Gender in Science and Engineering Faculties: Demographic Inertia Revisited.

The under-representation of women on faculties of science and engineering is ascribed in part to demographic inertia, which is the lag between retirement of current faculty and future hires. The assumption of demographic inertia implies that, given enough time, gender parity will be achieved. We examine that assumption via a semi-Markov model to predict the future faculty, with simulations that predict the convergence demographic state.

Darwin's 'one special difficulty': celebrating Darwin 200.

Darwin identified eusocial evolution, especially of complex insect societies, as a particular challenge to his theory of natural selection. A century later, Hamilton provided a framework for selection on inclusive fitness. Hamilton's rule is robust and fertile, having generated multiple subdisciplines over the past 45 years.

Impact of parasite sympatry on the geographic mosaic of coevolution.

Slave-making ants are specialized social parasites that steal the young from colonies of their host species to augment their slave supply. The degree of parasite-host specialization has been shown to shape the trajectory along which parasites and hosts coevolve and is a prime contributor to the geographic mosaic of coevolution. However, virtually nothing is known about extrinsic influences on parasite-host dynamics, although the simple addition of a competing slave-maker may significantly alter selection pressures.

COMPLEX COLONY STRUCTURE IN SOCIAL INSECTS: I. ECOLOGICAL DETERMINANTS AND GENETIC CONSEQUENCES.

For social insect species, intraspecific variation in colony social structure provides an opportunity to relate the evolution of social behavior to ecological factors. The species Myrmica punctiventris is a cavity-dwelling forest ant that exhibits very different colony structures in two populations in the northeastern United States. Combined data from seasonal censuses, allozyme electrophoresis, and worker hostility tests showed that a population of M.

COMPLEX COLONY STRUCTURE IN SOCIAL INSECTS: II. REPRODUCTION, QUEEN-WORKER CONFLICT, AND LEVELS OF SELECTION.

Differences in colony structure between two populations of the forest ant, Myrmica punctiventris, have had dramatic consequences on allocation to growth and reproduction. A population in Vermont, in which colonies have a single, once-mated queen, shows no evidence of inbreeding or population subdivision and has allocated 25% of sexual reproduction to males in two consecutive years. In contrast, for a population in New York that is facultatively polygynous, we have evidence of microgeographic genetic structure and inbreeding, and the populationwide allocation ratio was extremely male-biased.

Community structure in north temperate ants: temporal and spatial variation.

Ant communities in Vermont and New York woods were sampled in four time periods to determine species composition, relative abundances, and nest locations in space. The Vermont community was richer, containing more species and higher nest densities than New York. Both communities followed the geometric distribution of species abundances, suggesting that a single resource was mediating competition.

Time resources and laziness in animals.

Investigations of time budgets reveal that for many animals a surprising proportion of their active time is spent in inactivity. The question of why these beasts are often idle is investigated by examining their foraging behavior in a model which does not utilize optimization criteria. If an organism's goal is to stay alive, one satisfactory strategy is a thermostat feeding process whereby the animal initiates foraging when it perceives hunger and ceases when it becomes satiated.