Body mass and growth rates predict protein intake across animals.

Organisms require dietary macronutrients in specific ratios to maximize performance, and variation in macronutrient requirements plays a central role in niche determination. Although it is well recognized that development and body size can have strong and predictable effects on many aspects of organismal function, we lack a predictive understanding of ontogenetic or scaling effects on macronutrient intake. We determined protein and carbohydrate intake throughout development on lab populations of locusts and compared to late instars of field populations.

Students respond positively to an instructor collecting and sharing aggregated class demographic data from a survey in a high-enrollment physiology course.

The impersonal nature of high-enrollment science courses makes it difficult to build student-instructor relationships, which can negatively impact student learning and engagement, especially for members of marginalized groups. In this study, we explored whether an instructor collecting and sharing aggregated student demographics could positively impact student-instructor relationships. We surveyed students in a high-enrollment physiology course about their perceptions of their instructor ) distributing a demographic survey, and ) sharing aggregated survey results in class.

Vulnerability to climate change increases with trophic level in terrestrial organisms.

The resilience of ecosystem function under global climate change is governed by individual species vulnerabilities and the functional groups they contribute to (e.g. decomposition, primary production, pollination, primary, secondary and tertiary consumption).

Anatomical self-efficacy of undergraduate students improves during a fully online biology course with at-home dissections.

Student enrollments in online college courses have grown steadily over the past decade, and college administrators expect this trend to continue or accelerate. Despite the growing popularity of online education, one major critique in the sciences is that students are not trained in the hands-on skills they may need for the workforce, graduate school, or professional school. For example, the Association of American Medical Colleges has recommended that medical schools evaluate applicants on their motor skills and observation skills, yet many online biology programs do not offer opportunities for students to develop these skills.

Plant carbohydrate content limits performance and lipid accumulation of an outbreaking herbivore.

Locusts are major intermittent threats to food security and the ecological factors determining where and when these occur remain poorly understood. For many herbivores, obtaining adequate protein from plants is a key challenge. We tested how the dietary protein : non-structural carbohydrate ratio (p : c) affects the developmental and physiological performance of 4th-5th instar nymphs of the South American locust, which has recently resurged in Argentina, Bolivia and Paraguay.

Oxygen supply limits the chronic heat tolerance of locusts during the first instar only.

Although scientists know that overheating kills many organisms, they do not agree on the mechanism. According to one theory, referred to as oxygen- and capacity-limitation of thermal tolerance, overheating occurs when a warming organism's demand for oxygen exceeds its supply, reducing the organism's supply of ATP. This model predicts that an organism's heat tolerance should decrease under hypoxia, yet most terrestrial organisms tolerate the same amount of warming across a wide range of oxygen concentrations.

Oxygen Limitation Does Not Drive the Decreasing Heat Tolerance of Grasshoppers during Development.

Thermal physiology changes as organisms grow and develop, but we do not understand what causes these ontogenetic shifts. According to the theory of oxygen- and capacity-limited thermal tolerance, an organism's heat tolerance should change throughout ontogeny as its ability to deliver oxygen varies. As insects grow during an instar, their metabolic demand increases without a proportional increase in the size of tracheae that supply oxygen to the tissues.

Fundamental Flaws with the Fundamental Niche.

For more than 70 years, Hutchinson's concept of the fundamental niche has guided ecological research. Hutchinson envisioned the niche as a multidimensional hypervolume relating the fitness of an organism to relevant environmental factors. Here, we challenge the utility of the concept to modern ecologists, based on its inability to account for environmental variation and phenotypic plasticity.

Thermal acclimation of flies from three populations of Drosophila melanogaster fails to support the seasonality hypothesis.

In seasonal environments, natural selection should favor genotypes that acclimate to slow and predictable changes in temperature. Selective pressure for acclimation should be especially strong for animals that complete many generations per year, because seasonal warming or cooling causes offspring to experience different temperatures than their parents did. Here, we studied variation in acclimation capacity among three populations of Drosophila melanogaster.

The neuroscience of adaptive thermoregulation.

The nervous system acts as a biological thermostat by controlling behaviors that regulate the warming and cooling of animals. We review the structures responsible for thermoregulation in three model species: roundworms (Caenorhabditis elegans), flies (Drosophila melanogaster), and rats (Rattus novegicus). We then consider additional features of the nervous system required to explain adaptive plasticity of the set-point temperature and the precision of thermoregulation.

A positive genetic correlation between hypoxia tolerance and heat tolerance supports a controversial theory of heat stress.

We used quantitative genetics to test a controversial theory of heat stress, in which animals overheat when the demand for oxygen exceeds the supply. This theory, referred to as oxygen- and capacity-limited thermal tolerance, predicts a positive genetic correlation between hypoxia tolerance and heat tolerance. We demonstrate the first genetic correlation of this kind in a model organism, Genotypes more likely to fly under hypoxic stress (12% O) were also more likely to fly under heat stress (39°C).