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Author | Lee, R.D. | ||||
Title | Rethinking the evolutionary theory of aging: transfers, not births, shape senescence in social species | Type | Journal Article | ||
Year | 2003 | Publication | Proceedings of the National Academy of Sciences of the United States of America | Abbreviated Journal | Proc Natl Acad Sci U S A |
Volume | 100 | Issue | 16 | Pages | 9637-9642 |
Keywords | Adaptation, Physiological; *Aging; Animals; *Biological Evolution; Demography; Economics; Environment; Fertility; Humans; Life Expectancy; Longevity; Models, Theoretical; Parturition; Population Dynamics; Population Growth; Reproduction | ||||
Abstract | The classic evolutionary theory of aging explains why mortality rises with age: as individuals grow older, less lifetime fertility remains, so continued survival contributes less to reproductive fitness. However, successful reproduction often involves intergenerational transfers as well as fertility. In the formal theory offered here, age-specific selective pressure on mortality depends on a weighted average of remaining fertility (the classic effect) and remaining intergenerational transfers to be made to others. For species at the optimal quantity-investment tradeoff for offspring, only the transfer effect shapes mortality, explaining postreproductive survival and why juvenile mortality declines with age. It also explains the evolution of lower fertility, longer life, and increased investments in offspring. | ||||
Address | Department of Demography, University of California, 2232 Piedmont Avenue, Berkeley, CA 94720-2120, USA. rlee@demog.berkeley.edu | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0027-8424 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:12878733 | Approved | no | ||
Call Number | Equine Behaviour @ team @ | Serial | 5465 | ||
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Author | Kirkpatrick, J.F.; Liu, I.M.; Turner, J.W.J.; Naugle, R.; Keiper, R. | ||||
Title | Long-term effects of porcine zonae pellucidae immunocontraception on ovarian function in feral horses (Equus caballus) | Type | Journal Article | ||
Year | 1992 | Publication | Journal of reproduction and fertility | Abbreviated Journal | J Reprod Fertil |
Volume | 94 | Issue | 2 | Pages | 437-444 |
Keywords | Animals; Contraception, Immunologic/*veterinary; *Egg Proteins; Estrogens, Conjugated (USP)/urine; Female; Glycoproteins/*pharmacology; Horses/immunology/*physiology; *Membrane Glycoproteins; Ovary/drug effects/*physiology; Progesterone/metabolism; *Receptors, Cell Surface; Swine/immunology; Time Factors; Zona Pellucida/*immunology | ||||
Abstract | Ten feral mares free-roaming in Maryland, USA, were inoculated with porcine zonae pellucidae (PZP) protein before the breeding season for three consecutive years (1988-90). Ovarian function was monitored for 51 days during the peak of the breeding season after the third annual PZP inoculation, in seven of these mares and in four untreated control mares, by means of urinary oestrone conjugates and nonspecific progesterone metabolites. None of the ten inoculated mares became pregnant in 1990, compared with 55% of 20 control mares, which included two of the four monitored for ovarian function. Three of the untreated mares demonstrated apparent normal ovarian activity, characterized by preovulatory oestrogen peaks, concurrent progesterone nadirs at ovulation, breeding activity, and luteal-phase progesterone increases after ovulation. Two of the seven monitored PZP-treated mares demonstrated ovulatory cycles that did not result in conception. One was pregnant as a result of conception in 1989 and demonstrated a normal, late-gestation, endocrine profile. The remaining four PZP-treated mares revealed no evidence of ovulation, and urinary oestrogen concentrations were significantly depressed. The experiments indicated that (i) a third consecutive annual PZP booster inoculation is greater than 90% effective in preventing pregnancies in mares and (ii) three consecutive years of PZP treatment may interfere with normal ovarian function as shown by markedly depressed oestrogen secretion. | ||||
Address | Deaconess Research Institute, Billings, MT 59102 | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-4251 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:1317449 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 145 | ||
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Author | Skov-Rackette, S.I.; Shettleworth, S.J. | ||||
Title | What do rats learn about the geometry of object arrays? Tests with exploratory behavior | Type | Journal Article | ||
Year | 2005 | Publication | Journal of experimental psychology. Animal behavior processes | Abbreviated Journal | J Exp Psychol Anim Behav Process |
Volume | 31 | Issue | 2 | Pages | 142-154 |
Keywords | Animals; Behavior, Animal; *Discrimination Learning; *Exploratory Behavior; Female; *Form Perception; Habituation, Psychophysiologic; Male; Rats; Rats, Long-Evans | ||||
Abstract | Six experiments using habituation of exploratory behavior tested whether disoriented rats foraging in a large arena encode the shapes of arrays of objects. Rats did not respond to changes in position of a single object, but they responded to a change in object color and to a change in position of 1 object in a square array, as in previous research (e.g., C. Thinus-Blanc et al., 1987). Rats also responded to an expansion of a square array, suggesting that they encoded sets of interobject distances rather than overall shape. In Experiments 4-6, rats did not respond to changes in sense of a triangular array that maintained interobject distances and angles. Shapes of object arrays are encoded differently from shapes of enclosures. | ||||
Address | Department of Psychology, University of Toronto, Toronto, ON M5S 3G3, Canada. shannon.skov.rackette@utoronto.ca | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0097-7403 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:15839772 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 363 | ||
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Author | Shettleworth, S.J.; Sutton, J.E. | ||||
Title | Multiple systems for spatial learning: dead reckoning and beacon homing in rats | Type | Journal Article | ||
Year | 2005 | Publication | Journal of experimental psychology. Animal behavior processes | Abbreviated Journal | J Exp Psychol Anim Behav Process |
Volume | 31 | Issue | 2 | Pages | 125-141 |
Keywords | Animals; Behavior, Animal; Cues; *Feeding Behavior; Habituation, Psychophysiologic; *Homing Behavior; *Learning; Male; Rats; Rats, Long-Evans; *Space Perception | ||||
Abstract | Rats homed with food in a large lighted arena. Without visual cues, they used dead reckoning. When a beacon indicated the home, rats could also use the beacon. Homing did not differ in 2 groups of rats, 1 provided with the beacon and 1 without it; tests without the beacon gave no evidence that beacon learning overshadowed dead reckoning (Experiment 1). When the beacon was at the home for 1 group and in random locations for another, there was again no evidence of cue competition (Experiment 2). Dead reckoning experience did not block acquisition of beacon homing (Experiment 3). Beacon learning and dead reckoning do not compete for predictive value but acquire information in parallel and are used hierarchically. | ||||
Address | Department of Psychology, University of Toronto, Toronto, ON M5S 3G3, Canada. shettle@psych.utoronto.ca | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0097-7403 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:15839771 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 364 | ||
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Author | Gibson, B.M.; Shettleworth, S.J. | ||||
Title | Competition among spatial cues in a naturalistic food-carrying task | Type | Journal Article | ||
Year | 2003 | Publication | Learning & behavior : a Psychonomic Society publication | Abbreviated Journal | Learn Behav |
Volume | 31 | Issue | 2 | Pages | 143-159 |
Keywords | Adaptation, Psychological; Animals; Appetitive Behavior; *Association Learning; *Attention; Choice Behavior; *Cues; *Discrimination Learning; Male; Rats; Rats, Long-Evans; Space Perception; *Spatial Behavior | ||||
Abstract | Rats collected nuts from a container in a large arena in four experiments testing how learning about a beacon or cue at a goal interacts with learning about other spatial cues (place learning). Place learning was quick, with little evidence of competition from the beacon (Experiments 1 and 2). Rats trained to approach a beacon regardless of its location were subsequently impaired when the well-learned beacon was removed and other spatial cues identified the location of the goal (Experiment 3). The competition between beacon and place cues reflected learned irrelevance for place cues (Experiment 4). The findings differ from those of some studies of associative interactions between cue and place learning in other paradigms. | ||||
Address | University of Toronto, Toronto, Ontario, Canada | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1543-4494 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:12882373 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 368 | ||
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Author | Viscido, S.V.; Miller, M.; Wethey, D.S. | ||||
Title | The dilemma of the selfish herd: the search for a realistic movement rule | Type | Journal Article | ||
Year | 2002 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
Volume | 217 | Issue | 2 | Pages | 183-194 |
Keywords | Animals; *Behavior, Animal; *Mass Behavior; Models, Biological; *Motor Activity; Predatory Behavior | ||||
Abstract | The selfish herd hypothesis predicts that aggregations form because individuals move toward one another to minimize their own predation risk. The “dilemma of the selfish herd” is that movement rules that are easy for individuals to follow, fail to produce true aggregations, while rules that produce aggregations require individual behavior so complex that one may doubt most animals can follow them. If natural selection at the individual level is responsible for herding behavior, a solution to the dilemma must exist. Using computer simulations, we examined four different movement rules. Relative predation risk was different for all four movement rules (p<0.05). We defined three criteria for measuring the quality of a movement rule. A good movement rule should (a) be statistically likely to benefit an individual that follows it, (b) be something we can imagine most animals are capable of following, and (c) result in a centrally compact flock. The local crowded horizon rule, which allowed individuals to take the positions of many flock-mates into account, but decreased the influence of flock-mates with distance, best satisfied these criteria. The local crowded horizon rule was very sensitive to the animal's perceptive ability. Therefore, the animal's ability to detect its neighbors is an important factor in the dynamics of group formation. | ||||
Address | Department of Biological Sciences, University of South Carolina, Columbia, SC, 29208, USA. viscido@u.washington.edu | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | 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 | PMID:12202112 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 554 | ||
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Author | Suzuki, Y.; Toquenaga, Y. | ||||
Title | Effects of information and group structure on evolution of altruism: analysis of two-score model by covariance and contextual analyses | Type | Journal Article | ||
Year | 2005 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
Volume | 232 | Issue | 2 | Pages | 191-201 |
Keywords | *Altruism; Analysis of Variance; *Communication; Cooperative Behavior; *Evolution; Game Theory; *Group Structure; Humans; Models, Genetic; Models, Psychological; Selection (Genetics); Trust | ||||
Abstract | An altruistic individual has to gamble on cooperation to a stranger because it does not know whether the stranger is trustworthy before direct interaction. Nowak and Sigmund (Nature 393 (1998a) 573; J. Theor. Biol. 194 (1998b) 561) presented a new theoretical framework of indirect reciprocal altruism by image scoring game where all individuals are informed about a partner's behavior from its image score without direct interaction. Interestingly, in a simplified version of the image scoring game, the evolutionarily stability condition for altruism became a similar form of Hamilton's rule, i.e. inequality that the probability of getting correct information is more than the ratio of cost to benefit. Since the Hamilton's rule was derived by evolutionarily stable analysis, the evolutionary meaning of the probability of getting correct information has not been clearly examined in terms of kin and group selection. In this study, we applied covariance analysis to the two-score model for deriving the Hamilton's rule. We confirmed that the probability of getting correct information was proportional to the bias of altruistic interactions caused by using information about a partner's image score. The Hamilton's rule was dependent on the number of game bouts even though the information reduced the risk of cooperation to selfish one at the first encounter. In addition, we incorporated group structure to the two-score model to examine whether the probability of getting correct information affect selection for altruism by group selection. We calculated a Hamilton's rule of group selection by contextual analysis. Group selection is very effective when either the probability of getting correct information or that of future interaction, or both are low. The two Hamilton's rules derived by covariance and contextual analyses demonstrated the effects of information and group structure on the evolution of altruism. We inferred that information about a partner's behavior and group structure can produce flexible pathways for the evolution of altruism. | ||||
Address | Integrative Environmental Sciences, Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Ten-Nou-Dai, Tsukuba, Ibaraki 305-8572, Japan. yukari@pe.ies.life.tsukuba.ac.jp | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | 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 | PMID:15530489 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 556 | ||
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Author | Izar, P.; Ferreira, R.G.; Sato, T. | ||||
Title | Describing the organization of dominance relationships by dominance-directed tree method | Type | Journal Article | ||
Year | 2006 | Publication | American journal of primatology | Abbreviated Journal | Am. J. Primatol. |
Volume | 68 | Issue | 2 | Pages | 189-207 |
Keywords | Animals; Cebus/physiology; *Models, Biological; *Social Dominance | ||||
Abstract | Methods to describe dominance hierarchies are a key tool in primatology studies. Most current methods are appropriate for analyzing linear and near-linear hierarchies; however, more complex structures are common in primate groups. We propose a method termed “dominance-directed tree.” This method is based on graph theory and set theory to analyze dominance relationships in social groups. The method constructs a transitive matrix by imposing transitivity to the dominance matrix and produces a graphical representation of the dominance relationships, which allows an easy visualization of the hierarchical position of the individuals, or subsets of individuals. The method is also able to detect partial and complete hierarchies, and to describe situations in which hierarchical and nonhierarchical principles operate. To illustrate the method, we apply a dominance tree analysis to artificial data and empirical data from a group of Cebus apella. | ||||
Address | Department of Experimental Psychology, University of Sao Paulo, Brazil. patrizar@usp.br | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0275-2565 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:16429416 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 723 | ||
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Author | Hamilton, W.D. | ||||
Title | Geometry for the selfish herd | Type | Journal Article | ||
Year | 1971 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
Volume | 31 | Issue | 2 | Pages | 295-311 |
Keywords | Animals; Anura; *Behavior, Animal; Breeding; Communication; Evolution; Fear; Metallurgy; *Models, Biological; Probability; Snakes; *Spatial Behavior | ||||
Abstract | This paper presents an antithesis to the view that gregarious behaviour is evolved through benefits to the population or species. Following Galton (1871) and Williams (1964) gregarious behaviour is considered as a form of cover-seeking in which each animal tries to reduce its chance of being caught by a predator. It is easy to see how pruning of marginal individuals can maintain centripetal instincts in already gregarious species; some evidence that marginal pruning actually occurs is summarized. Besides this, simply defined models are used to show that even in non-gregarious species selection is likely to favour individuals who stay close to others. Although not universal or unipotent, cover-seeking is a widespread and important element in animal aggregation, as the literature shows. Neglect of the idea has probably followed from a general disbelief that evolution can be dysgenic for a species. Nevertheless, selection theory provides no support for such disbelief in the case of species with outbreeding or unsubdivided populations. The model for two dimensions involves a complex problem in geometrical probability which has relevance also in metallurgy and communication science. Some empirical data on this, gathered from random number plots, is presented as of possible heuristic value. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | 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 | PMID:5104951 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 771 | ||
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Author | Tobin, T.; Combie, J.D. | ||||
Title | Performance testing in horses: a review of the role of simple behavioral models in the design of performance experiments | Type | Journal Article | ||
Year | 1982 | Publication | Journal of Veterinary Pharmacology and Therapeutics | Abbreviated Journal | J Vet Pharmacol Ther |
Volume | 5 | Issue | 2 | Pages | 105-118 |
Keywords | Analgesics, Opioid/pharmacology; Animals; Apomorphine/pharmacology; Behavior, Animal/*drug effects; Dose-Response Relationship, Drug; Fentanyl/pharmacology; Horses/*physiology; Methylphenidate/pharmacology; *Models, Biological; Motor Activity/drug effects | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Summary Language | Original Title | ||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0140-7783 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | PMID:6125601 | Approved | no | ||
Call Number | refbase @ user @ | Serial | 1957 | ||
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