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1.
CBE Life Sci Educ ; 22(2): ar25, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37058442

RESUMEN

In-person undergraduate research experiences (UREs) promote students' integration into careers in life science research. In 2020, the COVID-19 pandemic prompted institutions hosting summer URE programs to offer them remotely, raising questions about whether undergraduates who participate in remote research can experience scientific integration and whether they might perceive doing research less favorably (i.e., not beneficial or too costly). To address these questions, we examined indicators of scientific integration and perceptions of the benefits and costs of doing research among students who participated in remote life science URE programs in Summer 2020. We found that students experienced gains in scientific self-efficacy pre- to post-URE, similar to results reported for in-person UREs. We also found that students experienced gains in scientific identity, graduate and career intentions, and perceptions of the benefits of doing research only if they started their remote UREs at lower levels on these variables. Collectively, students did not change in their perceptions of the costs of doing research despite the challenges of working remotely. Yet students who started with low cost perceptions increased in these perceptions. These findings indicate that remote UREs can support students' self-efficacy development, but may otherwise be limited in their potential to promote scientific integration.


Asunto(s)
COVID-19 , Estudiantes , Humanos , Pandemias
2.
Proc Biol Sci ; 290(1990): 20222181, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36629105

RESUMEN

The timing of life events (phenology) can be influenced by climate. Studies from around the world tell us that climate cues and species' responses can vary greatly. If variation in climate effects on phenology is strong within a single ecosystem, climate change could lead to ecological disruption, but detailed data from diverse taxa within a single ecosystem are rare. We collated first sighting and median activity within a high-elevation environment for plants, insects, birds, mammals and an amphibian across 45 years (1975-2020). We related 10 812 phenological events to climate data to determine the relative importance of climate effects on species' phenologies. We demonstrate significant variation in climate-phenology linkage across taxa in a single ecosystem. Both current and prior climate predicted changes in phenology. Taxa responded to some cues similarly, such as snowmelt date and spring temperatures; other cues affected phenology differently. For example, prior summer precipitation had no effect on most plants, delayed first activity of some insects, but advanced activity of the amphibian, some mammals, and birds. Comparing phenological responses of taxa at a single location, we find that important cues often differ among taxa, suggesting that changes to climate may disrupt synchrony of timing among taxa.


Asunto(s)
Ecosistema , Insectos , Animales , Cambio Climático , Estaciones del Año , Temperatura , Aves , Mamíferos
4.
Environ Entomol ; 40(3): 669-78, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22251646

RESUMEN

Competition between scavengers and microorganisms for the nutrients within carrion is well documented. As a significant contributor to food web energetics, carrion serves not only as a food source for scavengers, but also as a reproductive resource for many insects. One example are the burying beetles of the Nicrophorus genus (Coleoptera: Silphidae) whose reproduction is dependent on locating and successfully sequestering vertebrate carrion. Throughout the cooperative preparation of carrion and feeding of the larval offspring, parental beetles coat the carrion with oral and anal secretions known to attenuate the growth of molds and bacteria in the laboratory. We test the hypotheses that Nicrophorus secretions attenuate the growth of naturally occurring microorganisms likely to be found colonizing the carrion resource, and that the active antimicrobial components of the secretions are small antimicrobial peptides (AMPs) similar to those produced by other insects.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Secreciones Corporales/química , Escarabajos/fisiología , Microbiología del Suelo , Animales , Escarabajos/química , Electroforesis en Gel de Poliacrilamida , Femenino , Masculino , Pruebas de Sensibilidad Microbiana , Serina Proteasas
5.
J Exp Biol ; 207(Pt 5): 723-33, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14747404

RESUMEN

This study compares the thermoregulatory ability of three species of burying beetle (Coleoptera: Silphidae: Nicrophorus hybridus, Nicrophorus guttula and Nicrophorus investigator) that vary significantly in body size. It also explores possible mechanisms for temperature regulation in burying beetles, including physiological and behavioral thermoregulatory strategies, and the influence of environmental temperatures on body temperature and activity times. We measured beetle thoracic and abdominal temperatures before and after short (<5 s) flights, and thoracic temperature during sustained, tethered flights and following flight in the field. We calculated two measures of thermoregulatory ability: the slope of post-flight thoracic temperature against ambient air temperature and the slope of post-flight thoracic temperature against operative flight temperature. Thoracic temperatures following flight were significantly higher than abdominal temperatures, and the largest species, N. hybridus, was determined to be the better thermoregulator, with regression slopes closer to zero (0.315-0.370) than N. guttula (0.636-0.771) or N. investigator (0.575-0.610). We also examined the roles that insulation, wing loading, physiological heat transfer, basking and perceived environmental temperature play on temperature regulation and activity times in Nicrophorus: This study shows that body size, morphological features, such as wing loading and insulation, and perceived environmental temperatures affect thermoregulation and activity times in burying beetles.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Escarabajos/fisiología , Ambiente , Animales , Fenómenos Biomecánicos , Constitución Corporal , Escarabajos/anatomía & histología , Vuelo Animal/fisiología , Idaho , Temperatura
6.
Oecologia ; 76(3): 408-415, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28312021

RESUMEN

Researchers have documented microhabitat partitioning among the heteromyid rodents of the deserts of North America that may result from microhabitat specific predation rates; large/bipedal species predominate in the open/risky microhabitat and small/quadrupedal species predominate in the bush/safer microhabitat. Here, we provide direct experimental evidence on the role of predatory risk in affecting the foraging behavior of three species of heteromyid rodents: Arizona pocket mouse (Perognathus amplus; small/quadrupedal), Bailey's pocket mouse (P. baileyi; large/quadrupedal), and Merriam's kangaroo rat (Dipodomys merriami; large/bipedal). Both kangaroo rats and pocket mice are behaviorally flexible and able to adjust their foraging behavior to nightly changes in predatory risk. Under low levels of perceived predatory risk the kangaroo rat foraged relatively more in the open microhabitat than the two pocket mouse species. In response to the presence of barn owls, however, all three species shifted their habitat use towards the bush microhabitat. In response to direct measures of predatory risk, i.e. the actual presence of owls, all three species reduced foraging and left resource patches at higher giving up densities of seeds. In response to indirect indicators of predatory risk, i.e. illumination, there was a tendency for all three species to reduce foraging. The differences in morphology between pocket mice and kangaroo rats do appear to influence their behavioral responses to predatory risk.

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