Does visual or mechanosensory disruption influence risk assessment in coral reef fishes: a preliminary study.

Interpreting and responding to environmental cues from different modalities has survival value. In fish, the role of multimodal perception has been studied in regard to both foraging and risk assessment, with modalities including vision, olfaction, and mechanoreception via lateral lines. We studied reef fish boldness by placing novel objects that obstructed vision, lateral line use, or both into a coral reef environment with native algal samples inside, and then quantifying exploration as a function of obstruction type and as a function of functional diet groups (herbivores, omnivores, carnivores).

Foraging behaviour affects nest architecture in a cross-species comparison of ant nests.

Animals construct and inhabit nests that can exhibit dramatic intra- and interspecific variation due to differences in behaviour, the biotic and abiotic environment, and evolutionary history. In ants, variation in nest architecture reflects both differences in ecology and in the collective behaviour of the colonies that live in the nests. Each component of the nest (such as depth, and the number, size and connectivity of chambers) reflects selective pressures for different functions, or structural constraints that are imposed by the environment or evolutionary history.

Harvester ant nest architecture is more strongly affected by intrinsic than extrinsic factors.

Behavior is shaped by genes, environment, and evolutionary history in different ways. Nest architecture is an extended phenotype that results from the interaction between the behavior of animals and their environment. Nests built by ants are extended phenotypes that differ in structure among species and among colonies within a species, but the source of these differences remains an open question.

Modularity and connectivity of nest structure scale with colony size.

Large body sizes have evolved structures to facilitate resource transport. Like unitary organisms, social insect colonies must transport information and resources. Colonies with more individuals may experience transport challenges similar to large-bodied organisms.

The benefits of being big and diverse: early colony survival in harvester ants.

In sessile organisms such as plants and benthic invertebrates, founding propagules typically suffer extremely high rates of mortality due to both extrinsic and intrinsic factors. Many social insect species share similarities with these groups, but factors influencing early colony survival are relatively unstudied. We used a field experiment to measure the importance of environmental quality relative to intrinsic colony properties in the harvester ant, Pogonomyrmex occidentalis, by monitoring the survival of 584 experimental colonies.