| |
Records |
Links |
|
Author |
Fischhoff, I.; Dushoff, J.; Sundaresan, S.; Cordingley, J.; Rubenstein, D. |
|
| |
Title |
Reproductive status influences group size and persistence of bonds in male plains zebra (Equus burchelli) |
Type |
Journal Article |
| |
Year |
2009 |
Publication |
Behavioral Ecology and Sociobiology |
Abbreviated Journal |
Behav. Ecol. Sociobiol. |
|
| |
Volume |
63 |
Issue |
7 |
Pages |
1035-1043-1043 |
|
| |
Keywords |
Biomedical and Life Sciences |
|
| |
Abstract |
Animal groups arise from individuals’ choices about the number, characteristics, and identity of associates. Individuals make these choices to gain benefits from their associations. As the needs of an individual change with its phenotype, so too we expect the nature of its associations to vary. In this paper, we investigate how the social priorities of male plains zebra (Equus burchelli) depend on reproductive state. An adult male is either a bachelor, and lacking mating access, or a stallion defending a harem. Multiple harems and bachelor males aggregate in larger herds. Herds frequently split and merge, affording males opportunities to change associates. Over a 4-year period, we sampled the herd associations in a population of 500–700 zebras. To isolate the effects of reproductive state on male social behavior, we account for potential confounding factors: changes in population size, grouping tendencies, and sampling intensity. We develop a generally applicable permutation procedure, which allows us to test the null hypothesis that social behavior is independent of male status. Averaging over all individuals in the population, we find that a typical bachelor is found in herds containing significantly more adults, bachelors, and stallions than the herds of a typical stallion. Further, bachelors’ bonds with each other are more persistent over time than those among stallions. These results suggest that bachelors form cohesive cliques, in which we may expect cooperative behaviors to develop. Stallion–stallion associations are more diffuse, and less conducive to long-term cooperation. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Springer Berlin / Heidelberg |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0340-5443 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial  |
5193 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Gueron, S.; Levin, S.A.; Rubenstein, D.I. |
|
| |
Title |
The Dynamics of Herds: From Individuals to Aggregations |
Type |
Journal Article |
| |
Year |
1996 |
Publication |
Journal of Theoretical Biology |
Abbreviated Journal |
J. Theor. Biol. |
|
| |
Volume |
182 |
Issue |
1 |
Pages |
85-98 |
|
| |
Keywords |
|
|
| |
Abstract |
The dynamic behavior of small herds is investigated by means of simulations of two-dimensional discrete-stochastic models. An individual-based approach is used to relate collective behavior to individual decisions. In our model, the motion of an individual in a herd is assumed to be the combined result of both density-independent and density-dependent decisions, in the latter case based on the influence of surrounding neighbors; assumed decision rules are hierarchical, balancing short range repulsion against long-range attraction. The probability of fragmentation of the model herd depends on parameter values. We explore the variety and characteristics of spatial patterns that develop during migration, for herds that are homogeneous and heterogeneous regarding intrinsic walking speeds. Group integrity can be maintained even in mixed populations, but fragmentation results for these more easily than for a homogeneous herd. Observations of natural populations suggest that animals move away from individuals that intrude too closely into their environment, but are attracted to individuals at a distance. Between these extremes, there appears to be a neutral zone, within which other individuals engender no response. We explore the importance of this neutral zone, and offer evolutionary interpretations. In particular, the neutral zone, if not too large, permits the individual to remain in contact with the herd, while reducing the frequency with which acceleration or deceleration must be undertaken. This offers obvious energetic benefits. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-5193 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5253 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Parker, G.A.; Rubenstein, D.I. |
|
| |
Title |
Role assessment, reserve strategy, and acquisition of information in asymmetric animal conflicts |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
29 |
Issue |
1 |
Pages |
221-240 |
|
| |
Keywords |
|
|
| |
Abstract |
It was formerly argued that alternative evolutionarily stable strategies (ESSs) are possible for animal contests characterized by some asymmetry that can be perceived with perfect accuracy. Where roles A and B refer to the asymmetry between opponents, ESSs are: [`]fight when A, retreat when B', and vice versa. Either can be an ESS, but only if the [`]reserve strategy' (=what an animal does when it fights) is sufficiently damaging. We examine the [`]war of attrition' (winner = opponent that persists longer). In a population at either ESS, reserve strategy is never normally shown; it is therefore subject to drift unless the selective action of rare individuals which break the convention is considered. These could arise either by mutation or by mistakes in role assessment. When mutations and mistakes simply specify that occasionally an animal fights when it [`]should' retreat, selection adjusts reserve strategy to a level where only one ESS (the [`]commonsense' ESS) is possible, if the asymmetry is relevant to payoff. Thus for asymmetries in fighting ability or resource value, the individual with the lower score will retreat. However, we are particularly concerned with cases where both payoff-relevant aspects (fighting ability and resource value) are asymmetric. If opponents sustain contest costs at rates KA and KB, and their resource values are VA and VB, an [`]optimal assessor' strategy defined by the interaction between the two asymmetries, is a unique ESS. It obeys the rule [`]fight on estimating role A, where VA/KA>VB/KB; retreat in B'. If mistakes can occur in both roles, but are very rate, the ESS is not fundamentally altered though there will be infinitesimal tendencies for persisting in role B. Selection to improve assessment abilities intensifies as abilities improve, but is weak if roles A and B are rather similar. Over a range of similarity between roles, an [`]owner wins' convention may be adopted if ownership correlates positively with role A and an individual cannot tell when it would otherwise pay him to break the convention. We also examine a contest in which information about roles can be acquired only during a contest itself, and at a cost. Much depends on the rate at which information is acquired relative to the rate at which costs are expended, and on whether contests normally escalate in intensity, remain at the same level, or de-escalate. Selection favours short contests when costs are high relative to resource value, where the outcome of a round contains much information about fighting ability, and where the actual disparity in fighting ability is large. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0003-3472 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5325 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rubenstein, D. |
|
| |
Title |
Wild Equid Movements: Impacts of Habitat Quality, Predation Pressure and Leadership |
Type |
Conference Article |
| |
Year |
2012 |
Publication |
Proceedings of the 2. International Equine Science Meeting |
Abbreviated Journal |
Proc. 2. Int. Equine. Sci. Mtg |
|
| |
Volume |
in press |
Issue |
|
Pages |
|
|
| |
Keywords |
|
|
| |
Abstract |
Animals spend much of their lives on the move searching for food, shelter and mates. As long-legged, large bodied species, equids are well suited for traveling long distances. Understanding where free-ranging equids go, why they choose particular locations, some near and some far, and what impact such movements have on patterns of sociality, demography and human livelihoods are only now coming into focus. This talk will explore how bottom-up factors, such as the abundance and distribution of key resources, and top-down factors, such as the type and location of predators, interact to shape overall movement patterns of equids, how leadership roles develop and what outcomes such movements are likely to have on human activities. |
|
| |
Address |
|
|
| |
Corporate Author |
Rubenstein, D. |
Thesis |
|
|
| |
Publisher |
Xenophon Publishing |
Place of Publication |
Wald |
Editor |
Krueger, K. |
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
978-3-9808134-26 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5556 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Nuñez, C.M.V.; Adelman, J.S.; Smith, J.; Gesquiere, L.R.; Rubenstein, D.I. |
|
| |
Title |
Linking social environment and stress physiology in feral mares (Equus caballus): Group transfers elevate fecal cortisol levels |
Type |
Journal Article |
| |
Year |
2014 |
Publication |
General and Comparative Endocrinology |
Abbreviated Journal |
|
|
| |
Volume |
196 |
Issue |
|
Pages |
26-33 |
|
| |
Keywords |
Equus caballus; Fecal cortisol; Feral mare; Group transfer; Stress; Social instability |
|
| |
Abstract |
Abstract Feral horses (Equus caballus) have a complex social structure, the stability of which is important to their overall health. Behavioral and demographic research has shown that decreases in group (or band) stability reduce female fitness, but the potential effects on the physiological stress response have not been demonstrated. To fully understand how band stability affects group-member fitness, we need to understand not only behavioral and demographic, but also physiological consequences of decreases to that stability. We studied group changes in feral mares (an activity that induces instability, including both male and female aggression) on Shackleford Banks, NC. We found that mares in the midst of changing groups exhibit increased fecal cortisol levels. In addition, mares making more group transfers show higher levels of cortisol two weeks post-behavior. These results offer insights into how social instability is integrated into an animal’s physiological phenotype. In addition, our results have important implications for feral horse management. On Shackleford Banks, mares contracepted with porcine zona pellucida (PZP) make approximately 10 times as many group changes as do untreated mares. Such animals may therefore be at higher risk of chronic stress. These results support the growing consensus that links between behavior and physiological stress must be taken into account when managing for healthy, functional populations. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0016-6480 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5743 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Rubenstein, D. |
|
| |
Title |
Social Networks: Linking Form with Function in Equid Societies |
Type |
Conference Article |
| |
Year |
2015 |
Publication |
Proceedings of the 3. International Equine Science Meeting |
Abbreviated Journal |
Proc. 3. Int. Equine. Sci. Mtg |
|
| |
Volume |
|
Issue |
|
Pages |
|
|
| |
Keywords |
|
|
| |
Abstract |
Animal societies develop from interactions and relationships that occur among individuals within populations. The fundamental tenet of behavioral ecology is that ecological factors shape behavior and determine the distribution and associations of individuals on landscapes. As a result, different social systems emerge in different habitats and under different environmental conditions. Since characterizing social systems depends on time and motion studies of individual actions and interactions that are often bilateral, such characterizations are often coarse-grained. If social relationships can be characterized using social networks, however, seemingly similar social organizations often reveal informative differences in terms of deep structure. Thus social network theory should be able to provide insights in to the connections between social form and function. This talk will explore how the network structures of horses, zebras and asses can provide novel insights into the functioning of animal societies with respect to the spread of memes, genes and diseases. |
|
| |
Address |
|
|
| |
Corporate Author |
Rubenstein, D. |
Thesis |
|
|
| |
Publisher |
Xenophon Publishing |
Place of Publication |
Wald |
Editor |
Krueger, K. |
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
Proc. 3. Int. Equine. Sci. Mtg |
|
| |
Series Volume |
in prep |
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
978-3-95625-000-2 |
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Id - |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5797 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Zhang, Y.; Cao, Q.S.; Rubenstein, D.I.; Zang, S.; Songer, M.; Leimgruber, P.; Chu, H.; Cao, J.; Li, K.; Hu, D. |
|
| |
Title |
Water Use Patterns of Sympatric Przewalski's Horse and Khulan: Interspecific Comparison Reveals Niche Differences |
Type |
Journal Article |
| |
Year |
2015 |
Publication |
Plos One |
Abbreviated Journal |
Plos One |
|
| |
Volume |
10 |
Issue |
7 |
Pages |
e0132094 |
|
| |
Keywords |
|
|
| |
Abstract |
Acquiring water is essential for all animals, but doing so is most challenging for desert-living animals. Recently Przewalski's horse has been reintroduced to the desert area in China where the last wild surviving member of the species was seen before it vanished from China in the1960s. Its reintroduction placed it within the range of a close evolutionary relative, the con-generic Khulan. Determining whether or not these two species experience competition and whether or not such competition was responsible for the extinction of Przewalski's horses in the wild over 50 years ago, requires identifying the fundamental and realized niches of both species. We remotely monitored the presence of both species at a variety of water points during the dry season in Kalamaili Nature Reserve, Xinjiang, China. Przewalski's horses drank twice per day mostly during daylight hours at low salinity water sources while Khulans drank mostly at night usually at high salinity water points or those far from human residences. Spatial and temporal differences in water use enables coexistence, but suggest that Przewalski's horses also restrict the actions of Khulan. Such differences in both the fundamental and realized niches were associated with differences in physiological tolerances for saline water and human activity as well as differences in aggression and dominance. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Public Library of Science |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
6377 |
|
| Permanent link to this record |
