| |
Records |
Links  |
|
Author |
Axelrod, R.; Hamilton, W.D. |
|
| |
Title |
The evolution of cooperation |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Science |
Abbreviated Journal |
Science |
|
| |
Volume |
211 |
Issue |
4489 |
Pages |
1390-1396 |
|
| |
Keywords |
|
|
| |
Abstract |
Cooperation in organisms, whether bacteria or primates, has been a difficulty for evolutionary theory since Darwin. On the assumption that interactions between pairs of individuals occur on a probabilistic basis, a model is developed based on the concept of an evolutionarily stable strategy in the context of the Prisoner's Dilemma game. Deductions from the model, and the results of a computer tournament show how cooperation based on reciprocity can get started in an asocial world, can thrive while interacting with a wide range of other strategies, and can resist invasion once fully established. Potential applications include specific aspects of territoriality, mating, and disease. |
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
10.1126/science.7466396 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
4933 |
|
| 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 |
Barnard, C.J.; Sibly, R.M. |
|
| |
Title |
Producers and scroungers: A general model and its application to captive flocks of house sparrows |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
29 |
Issue |
2 |
Pages |
543-550 |
|
| |
Keywords |
|
|
| |
Abstract |
Many forms of interaction within and between species appear to be based on `scrounger' individuals or species exploiting a limited resource provided `producers'. A mathematical model is presented which shows whether or not scroungers are maintained in a group, depending on their frequency and the group size. Some of the predictions of the model were tested in captive flocks of house sparrows Passer domesticus L. Here the scroungers obtained most of their food (mealworms) by interaction and the producers found most of their food by actively foraging: the pay-off to each type was measured as mealworm capture rate. Neither type changed strategy opportunistically in response to instantaneous flock composition but, not surprisingly, scroungers fared better when one of more producers were present. However, scrougers did much worse than expected when greatly outnumbered by producers, perhaps because producers then found the available food very quickly. |
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
4200 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Roberts, J.; Hunter, M.L.; Kacelnik, A. |
|
| |
Title |
The ground effect and acoustic communication |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Animal Behaviour. |
Abbreviated Journal |
Anim. Behav. |
|
| |
Volume |
29 |
Issue |
2 |
Pages |
633-634 |
|
| |
Keywords |
|
|
| |
Abstract |
|
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
|
Serial |
2123 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bruns, E. |
|
| |
Title |
Estimation of the breeding value of stallions from the tournament performance of their offspring |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Livestock Production Science |
Abbreviated Journal |
|
|
| |
Volume |
8 |
Issue |
5 |
Pages |
465-473 |
|
| |
Keywords |
|
|
| |
Abstract |
Data from horse-riding competitions recorded in Germany in 1976 and 1977 have been analysed to estimate genetic parameters for performance traits of riding horses measured in dressage, jumping competitions and trials. The performance traits analysed were logarithmic earnings per start, relative place number, and place value. The results are the following. 1. (1) Heritability and repeatability estimates for performance in dressage shows are 0.2 and 0.4 respectively. Corresponding estimates for performance in jumping competitions are 20% less. No genetic differences are found between stallions for performance in trials.2. (2) A selection index for estimating the breeding value of stallions was constructed by using the repeated performances of their offspring in dressage and jumping shows. For this purpose, performance data for at least ten progeny should be available. The correlation between the breeding values estimated from the dressage and jumping performances of the same stallions was approximately zero.3. (3) Reliable progeny-testing requires that the assumptions of mating stallions at random, selecting progeny randomly, and distributing them equally across environmental effects be fulfilled.4. (4) The genetic use of breeding values of stallions estimated from the performance of their progeny is opposed by the prolongation of the generation interval. This can be partly overcome by sampling young stallions and making use of the test results for young progeny only. |
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
3968 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Kihara, H. |
|
| |
Title |
Comparison of the redox reactions of various types of cytochrome c with iron hexacyanides |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Biochimica et Biophysica Acta (BBA) – Bioenergetics |
Abbreviated Journal |
|
|
| |
Volume |
634 |
Issue |
|
Pages |
93-104 |
|
| |
Keywords |
Cytochrome c; Redox reaction; Iron hexacyanide; Temperature jump; Electron transfer |
|
| |
Abstract |
The dynamic behavior of various types of cytochromes c in the redox reaction with iron hexacyanides was studied using a temperature-jump method in order to elucidate the molecular mechanism of the redox reaction of cytochromes with their oxidoreductants. Transmittance after the temperature jump changed through a single exponential decay for all cytochromes investigated. Under a constant concentration of anion, the redox reaction of various types of cytochrome c with iron hexacyanides was analyzed according to the scheme: Ki=kt/k-i (i=1,2,3) where C(III) and C(II) are ferric and ferrous cytochromes, respectively, Fe(III) and Fe(II) are ferri- and ferrocyanides, respectively, C(III) [middle dot] Fe(II) is the ferricytochrome-ferrocyanide complex and C(II) [middle dot] Fe(III) is the ferrocytochrome-ferricyanide complex. When step B is slower than the other two steps A and C, τ-1 can be represented approximately as where the bar over the variables denotes the equilibrium value. In a large excess of ferrocyanide against cytochrome, we can estimate k2, k-2, K1 and K3 independently. In the case of horse cytochrome c at 18[degree sign]C in 0.1 M phosphate buffer at pH 7 with 0.3 M KNO3, the estimated parameters are k2 = 100 +/- 50 s-1, k-2 = (3.5 +/- 1.0) [middle dot] 103 s-1, K1 = 15 +/- 7 M-1 and K3 = (8.5 +/- 1.5) [middle dot] 10-4 M. From the same experiments for seven cytochromes (cytochrome c from horse, tuna, Candida krusei, Saccharomyces oviformis, Rhodospirillum rubrum cytochrome c2, Spirulina platensis cytochrome c-554 and Thermus thermophilus cytochrome c-552), the following results can be deduced. (1) Each parameter defined in the scheme above (k2, k-2, K1, K3) diverged beyond the error range. Above all, k2 values of cytochromes c-554 and c-552 are as large as 1 [middle dot] 104 s-1 and much larger than those for the other cytochromes (to 50 approx. 700 S-1). (2) The variance of k2K1 and k-2/K3 are relatively less than the variances of individual parameters (k2, k-2, K1 and K3), which suggests that the values of k2K1 and k-2/K3 have been conserved during the course of evolution. |
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
3980 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Heird, J.C.; Lennon, A.M.; Bell, R.W. |
|
| |
Title |
Effects of early experience on the learning ability of yearling horses |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Journal of Animal Science |
Abbreviated Journal |
J. Anim Sci. |
|
| |
Volume |
53 |
Issue |
5 |
Pages |
1204-1209 |
|
| |
Keywords |
Animals; Conditioning (Psychology); Female; *Handling (Psychology); Horses/*physiology; *Learning |
|
| |
Abstract |
Twenty-four yearling Quarter Horse fillies were divided into three groups (I) very limited handling, (II) intermediate handling and (III) extensive handling. At about 14 months of age, each horse was preconditioned for 2 weeks and then run in a simple place-learning T-maze test in which it had to locate its feed. Thirty trials were run daily for 20 days, with the location of the feed changed each day. To retire from the maze, a horse had to meet the criterion: 11 correct responses in 12 tries, with the last eight being consecutive. Horses in Group II required the fewest trials to reach criterion. These horses also learned more and had the highest percentage of correct responses (P less than .05). Mean trainability tended to predict learning ability; however, trainability and trials to criterion were not significantly correlated. Mean emotionality scores indicated a tendency for horses in the intermediately handled group to be less emotional than those in Group I or III. Results indicated that horses with an intermediate amount of handling scored higher on an intermediate test of learning. All handled horses scored higher on learning tests than those not handled. |
|
| |
Address |
|
|
| |
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 |
0021-8812 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
PMID:7319966 |
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
3577 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
McCall, C.A.; Potter, G.D.; Friend, T.H.; Ingram, R.S. |
|
| |
Title |
Learning abilities in yearling horses using the Hebb-Williams closed field maze |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
J. Anim. Sci. |
Abbreviated Journal |
J. Anim. Sci. |
|
| |
Volume |
53 |
Issue |
4 |
Pages |
928-933 |
|
| |
Keywords |
|
|
| |
Abstract |
|
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Cited By (since 1996): 9; Export Date: 24 October 2008 |
Approved |
no |
|
| |
Call Number |
Admin @ knut @ |
Serial |
4613 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
R. A. J. Taylor |
|
| |
Title |
The Behavioural Basis of Redistribution I. The Delta -Model Concept |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
The Journal of Animal Ecology |
Abbreviated Journal |
T. J. Anim. Ecol. |
|
| |
Volume |
50 |
Issue |
2 |
Pages |
573-586 |
|
| |
Keywords |
|
|
| |
Abstract |
(1) A conceptual model is developed in which spatial behaviour is density-dependent. The behaviour is classified as congregatory or migratory according to whether it results in movement towards or away from population concentrations. (2) Spatial behaviour is shown to result from both individual and population interactions. (3) The stability properties of the model are explored and it is shown how, under particular conditions, populations obeying the model have a population density regulating mechanism. (4) The similarity between the model and the potential energy curve of physics is noted, but it is emphasized that this is a behavioural not a physical model. |
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
refbase @ user @ |
Serial |
720 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Mace, G.M.; Harvey, P.H.; Clutton-Brock, T.H. |
|
| |
Title |
Brain size and ecology in small mammals |
Type |
Journal Article |
| |
Year |
1981 |
Publication |
Journal of Zoology |
Abbreviated Journal |
J Zool |
|
| |
Volume |
193 |
Issue |
3 |
Pages |
333-354 |
|
| |
Keywords |
|
|
| |
Abstract |
Relative brain size (measured as gross brain size after body size effects are removed) differs systematically between families of rodents, insectivores and lagomorphs. The Sciuridae have the largest relative brain size, the Soricidae and Bathyergidae the smallest. These results are discussed and compared with previous analyses of relative brain sizes among primates and bats. These differences complicate comparisons between relative brain size across phylogenetically diverse species and attempts to relate differences in relative brain size to ecological variables. To overcome these problems, best fit relationships were estimated for each family, and values for each genus were expressed as deviations from the lines of best fit. We refer to these values as Comparative Brain Size (CBS). Differences in CBS are related to differences in habitat type (forest-dwelling genera have larger CBS' than grassland forms), in diet (folivores have smaller CBS' than generalists or insectivores, frugivores and granivores), in zonation (arboreal genera have larger CBS' than terrestrial ones) and in activity timing (nocturnal genera have larger CBS' than dirurnal ones). However, these ecological categories are interrelated and, when the effects of other ecological differences are taken into account using analyses of variance, only the differences associated with diet, and possibly habitat remain. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Blackwell Publishing Ltd |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1469-7998 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
Equine Behaviour @ team @ |
Serial |
5455 |
|
| Permanent link to this record |
