Late Pleistocene megafauna extinction leads to missing pieces of ecological space in a North American mammal community

The conservation status of large-bodied mammals is dire. Their decline has serious consequences because they have unique ecological roles not replicated by smaller-bodied animals. Here, we use the fossil record of the megafauna extinction at the terminal Pleistocene to explore the consequences of past biodiversity loss. We characterize the isotopic and body-size niche of a mammal community in Texas before and after the event to assess the influence on the ecology and ecological interactions of surviving species (\u3e1 kg). Preextinction, a variety of C4 grazers, C3 browsers, and mixed feeders existed, similar to modern African savannas, with likely specialization among the two sabertooth species for juvenile grazers. Postextinction, body size and isotopic niche space were lost, and the δ13C and δ15N values of some survivors shifted. We see mesocarnivore release within the Felidae: the jaguar, now an apex carnivore, moved into the specialized isotopic niche previously occupied by extinct cats. Puma, previously absent, became common and lynx shifted toward consuming more C4-based resources. Lagomorphs were the only herbivores to shift toward C4 resources. Body size changes from the Pleistocene to Holocene were species-specific, with some animals (deer, hare) becoming significantly larger and others smaller (bison, rabbits) or exhibiting no change to climate shifts or biodiversity loss. Overall, the Holocene body-size-isotopic niche was drastically reduced and considerable ecological complexity lost. We conclude biodiversity loss led to reorganization of survivors and many “missing pieces” within our community; without intervention, the loss of Earth’s remaining ecosystems that support megafauna will likely suffer the same fate

An ultrahot Neptune in the Neptune desert

About 1 out of 200 Sun-like stars has a planet with an orbital period shorter than one day: an ultrashort-period planet. All of the previously known ultrashort-period planets are either hot Jupiters, with sizes above 10 Earth radii (R⊕), or apparently rocky planets smaller than 2 R⊕. Such lack of planets of intermediate size (the ‘hot Neptune desert’) has been interpreted as the inability of low-mass planets to retain any hydrogen/helium (H/He) envelope in the face of strong stellar irradiation. Here we report the discovery of an ultrashort-period planet with a radius of 4.6 R⊕ and a mass of 29 M⊕, firmly in the hot Neptune desert. Data from the Transiting Exoplanet Survey Satellite revealed transits of the bright Sun-like star LTT 9779 every 0.79 days. The planet’s mean density is similar to that of Neptune, and according to thermal evolution models, it has a H/He-rich envelope constituting 9.0^(+2.7)_(−2.9)% of the total mass. With an equilibrium temperature around 2,000 K, it is unclear how this ‘ultrahot Neptune’ managed to retain such an envelope. Follow-up observations of the planet’s atmosphere to better understand its origin and physical nature will be facilitated by the star’s brightness (V_(mag) = 9.8)

Registros notables de la guacamaya verde (ara militaris) en el norte del estado de Guerrero, México

We report for first time the presence of military macaw (Ara militaris) in the north region of Guerrero State. The region is not considered in any conservation instrument, and this report highlights the urgent need for conservation planning in the state

Estado nutricio de vitamina A en preescolares con padecimientos oculares Nutritional status of vitamin A in preschoolers with ocular diseases

El propósito del estudio fue evaluar el estado nutricio de vitamina A en preescolares con padecimientos oculares que acuden al Hospital Civil de Guadalajara. En estudio transversal analítico se incluyeron por conveniencia 100 sujetos (24-71 meses) con padecimiento ocular. El consumo de vitamina A (VA), energía y macro nutrimentos se estimó con una encuesta dietética de recordatorio de 24 horas (EDR-24h). Mediante cromatografía líquida de alta presión (HPLC) se determinó la concentración sérica de retinol y se realizó una citología de impresión conjuntival (CIC) por un patólogo entrenado en la técnica. Se estimaron los índices talla/edad y peso/talla (Puntaje z) y se utilizaron las pruebas de ANOVA, U de Mann Whitney y de correlación de Spearman. Fueron niñas 44,1% y varones 55.9%. Los padecimientos oculares más frecuentes fueron: estrabismo (41,9%), conjuntivitis (19,4%) y padecimientos congénitos (17,2%). Según la EDR-24 h el consumo de vitamina A fue de 374 µg/día ± 706; la concentración de Retinol sérico 30 µg/dL ± 7,6 y CIC fue normal en 75,6%. Sólo 3.2% a 3,5% presentaron deficiencia de VA (concentración de retinol y CIC). No hubo asociación entre padecimientos oculares y deficiencia de VA. Hubo correlación positiva entre consumo de vitamina A e índice peso/talla (r = 0,244). En conclusión, la mayoría de los preescolares cubrió la ingestión recomendada de vitamina A, la deficiencia de esta vitamina fue baja y no se asoció a padecimientos oculares.SUMMARY The purpose was to evaluate the nutritional status of vitamin A in preschool children with ocular diseases attending to the Hospital Civil of Guadalajara. In a cross sectional design 100 preschool children between 24 and 71 mo of age with ocular diseases were included. Vitamin A intake was evaluated by 24 h dietetic recall, plasma Retinol concentration by high pressure liquid chromatography (HPLC); and, conjunctiva impression cytology (CIC) was carried out by a trained pathologist. ANOVA and U Mann Whitney tests, and also Spearman correlations were estimated. There were 44.1% females and 55,9% males. Strabismus was the most common disease (41,9%), conjunctivitis (19,4%), and congenital diseases (17,2%). The mean intake of Vitamin A was 374 µg/d ± 706 and the serum concentration of retinol was of 30 µg/dL ± 7,6; CIC was normal in 75,6%. The percentage of vitamin A deficiency was 3,2% according to the serum concentration of Retinol and 3,5% to the CIC criteria. It was not association between the nutritional status of vitamin A and ocular diseases. A positive correlation between vitamin A intake and weight/height index (r = 0,244) was found. In conclusion, most preschool children covered the dietary reference intake recommendation of vitamin A; deficiency of this vitamin was lower and, it was not associated to ocular diseases

Estado nutricio de vitamina A en preescolares con padecimientos oculares

El propósito del estudio fue evaluar el estado nutricio de vitamina A en preescolares con padecimientos oculares que acuden al Hospital Civil de Guadalajara. En estudio transversal analítico se incluyeron por conveniencia 100 sujetos (24-71 meses) con padecimiento ocular. El consumo de vitamina A (VA), energía y macro nutrimentos se estimó con una encuesta dietética de recordatorio de 24 horas (EDR-24h). Mediante cromatografía líquida de alta presión (HPLC) se determinó la concentración sérica de retinol y se realizó una citología de impresión conjuntival (CIC) por un patólogo entrenado en la técnica. Se estimaron los índices talla/edad y peso/talla (Puntaje z) y se utilizaron las pruebas de ANOVA, U de Mann Whitney y de correlación de Spearman. Fueron niñas 44,1% y varones 55.9%. Los padecimientos oculares más frecuentes fueron: estrabismo (41,9%), conjuntivitis (19,4%) y padecimientos congénitos (17,2%). Según la EDR-24 h el consumo de vitamina A fue de 374 µg/día ± 706; la concentración de Retinol sérico 30 µg/dL ± 7,6 y CIC fue normal en 75,6%. Sólo 3.2% a 3,5% presentaron deficiencia de VA (concentración de retinol y CIC). No hubo asociación entre padecimientos oculares y deficiencia de VA. Hubo correlación positiva entre consumo de vitamina A e índice peso/talla (r = 0,244). En conclusión, la mayoría de los preescolares cubrió la ingestión recomendada de vitamina A, la deficiencia de esta vitamina fue baja y no se asoció a padecimientos oculares

Industrial water treatment

Dispersal knowledge is essential for conservation management, and demand is growing. But are we accumulating dispersal knowledge at a pace that can meet the demand? To answer this question we tested for changes in dispersal data collection and use over time. Our systematic review of 655 conservation-related publications compared five topics: climate change, habitat restoration, population viability analysis, land planning (systematic conservation planning) and invasive species. We analysed temporal changes in the: (i) questions asked by dispersal-related research; (ii) methods used to study dispersal; (iii) the quality of dispersal data; (iv) extent that dispersal knowledge is lacking, and; (v) likely consequences of limited dispersal knowledge. Research questions have changed little over time; the same problems examined in the 1990s are still being addressed. The most common methods used to study dispersal were occupancy data, expert opinion and modelling, which often provided indirect, low quality information about dispersal. Although use of genetics for estimating dispersal has increased, new ecological and genetic methods for measuring dispersal are not yet widely adopted. Almost half of the papers identified knowledge gaps related to dispersal. Limited dispersal knowledge often made it impossible to discover ecological processes or compromised conservation outcomes. The quality of dispersal data used in climate change research has increased since the 1990s. In comparison, restoration ecology inadequately addresses large-scale process, whilst the gap between knowledge accumulation and growth in applications may be increasing in land planning. To overcome apparent stagnation in collection and use of dispersal knowledge, researchers need to: (i) improve the quality of available data using new approaches; (ii) understand the complementarities of different methods and; (iii) define the value of different kinds of dispersal information for supporting management decisions. Ambitious, multi-disciplinary research programs studying many species are critical for advancing dispersal research

Number of papers reviewed in each topic and time period.

<p>Time periods include Old (1990–2000) and New (2010–2012), with dates of each time period indicated (number of papers identified using search terms and number we reviewed in parenthesis). Search terms for topics are in addition to the search terms for dispersal (see text).</p