Kacelnik, A., & Houston, A. I. (1984). Some effects of energy costs on foraging strategies. Anim. Behav., 32(2), 609–614.
Abstract: We consider the effect of including energy costs on the optimal strategy for animals exploiting a depleting food resource. In the context of central place foraging this leads to the problem of what load size should be brought back to the central place. Two strategies are discussed: (i) maximize gross rate of energy delivery and (ii) maximize net rate of energy delivery. The optimal load size (or optimal patch time) for net maximizers is not always larger than for gross maximizers, as has been claimed. Instead, the difference in optimal load size has the same sign as the difference between metabolic rates of travelling and foraging. We point out that the influence of costs has not always been correctly incorporated in experimental tests of the theory.
|
Seyfarth, R. M., & Cheney, D. L. (1984). Grooming, alliances and reciprocal altruism in vervet monkeys. Nature, 308(5959), 541–543.
Abstract: Reciprocal altruism refers to the exchange of beneficial acts between individuals, in which the benefits to the recipient exceed the cost to the altruist. Theory predicts that cooperation among unrelated animals can occur whenever individuals encounter each other regularly and are capable of adjusting their cooperative behaviour according to experience. Although the potential for reciprocal altruism exists in many animal societies, most interactions occur between closely related individuals, and examples of reciprocity among non-kin are rare. The field experiments on vervet monkeys which we present here demonstrate that grooming between unrelated individuals increases the probability that they will subsequently attend to each others' solicitations for aid. Vervets appear to be more willing to aid unrelated individuals if those individuals have behaved affinitively toward them in the recent past. In contrast, recent grooming between close genetic relatives appears to have no effect on their willingness to respond to each other's solicitations for aid.
|
|
DUNCAN P et al,. (1984). Reduction of inbreeding in a natural herd of horses. Anim Beh av, 32, 520–527.
|
|
Mccort Wd,. (1984). Behavior of feral horses and ponies. J Anim Sci, 58, 493–499.
|
|
Boesch C, & Boesch H. (1984). Possible causes of sex differences in the use of natural hammers by wild chimpanzees. J. Hum. Evol., 13, 415.
|
|
Vogt H,. (1984). Quagga: DNA konserviert. Naturwiss Rdsch, 37, 327–328.
|
|
Kusunose R, S. H. (1984). The behavioral development of thouroughbred foals and the relationship between dams and foals. Jap J Zootechn Sci, 55, 263–271.
|
DUNCAN P et al,. (1984). On lactation and associated behaviour in natural herd of horses. Hans Klingels Equine Reference List, 32, 255–263.
Abstract: Developmental changes in time spent suckling and related mother-foal behaviour are described in an unmanaged herd of Camargue horses. Male foals spent about 40% more time suckling than females during the first 8 weeks. Body weight did not differ between the sexes but time-budgets did: males grazed less and were more active. If pregnant, the typical multiparous mare nursed her foals for 35–40 weeks, males and females alike, and weaned them 15 weeks before the next foaling. Primiparae lactated longer and weaned closer to the next foaling by 5 weeks. The mares played an active role in regulating the time spent suckling in early, and particularly in late lactation.
|
|
Wolski, K. (1984). Equine behaviour, patterns, types, and causes. Vet Technician, 5, 250–258.
|
|
Eisenmann V,. (1984). Sur quelques caractères adaptatifs du squelette d`Equus et leurs implications paléoécologiques Bull. Bull Mus natn Hist nat Paris, 6, 185–195.
|
