James S. Waters

Providence College | PC · Department of Biology

In social insect colonies, individuals are physically independent but functionally integrated by interaction networks which provide a foundation for communication and drive the emergence of collective behaviors, including nest architecture, division of labor, and potentially also the social regulation of metabolic rates. To investigate the relation...

We surveyed ants in Providence, Rhode Island, from 2015 to 2019. Methods including repeated pitfall trap sampling and manual searching were used to collect ants at Providence College and a rapid biological assess-ment was conducted at Roger Williams Park. A total of 36 species were identified based on morphology, including the first observations of...

Metabolic rates of ectotherms are expected to increase with global trends of climatic warming. But the potential for rapid, compensatory evolution of lower metabolic rate in response to rising temperatures is only starting to be explored. Here, we explored rapid evolution of metabolic rate and locomotor performance in acorn‐dwelling ants (Temnothor...

Thermal tolerance of an organism depends on both the ability to dynamically adjust to a thermal stress and preparatory developmental processes that enhance thermal resistance. However, the extent to which standing genetic variation in thermal tolerance alleles influence dynamic stress responses vs. preparatory processes is unknown. Here, using the...

Insects breathe using a system of tracheal tubes that ramify throughout the body. Rhythmic tracheal compression (RTC), the periodic collapse and reinflation of parts of the system, has been identified in multiple taxa, but little is known about the precise dynamics of tube deformation cycles. It has been hypothesized that during RTC, compression oc...

The physical spaces within which organisms live affect their biology and in many cases can be considered part of their extended phenotype. The nests of social insect societies have a fundamental impact on their ability to function as complex superorganisms. Ants in many species excavate elaborate subterranean nests, but others inhabit relatively sm...

While it is clear that the insect tracheal system can respond in a compensatory manner to both hypoxia and hyperoxia, there is substantial variation in how different parts of the system respond. However, the response of tracheal structures, from the tracheoles to the largest tracheal trunks, have not been studied within one species. In this study,...

Background: Many neuronal and glial diseases have been associated with changes in metabolism. Therefore, metabolic reprogramming has become an important area of research to better understand disease at the cellular level, as well as to identify targets for treatment. Model systems are ideal for interrogating metabolic questions in a tissue depende...

Metabolic rates of individual animals and social insect colonies generally scale hypometrically, with mass-specific metabolic rates decreasing with increasing size. Although this allometry has wide ranging effects on social behaviour, ecology and evolution, its causes remain controversial. Because it is difficult to experimentally manipulate body s...

The metabolic costs of being an organism generally scale hypometrically, such that per‐gram metabolic rates decrease with increasing size. The drivers of this almost universal feature have yet to be clearly identified. Cohesive social groups, particularly the social insects, also show hypometric scaling with colony size. It is not known whether siz...

One of the central questions in physiological ecology is how energetic constraints affect organismal performance and the dynamics of ecological systems. Social insect colonies integrate the balance of supply and demand across levels of biological organization such that the individual components are simultaneously serving as the supply transport net...

Social network analysis provides a broad and complex perspective on animal sociality that is widely applicable to almost any species. Recent applications demonstrate the utility of network analysis for advancing our understanding of the dynamics, selection pressures, development, and evolution of complex social systems. However, most studies of ani...

Rhythmic patterns of compression and reinflation of the thin-walled hollow tubes of the insect tracheal system have been observed in a number of insects. These movements may be important for facilitating the transport and exchange of respiratory gases, but observing and characterizing the dynamics of internal physiological systems within live insec...

Insect tracheal-respiratory systems achieve high fluxes and great dynamic range with low energy requirements and could be important models for bioengineers interested in developing microfluidic systems. Recent advances suggest that insect cardiorespiratory systems have functional valves that permit compartmentalization with segment-specific pressur...

We asked how team dynamics can be captured in relation to function by considering games in the first round of the NBA 2010 play-offs as networks. Defining players as nodes and ball movements as links, we analyzed the network properties of degree centrality, clustering, entropy and flow centrality across teams and positions, to characterize the game...

Weighted graphs of ball movement for all West Coast teams. Red edges represent transition probabilities summing to the percentile indicated in the column header. (PDF)

Starting players and position assignments for the 2010 NBA playoffs, first round. Substitutes are in parentheses. (PDF)

Weighted graphs of ball movement for East Coast teams. Red edges represent transition probabilities summing to the percentile indicated in the column header. (PDF)

Player flow centrality. Flow centrality (FC) is calculated as the proportion of all plays in which a player was involved. Flow centrality based on outcome is calculated as the proportion of successful (FC3 S) or failed (FC3 F) plays in which a player appears as one of the last 3 player possessions in the sequence. (PDF)

Investigating local-scale interactions within a network makes it possible to test hypotheses about the mechanisms of global network connectivity and to ask whether there are general rules underlying network function across systems. Here we use motif analysis to determine whether the interactions within social insect colonies resemble the patterns e...

Video recording of a paint-marked Pogonomyrmex californicus colony (QuickTime; 7.3 MB). (MOV)

Classification and identification of network motifs (PDF; 266 KB). (PDF)

Network degree distributions (PDF; 938 KB). (PDF)

Effect of analysis time on motif analysis (PDF; 578 KB). (PDF)

1 Insect metabolic rates are highly variable and are affected by environmental, behavioral, developmental, and evolutionary factors. 2 The effects of temperature on insect metabolic rates depend on their behavior, life-history stage, morphology, and size. In many cases, inactive insect metabolic rates increase with temperature in a manner consisten...

Insects in general, and Drosophila in particular, are much more capable of surviving anoxia than vertebrates, and the mechanisms involved are of considerable biomedical and ecological interest. Temperature is likely to strongly affect both the rates of damage occurring in anoxia and the recovery processes in normoxia, but as yet there is no informa...

The negative allometric scaling of metabolic rate with body size is among the most striking patterns in biology. We investigated whether this pattern extends to physically independent eusocial systems by measuring the metabolic rates of whole functioning colonies of the seed-harvester ant Pogonomyrmex californicus. These intraspecific scaling data...

Rhythmic tracheal compression is a prominent feature of internal dynamics in multiple orders of insects. During compression parts of the tracheal system collapse, effecting a large change in volume, but the ultimate physiological significance of this phenomenon in gas exchange has not been determined. Possible functions of this mechanism include to...

Rhythmic compressive movements in the tracheal system in the carabid beetle Platynus decentis, demonstrating the utility of phase-contrast synchrotron imaging for studies of respiratory dynamics in small animals. View (1.3 × 1.0 mm) is a dorsoventral projection through prothorax of a beetle (mass ~ 45 mg) using monochromatic x-rays (25 keV). The mi...

Passage of food bolus through the esophagus of the butterfly Pieris rapae. View (1.3 × 1.0 mm) is a lateral projection through the thorax of the butterfly (mass ~50 mg), with food moving from anterior (upper right) to posterior (lower left). The butterfly was feeding on a mixture of sugar water and iodine compound (Isovue). X-ray energy (33.2 keV)...

Movements of the foregut and gut contents of the carabid beetle Pterostichus stygicus. View (3.3 × 2.5 mm) is a dorsoventral projection through the pterothorax, posterior to the mesocoxae (circular structures seen at top of image). The beetle (mass ~210 mg) was fed macerated larva sprinkled with cadmium powder to increase x-ray (25 keV) absorption...

Despite advances in imaging techniques, real-time visualization of the structure and dynamics of tissues and organs inside small living animals has remained elusive. Recently, we have been using synchrotron x-rays to visualize the internal anatomy of millimeter-sized opaque, living animals. This technique takes advantage of partially-coherent x-ray...

Although the internal physiological dynamics of large species, especially humans, are well understood, this is not true for small millimeter-sized animals such as insects. Because of their size and in general, optically opaque exteriors, direct visualization of internal insect physiology has not been possible. As such, biologists have relied on ind...