Eldridge Adams - US grants

9423628 ADAMS Social insects are an ecologically and economically important group of organisms. The structure of social insect colonies has long been of interest because workers sacrifice their own reproductive opportunities and help raise the offspring of others. While many studies of colony-level genetic relatedness have been conducted on the social ants, bees and wasps, little is known about the genetic structure of termite colonies. It is important to learn more about termites because, although their social organization is similar to the other social insects, their social structure appears to have evolved independently and other aspects of their biology have apparently produced relatedness relationships unlike those found in other social insects. This research examines the Neotropical termite Nasutitermes corniger, an abundant, destructive and easily collected species that has multiple queens and kings in many of its colonies. Protein and DNA genetic markers will be used to examine: 1) the numbers of reproducing queens and kings per colony; 2) their relatedness; 3) mating patterns, and 4) offspring production per queen and king. Genetic structure will be assessed at both the colony and population levels.

Animal Behavior Program
Nontechnical Abstract


Proposal #: 9874451
PI: Eldridge S. Adams
Title: "Neighborhood interactions and territory size in the fire ant"


For many animals, the defense of foraging territories serves as an
important mechanism of population regulation. Models of territory size can
help to understand the population ecology of these species by predicting
how the partitioning of territories changes in response to variation in
food supply or competitive environment. A recent model predicts territory
sizes and shapes for contiguous neighbors as a result of competitive
interactions at territory boundaries. This research tests and extends this
model through a series of field experiments on colonies of the fire ant
Solenopsis invicta. Methods will include manipulations of colony sizes and
competitive neighborhoods, controlled supplements of food density in local
patches and across pairs of territories, standardized measurements of
aggression, and game theoretical models of territory interactions.

This work will develop a general approach to the study of territoriality,
and other interactions, for which the spatial outcome of one individual's
actions depend on the decisions and reactions of multiple neighbors. This
approach can be applied to a wide variety of habitats and animals,
including both vertebrates and invertebrates. A specific model will be
developed and tested for the fire ant. This information will be used to
improve prediction of population dynamics for this important insect pest.

The control of reproduction is fundamental to the structure and evolution of animal societies. This project will examine the causes and consequences of variation in the breeding structure of colonies of the termite Nasutitermes corniger, focusing on the number of reproductive males and females (kings and queens) and their apportionment of reproduction. The wide range of colony genetic structures present within natural populations provides opportunities to test hypotheses arising from the rapidly growing body of theory on reproductive partitioning in social groups. Nest dissections, behavioral assays, and analysis of a highly informative set of genetic markers will determine (1) how reproduction is partitioned among co-occurring queens and kings, (2) how colony genetic structure affects interactions within and between groups, and (3) how colony reproductive characteristics change through time.

Despite their ecological and economic importance, termites are understudied relative to other social insects. Nasutitermes corniger is particularly well suited to the proposed research due to its abundance and to the comparative ease with which the queens and kings can be collected from mature colonies. Besides adding to knowledge of fundamental aspects of termite biology, this research will contribute to the broader understanding of social behavior, reproductive competition, and the genetic structure of populations.