Browsing by Author "Boher, Francisca"

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    Does thermal physiology explain the ecological and evolutionary success of invasive species? Lessons from ladybird beetles
    (2018) Boher, Francisca; Jaksic, Fabian M.; Martel, Sebastian I.; Orellana, Maria J.; Bozinovic, Francisco
    Background: Several hypotheses have been proposed to explain invasive species success. Much of the research in this field has been conducted at the ecosystem or community level. Physiological traits are usually ignored, although they may play a role. As invasiveness has been correlated with species range expansion, it has been assumed - but scarcely tested - that species with greater physiological thermotolerances could be more invasive and colonize more habitats.
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    Surgical Implantation of Intra-abdominal Radiotransmitters in Marine Otters (Lontra felina) in Central Chile
    (2008) Soto-Azat, Claudio; Boher, Francisca; Fabry, Mauricio; Pascual, Paulo; Medina-Vogel, Gonzalo
    Six free-ranging marine otters (Lontra felina) were livetrapped on the central coast of Chile and implanted with specially designed radiotransmitters as part of a spatial ecology study. Marine otters frequent the rocky seashore, often squeezing their narrow bodies through cracks and crevices and grooming themselves on the rocks. They are also among the smallest of the otter species, weighing between 3.4 kg and 4.5 kg. For these reasons, the transmitter used was small, rectangular, and flat, measuring 3.5x3.2x1.0 cm. They were implanted using a ventral midline approach to minimize contact between the skin incision and sharp-edged rocks. Surgical incisions healed within 2 wk. The transmitters functioned well, but the duration varied from 62 days to 143 days instead of the 240 days predicted by the manufacturer. All six marine otters reestablished in their home ranges, and survey results suggest they survived well beyond the life of the transmitters.
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    The interplay between thermal tolerance and life history is associated with the biogeography of Drosophila species
    (2010) Boher, Francisca; Godoy-Herrera, Raul; Bozinovic, Francisco
    Background: Physiological tolerances are important determinants of the biogeography of species.
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    The Mean and Variance of Environmental Temperature Interact to Determine Physiological Tolerance and Fitness
    (UNIV CHICAGO PRESS, 2011) Bozinovic, Francisco; Bastias, Daniel A.; Boher, Francisca; Clavijo Baquet, Sabrina; Estay, Sergio A.; Angilletta, Michael J., Jr.
    Global climate change poses one of the greatest threats to biodiversity. Most analyses of the potential biological impacts have focused on changes in mean temperature, but changes in thermal variance will also impact organisms and populations. We assessed the combined effects of the mean and variance of temperature on thermal tolerances, organismal survival, and population growth in Drosophila melanogaster. Because the performance of ectotherms relates nonlinearly to temperature, we predicted that responses to thermal variation (+/-0 degrees or +/-5 degrees C) would depend on the mean temperature (17 degrees or 24 degrees C). Consistent with our prediction, thermal variation enhanced the rate of population growth (r(max)) at a low mean temperature but depressed this rate at a high mean temperature. The interactive effect on fitness occurred despite the fact that flies improved their heat and cold tolerances through acclimation to thermal conditions. Flies exposed to a high mean and a high variance of temperature recovered from heat coma faster and survived heat exposure better than did flies that developed at other conditions. Relatively high survival following heat exposure was associated with low survival following cold exposure. Recovery from chill coma was affected primarily by the mean temperature; flies acclimated to a low mean temperature recovered much faster than did flies acclimated to a high mean temperature. To develop more realistic predictions about the biological impacts of climate change, one must consider the interactions between the mean environmental temperature and the variance of environmental temperature.