Aerospace medicine and biology: A continuing bibliography with indexes (supplement 407)

This bibliography lists 289 reports, articles and other documents announced in the NASA Scientific and Technical Information System during Nov. 1995. Subject coverage includes: aerospace medicine and physiology, life support systems and man/system technology, protective clothing, exobiology and extraterrestrial life, planetary biology, and flight crew behavior and performance

Flexible resource use strategies of a central-place forager experiencing dynamic risk and opportunity

We used data collected from GPS loggers on golden-mantled ground squirrels (Callospermophilus lateralis) to model selection or avoidance of resources in two seasons of seed availability and one season in which no seeds were available. Movement decisions were measured in short-term discrete time intervals using high resolution location data. Selection or avoidance of specific resource features that entail fitness consequences were then assessed using resource selection functions.University of Nevada, Reno, Whittell Forest Graduate Fellowship endowed fundOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Social Ecology and Behavior of Coyotes

Behavioral patterns are subject to natural selection and behavior like any other attributes of an animal, which contributes to individual survival. The chapter summarizes a long-term study of coyotes that was conducted in the Grand Teton National Park, in the northwest comer of Wyoming. There is remarkable agreement in the results stemming from a limited number of field projects concerned with the social behavior and behavioral ecology of coyotes, and some general principles concerning social ecology, scent marking, predatory behavior, time budgeting, and reproductive and care-giving patterns can be developed that are applicable not only to coyotes but to many other carnivores

Macroecology and Sociobiology of Humans and other Mammals

Despite being the most studied species on the planet, ecologists typically do not study humans the same way we study other organisms. My Ph.D. thesis contributes to scientific development in two ways: i) synthesizing our understand of the inter and intraspecific variation in social behavior in an understudied rodent lineage, the caviomorphs, providing a comparative context to understand social evolution in general, and 2) developing a macroecological approach to understand the metabolic trajectory of the human species. Through comparative analysis, chapter 2 synthesizes the available information on the diversity of sociality in the caviomorph rodents, both within and across species. Studies and theory derived from better-studied mammalian taxa establish an integrative and comparative framework from which to examine social systems in caviomorphs. We synthesize the literature to evaluate variation in space use, group size, mating systems, and parental care strategies in caviomorphs in the context of current hypotheses. We highlight unique aspects of caviomorph biology and offer potentially fruitful lines for future research both at the inter and intraspecific levels. We can gain unique insights into the ecological drivers and evolutionary significance of diverse animal societies by studying this diverse taxon. Chapter 3 outlines core ecological principles that should be integral to a science of sustainability: 1) physical conservation laws govern the flows of energy and materials between human systems and the environment, 2) smaller systems are connected by these flows to larger systems in which they are embedded, 3) global constraints ultimately limit flows at smaller scales. Over the past few decades, decreasing per-capita rates of consumption of petroleum, phosphate, agricultural land, fresh water, fish, and wood indicate that the growing human population has surpassed the capacity of the Earth to supply enough of these essential resources to sustain even the current population and level of socioeconomic development. Chapter 4 applies a socio-metabolic perspective of the urban transition coupled with empirical examination of cross-country data spanning decades. It highlights the central role of extra-metabolic energy in global urbanization and the coinciding transition from resource extraction to industrial and service economies. The global urban transition from resource producers in rural areas, to industrial and service employment in urban systems is fuelled by supplementing extra-metabolic energy in the form of fossil fuels for decreasing human and animal labor. Collectively, I hope this work demonstrates the utility of comparative analysis and synthesis in understanding the evolutionary ecology of sociality and the power of a macroecological approach in understanding the metabolic ecology and trajectory of the human species

The Glass is Half-Full: Overestimating the Quality of a Novel Environment is Advantageous

According to optimal foraging theory, foraging decisions are based on the forager's current estimate of the quality of its environment. However, in a novel environment, a forager does not possess information regarding the quality of the environment, and may make a decision based on a biased estimate. We show, using a simple simulation model, that when facing uncertainty in heterogeneous environments it is better to overestimate the quality of the environment (to be an “optimist”) than underestimate it, as optimistic animals learn the true value of the environment faster due to higher exploration rate. Moreover, we show that when the animal has the capacity to remember the location and quality of resource patches, having a positively biased estimate of the environment leads to higher fitness gains than having an unbiased estimate, due to the benefits of exploration. Our study demonstrates how a simple model of foraging with incomplete information, derived directly from optimal foraging theory, can produce well documented complex space-use patterns of exploring animals

Parasitism in viviparous vertebrates: an overview

"Viviparity is a reproductive mode that has evolved independently in different taxa where offspring develop inside females to ensure gestation. Offspring are provided with a food supply in the egg or through specialized tissues that ensure their development thanks to the specific exchange of nutrients and other components. However, environmental challenges such as parasitism and disease can be a force that limit the host's resources causing physiological, morphological, and behavioural changes that represent an additional cost for both the pregnant female and her offspring. This includes the future reproductive investment on females, sex rate in their offspring, lactation investment in mammals, alterations of birth intervals, the current reproduvtive investment, variation between environments, the activity of the immune system facing immunological challenges, as well as additional factors that can affect the interaction between viviparous females and parasites. Parasites could be a significant mediator of this reproductive mode: parasitized females change their investment in survival and reproduction based on their life history, the environmental factors they are exposed to, and the diversity of parasites they encounter"

Anthropogenic influences on the time budgets of urban vervet monkeys.

Continuing urban developments are ecologically changing many landscapes. A greater understanding of how wildlife adapt behaviorally to these changes is necessary to inform management decisions. Time is a valuable resource to wildlife and a reflection of ecological pressures on the behavioral repertoire of an animal. Data on urban vervet monkey, Chlorocebus pygerythrus, time budgets are generally limited and dated. We aimed to investigate the effect of anthropogenic influences, both human food consumption (positive) and human-monkey conflict (negative) on the time budgets of vervet monkeys in an urban landscape. We collected 20 min. focal animal observations and used generalized linear mixed models to assess the variation in time budget between five urban vervet monkey troops differing in anthropogenic contact over one year. We recorded anthropogenic interactions ad lib. as positive and negative. Our results showed seasonal influences across all behaviors. Furthermore, anthropogenic disturbance influenced all aspects of time budget to some degree. We found a positive interaction effect between positive and negative human incidents on foraging, and a negative interaction effect on movement and social behavior. Overall, vervet monkeys exhibited behavioral flexibility in the urban landscape. We suggest a complex association of costs and benefits to urban living

Relationships among parasites, physiological stress and personality in the interactions between invasive alien and native species

The thesis explored the interactions between Invasive Alien Species (IAS) and native species in the light of potential effects of parasitic infections, physiological stress and personality on individual fitness (reproductive success/investment). In particular, this study investigated the interspecific competition between the North American invasive Eastern grey squirrel (Sciurus carolinensis) and the native Eurasian red squirrel (Sciurus vulgaris), describing techniques and methods that successively have been applied to evaluate the relationships between personality, stress and parasite load. Chapter 1 reported the validation of a method to measure physiological stress in Eurasian red squirrel; Chapter 2 showed the application of this method to evaluate physiological stress in the native species in co-occurrence with Eastern grey squirrels. Chapter 3 presented estimates of personality of individual squirrels using indirect indices and their validation through correlation with direct personality measurements from arena tests. Chapter 4 examined the methods previously identified to explore the relationship between personality and parasite infections in Eastern grey squirrels. Reproductive success/investment could be influenced by the cumulative effect of factors analysed above. Chapter 5 presented the application of a staining technique of uterine scars count to estimate fecundity in invasive squirrel populations. Finally, Chapter 6 examined the relationships between parasite load, physiological stress, reproductive success and/or investment and the potential mediatory role of personality

Variational Autoencoder Based Estimation Of Distribution Algorithms And Applications To Individual Based Ecosystem Modeling Using EcoSim

Individual based modeling provides a bottom up approach wherein interactions give rise to high-level phenomena in patterns equivalent to those found in nature. This method generates an immense amount of data through artificial simulation and can be made tractable by machine learning where multidimensional data is optimized and transformed. Using individual based modeling platform known as EcoSim, we modeled the abilities of elitist sexual selection and communication of fear. Data received from these experiments was reduced in dimension through use of a novel algorithm proposed by us: Variational Autoencoder based Estimation of Distribution Algorithms with Population Queue and Adaptive Variance Scaling (VAE-EDA-Q AVS). We constructed a novel Estimation of Distribution Algorithm (EDA) by extending generative models known as variational autoencoders (VAE). VAE-EDA-Q, proposed by us, smooths the data generation process using an iteratively updated queue (Q) of populations. Adaptive Variance Scaling (AVS) dynamically updates the variance at which models are sampled based on fitness. The combination of VAE-EDA-Q with AVS demonstrates high computational efficiency and requires few fitness evaluations. We extended VAE-EDA-Q AVS to act as a feature reducing wrapper method in conjunction with C4.5 Decision trees to reduce the dimensionality of data. The relationship between sexual selection, random selection, and speciation is a contested topic. Supporting evidence suggests sexual selection to drive speciation. Opposing evidence contends either a negative or absence of correlation to exist. We utilized EcoSim to model elitist and random mate selection. Our results demonstrated a significantly lower speciation rate, a significantly lower extinction rate, and a significantly higher turnover rate for sexual selection groups. Species diversification was found to display no significant difference. The relationship between communication and foraging behavior similarly features opposing hypotheses in claim of both increases and decreases of foraging behavior in response to alarm communication. Through modeling with EcoSim, we found alarm communication to decrease foraging activity in most cases, yet gradually increase foraging activity in some other cases. Furthermore, we found both outcomes resulting from alarm communication to increase fitness as compared to non-communication