tion of data for a particular topic and synthesize two or
more disciplines to create new theory with new predictions.
A Synthesis of Disciplines and New Paradigms
Many chapters included in Rodent Societiescover topics
that occur in most behavior texts (e.g., Alcock 2005; Du-
gatkin 2003). However, we encouraged authors to go be-
yond summarizing current knowledge to develop new par-
adigms by combining ideas from various disciplines. For
example, Kalcounis-Rüppell and Ribble (chap. 6) provide a
phylogenetic analysis of life history and physiological cor-
relates of male and female mating strategies in which they
conclude that litter mass and distributional range of a spe-
cies are good predictors of the occurrence of paternal care.
Dobson and Oli (chap. 8) present a model of reproduc-
tive effort involving “fast and slow” life histories that is ul-
timately based on demography. The authors attempted to
understand if developmental stage at birth might become a
constraint on the ontogeny of reproductive effort and other
life history variables. Albrecht Schulte-Hostedde (chap. 10)
applies sexual selection and parental investment theory to
investigate how ecological and energetic constraints might
limit sexual dimorphism, independent of the mating sys-
tem. Schulte-Hostedde presents two alternative hypotheses
to illustrate how the energetics of reproduction, sexual se-
lection, and costs of extreme climatic conditions interact to
limit sexual dimorphism in chipmunks.
The idea that stress plays an important role in reproduc-
tion and population demography is well known. However,
Boonstra et al. (chap. 12) provide a new synthesis of how
stress affects survival and mating success. In chapter 14
Dobson proposes that social genetic structuring can oc-
cur in breeding groups in which males are polygynous and
females are philopatric. He defines the conditions under
which social behavior, primarily social groupings of females
and behavioral influences on mating systems, influence gene
dynamics. Krebs, Lambin, and Wolff (chap. 15) join forces
to synthesize behavioral, ecological, and evolutionary the-
ory to address the potential for self-regulation in rodent
population dynamics. Likewise, Curtis et al. (chap.16) com-
bine research on hormones, brain function, and social be-
havior as they relate to affiliative and paternal care lead-
ing to monogamy, to develop a new paradigm in neural
behavior. Another synthesis of disciplines is Owings and
Coss’s (chap. 26) exploration of the processes that gener-
ate connections between rodent anti-predator behavior and
social systems. They note that although the social and anti-
predatory domains are partially independent sources of nat-
ural selection, both select for phenotypes through modifi-
cations in developmental systems. Combining paradigms
from ontogeny of development, risk avoidance, kin selec-
tion, cognition, and sociality, the authors provide a novel
synthesis.
Further examples of new paradigms are provided by
Ylönen and Brown (chap. 28) in which they apply optimal
foraging strategies and life history parameters to avoidance
of predation risk. Similarly, Armitage (chap. 30) synthesizes
physiology and social behavior, proposing that energetic
constraints and costs of hibernation select for sociality in
marmots. Conceptual and predictive models to explain the
probable adaptive significance of the continuum of social
systems from asociality through eusociality are provided for
subterranean rodents (Lacey and Sherman, chap. 21), blind
mole-rats (Nevo, chap. 25), ground squirrels (Hare and
Murie, chap. 29), kangaroo rats (Randall, chap. 31), and
African mole-rats (Faulkes and Bennett, chap. 36).
The scope of many of these chapters can be attributed to
the wide range of species studied within a subgroup of ro-
dents. It is this relatively large database of similar studies
on phylogenetically and ecologically similar species that al-
lowed authors to use the comparative approach to develop
conceptual models to predict how extrinsic (ecological) and
intrinsic (genetic) variables interact to affect the formation
and structure of rodent societies.Comparative Behavioral EcologyThe comparative method is a useful approach to develop
and test evolutionary hypotheses (e.g., Barash 1989; Har-
vey and Pagel 1991; Komers and Brotherton 1997). This ap-
proach utilizes comparable data, often from related or sim-
ilar species collected under similar conditions (to control
for some environmental or social variable) and character
mapping with appropriate statistical analyses (to control
for phylogeny). Sufficient comparative data are available for
particular groups of rodents and associated theory is devel-
oped well enough to support such studies. Therefore, we in-
cluded a section on Comparative Socioecology.
Rodents are excellent models for using the comparative
method to develop paradigms and test hypotheses in so-
cioecology, as illustrated here in chapters on kinship and
sociality in ground squirrels (Hare and Murie, chap. 29),
the role of hibernation in the evolution of sociality in mar-
mots (Armitage, chap. 30), environmental constraints on
sociality in desert rodents (Randall, chap. 31), adapta-
tions of commensal rats and mice (Berdoy and Drickamer,
chap. 32), group living in social South American species
(Macdonald et al., chap. 33; Lacey and Ebensperger,
chap. 34), the uniqueness of rock-dwelling rodents (Nutt,
chap. 35), social and ecological diversity of African mole-
rats (Faulkes and Bennett, chap. 36), and comparison of6 Chapter One