olive Ridley (Lepidochelys olivacea) Sea Turtles from the Pacific Coast of Costa Rica.

Although the sea turtles have long been familiar and even iconic to marine biologists, many aspects of their ecology remain unaddressed. The present study is the first of the epizoic diatom community covering the olive ridley turtle's (Lepidochelys olivacea) carapace and the first describing diatoms living on sea turtles in general, with the primary objective of providing detailed information on turtle epibiotic associations. Samples of turtle carapace including the associated diatom biofilm and epizoic macro-fauna were collected from Ostional beach (9° 59´ 23.

Individualistic population responses of five frog species in two changing tropical environments over time.

Roughly 40% of amphibian species are in decline with habitat loss, disease, and climate change being the most cited threats. Heterogeneity of extrinsic (e.g.

Not everything is black and white: color and behavioral variation reveal a continuum between cryptic and aposematic strategies in a polymorphic poison frog.

Aposematism and crypsis are often viewed as two extremes of a continuum of visual conspicuousness to predators. Theory predicts that behavioral and coloration conspicuousness should vary in tandem along the conspicuousness spectrum for antipredator strategies to be effective. Here we used visual modeling of contrast and behavioral observations to examine the conspicuousness of four populations of the granular poison frog, Oophaga granulifera, which exhibits almost continuous variation in dorsal color.

The impact of conservation on the status of the world's vertebrates.

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these.

An enigmatic frog of the genus Atelopus (Family Bufonidae) from Parque Nacional Chirripó, Cordillera de Talamanca, Costa Rica.

A distinctive new species of Atelopus is described from Parque Nacional Chirrip6 Grande, Cordillera de Talamanca (3,400-3,500 m). It closely resembles populations of the Atelopus ignescens complex from the Andes of northern Ecuador and southern Colombia. It differs most significantly from these frogs in the pattern of spiculae and coni development on the throat, chest, hands and feet.

Diversity, natural history and conservation of amphibians and reptiles from the San Vito Region, southwestern Costa Rica.

We present an inventory of the amphibians and reptiles of the San Vito de Coto Brus region, including the Las Cruces Biological Station, in southern Costa Rica, which is the result of a survey of the herpetofauna occurring in mountain forest fragments, pastures, coffee plantations, and other disturbed areas. We found 67 species, included 26 species of amphibians and of 41 of reptiles. We describe the distribution patterns of the community on the basis of the life zones, elevation, fragmentation, and degree of anthropogenic impact.