Carotenoid Supplementation Enhances Reproductive Success in Captive Strawberry Poison Frogs (Oophaga Pumilio)

Amphibians are currently experiencing the most severe declines in biodiversity of any vertebrate, and their requirements for successful reproduction are poorly understood. Here, we show that supplementing the diet of prey items (fruit flies) with carotenoids has strong positive effects on the reproduction of captive strawberry poison frogs (Oophaga pumilio), substantially increasing the number of metamorphs produced by pairs. This improved reproduction most likely arose via increases in the quality of both the fertilized eggs from which tadpoles develop and trophic eggs that are fed to tadpoles by mothers. Frogs in this colony had previously been diagnosed with a Vitamin A deficiency, and this supplementation may have resolved this issue. These results support growing evidence of the importance of carotenoids in vertebrate reproduction and highlight the nuanced ways in which nutrition constrains captive populations. Zoo Biol. XX:XX-XX, 2013

The Death Throes of a Stripped Massive Star: An Eruptive Mass-Loss History Encoded in Pre-Explosion Emission, a Rapidly Rising Luminous Transient, and a Broad-Lined Ic Supernova SN2018gep

We present detailed observations of ZTF18abukavn (SN2018gep), discovered in high-cadence data from the Zwicky Transient Facility as a rapidly rising (1.3 mag/hr) and luminous (M_(g,peak) = −20 mag) transient. It is spectroscopically classified as a broad-lined stripped-envelope supernova (Ic-BL SN). The rapid rise to peak bolometric luminosity and blue colors at peak (t_(rise)∼0.5-3 days, L_(bol)≳3×10^(44) erg sec^(−1), g−r = −0.3) resemble the high-redshift Ic-BL iPTF16asu, as well as several other unclassified fast transients. The early discovery of SN2018gep (within an hour of shock breakout) enabled an intensive spectroscopic campaign, including the highest-temperature (T_(eff) ≳ 40,000K) spectra of a stripped-envelope SN. A retrospective search revealed luminous (M_g ∼ M_r ≈ −14mag) emission in the days to weeks before explosion, the first definitive detection of precursor emission for a Ic-BL. We find a limit on the isotropic gamma-ray energy release E_(γ,iso) < 4.9×10^(48) erg, a limit on X-ray emission L_X < 10^(40) erg sec^(−1), and a limit on radio emission νL_ν ≲ 10^(37) erg sec^(−1). Taken together, we find that the data are best explained by shock breakout in a massive shell of dense circumstellar material (0.02 M⊙) at large radii (3×10^(14)cm) that was ejected in eruptive pre-explosion mass-loss episodes

GROWTH on GW190425: Searching thousands of square degrees to identify an optical or infrared counterpart to a binary neutron star merger with the Zwicky Transient Facility and Palomar Gattini IR

The beginning of the third observing run by the network of gravitational-wave detectors has brought the discovery of many compact binary coalescences. Prompted by the detection of the first binary neutron star merger in this run (GW190425 / LIGO/Virgo S190425z), we performed a dedicated follow-up campaign with the Zwicky Transient Facility (ZTF) and Palomar Gattini-IR telescopes. As it was a single gravitational-wave detector discovery, the initial skymap spanned most of the sky observable from Palomar Observatory, the site of both instruments. Covering 8000 deg$^2$ of the inner 99\% of the initial skymap over the next two nights, corresponding to an integrated probability of 46\%, the ZTF system achieved a depth of $\approx$\,21 $m_\textrm{AB}$ in $g$- and $r$-bands. Palomar Gattini-IR covered a total of 2200 square degrees in $J$-band to a depth of 15.5\,mag, including 32\% of the integrated probability based on the initial sky map. However, the revised skymap issued the following day reduced these numbers to 21\% for the Zwicky Transient Facility and 19\% for Palomar Gattini-IR. Out of the 338,646 ZTF transient "alerts" over the first two nights of observations, we narrowed this list to 15 candidate counterparts. Two candidates, ZTF19aarykkb and ZTF19aarzaod were particularly compelling given that their location, distance, and age were consistent with the gravitational-wave event, and their early optical lightcurves were photometrically consistent with that of kilonovae. These two candidates were spectroscopically classified as young core-collapse supernovae. The remaining candidates were photometrically or spectroscopically ruled-out as supernovae. Palomar Gattini-IR identified one fast evolving infrared transient after the merger, PGIR19bn, which was later spectroscopically classified as an M-dwarf flare. [abridged

The Death Throes of a Stripped Massive Star: An Eruptive Mass-Loss History Encoded in Pre-Explosion Emission, a Rapidly Rising Luminous Transient, and a Broad-Lined Ic Supernova SN2018gep

We present detailed observations of ZTF18abukavn (SN2018gep), discovered in high-cadence data from the Zwicky Transient Facility as a rapidly rising (1.3 mag/hr) and luminous (M_(g,peak) = −20 mag) transient. It is spectroscopically classified as a broad-lined stripped-envelope supernova (Ic-BL SN). The rapid rise to peak bolometric luminosity and blue colors at peak (t_(rise)∼0.5-3 days, L_(bol)≳3×10^(44) erg sec^(−1), g−r = −0.3) resemble the high-redshift Ic-BL iPTF16asu, as well as several other unclassified fast transients. The early discovery of SN2018gep (within an hour of shock breakout) enabled an intensive spectroscopic campaign, including the highest-temperature (T_(eff) ≳ 40,000K) spectra of a stripped-envelope SN. A retrospective search revealed luminous (M_g ∼ M_r ≈ −14mag) emission in the days to weeks before explosion, the first definitive detection of precursor emission for a Ic-BL. We find a limit on the isotropic gamma-ray energy release E_(γ,iso) < 4.9×10^(48) erg, a limit on X-ray emission L_X < 10^(40) erg sec^(−1), and a limit on radio emission νL_ν ≲ 10^(37) erg sec^(−1). Taken together, we find that the data are best explained by shock breakout in a massive shell of dense circumstellar material (0.02 M⊙) at large radii (3×10^(14)cm) that was ejected in eruptive pre-explosion mass-loss episodes

GROWTH on S190425z: Searching Thousands of Square Degrees to Identify an Optical or Infrared Counterpart to a Binary Neutron Star Merger with the Zwicky Transient Facility and Palomar Gattini-IR

The third observing run by LVC has brought the discovery of many compact binary coalescences. Following the detection of the first binary neutron star merger in this run (LIGO/Virgo S190425z), we performed a dedicated follow-up campaign with the Zwicky Transient Facility (ZTF) and Palomar Gattini-IR telescopes. The initial skymap of this single-detector gravitational wave (GW) trigger spanned most of the sky observable from Palomar Observatory. Covering 8000 deg2 of the initial skymap over the next two nights, corresponding to 46% integrated probability, ZTF system achieved a depth of ≈21 m AB in g- and r-bands. Palomar Gattini-IR covered 2200 square degrees in J-band to a depth of 15.5 mag, including 32% integrated probability based on the initial skymap. The revised skymap issued the following day reduced these numbers to 21% for the ZTF and 19% for Palomar Gattini-IR. We narrowed 338,646 ZTF transient "alerts" over the first two nights of observations to 15 candidate counterparts. Two candidates, ZTF19aarykkb and ZTF19aarzaod, were particularly compelling given that their location, distance, and age were consistent with the GW event, and their early optical light curves were photometrically consistent with that of kilonovae. These two candidates were spectroscopically classified as young core-collapse supernovae. The remaining candidates were ruled out as supernovae. Palomar Gattini-IR did not identify any viable candidates with multiple detections only after merger time. We demonstrate that even with single-detector GW events localized to thousands of square degrees, systematic kilonova discovery is feasible

Early Ultraviolet Observations of Type IIn Supernovae Constrain the Asphericity of Their Circumstellar Material

We present a survey of the early evolution of 12 Type IIn supernovae (SNe IIn) at ultraviolet and visible light wavelengths. We use this survey to constrain the geometry of the circumstellar material (CSM) surrounding SN IIn explosions, which may shed light on their progenitor diversity. In order to distinguish between aspherical and spherical CSM, we estimate the blackbody radius temporal evolution of the SNe IIn of our sample, following the method introduced by Soumagnac et al. We find that higher-luminosity objects tend to show evidence for aspherical CSM. Depending on whether this correlation is due to physical reasons or to some selection bias, we derive a lower limit between 35% and 66% for the fraction of SNe IIn showing evidence for aspherical CSM. This result suggests that asphericity of the CSM surrounding SNe IIn is common—consistent with data from resolved images of stars undergoing considerable mass loss. It should be taken into account for more realistic modeling of these events

Larval aggression is independent of food limitation in nurseries of a poison frog

Aggression between nurserymates is common in animals and often hypothesized to result from proximate resource limita- tion. In numerous terrestrial frogs, larvae develop in phytotelmata, tiny water bodies where resources are scarce and competition, aggression, and cannibalism are all common between individuals sharing these nurseries. In some species, mothers provision phytotelm-bound young with trophic eggs, a strategy that compensates for low nutrient availability and could allow mothers to reduce costly aggression and cannibal- ism among nurserymates. We tested this hypothesis using strawberry poison frog (Oophaga pumilio) tadpoles, staging secondary depositions in arenas occupied by residents that had either been food deprived or fed ad libitum. Resident tadpoles were nearly all aggressive and most killed intruders, but aggression was unrelated to resident food deprivation. Unlike most related frogs studied, O. pumilio residents did not cannibalize their victims. This result supports the hypothesis that proximate food limitation and aggression can be independent.Louisiana Board/[LEQSF-EPS(2013)-PFUND-332]//Estados UnidosNational Science foundation/[1146370]/NFS/Estados UnidosUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias de la Salud::Instituto Clodomiro Picado (ICP