Pruett-Jones, S. (1992). Independent Versus Nonindependent Mate Choice: Do Females Copy Each Other? Am Nat, 140(6), 1000–1009.
Abstract: There is increasing evidence from both observational and experimental studies that females may copy each other's mating decisions. Female copying can be defined as a type of nonindependent choice in which the probability that a female chooses a given male increases if other females have chosen that male and decreases if they have not. The important characteristic of copying behavior that separates it from other similar processes is that the change in the probability of choice is strictly because of the actions of other females and not the consequences of those actions (e.g., a male's behavior changing as a result of successful matings). A gametheory model suggests that the adaptive significance of female copying may depend primarily on the ratio of the costs to the benefits of active mate choice. Copying behavior, and more generally conspecific cueing, may be important in many behavioral processes beyond mate choice.
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Novacek, M. J. (1992). Mammalian phylogeny: shaking the tree. Nature, 356(6365), 121–125.
Abstract: Recent palaeontological discoveries and the correspondence between molecular and morphological results provide fresh insight on the deep structure of mammalian phylogeny. This new wave of research, however, has yet to resolve some important issues.
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Dart, A. J., Snyder, J. R., Pascoe, J. R., Meagher, D. M., & Wilson, W. D. (1992). Prepurchase evaluation of horses: 134 cases (1988-1990). J Am Vet Med Assoc, 201(7), 1061–1067.
Abstract: To quantify some components of prepurchase evaluations in horses, records from 134 evaluations performed during a 2-year period were reviewed and the outcome was determined via telephone follow-up interview. Sixty-two percent of the prepurchase evaluations had been performed at the clinic and 38% had been performed in the field by the ambulatory service. All evaluations included physical and lameness examinations, whereas radiography (49%), endoscopy (15%), nerve blocking (5%), transrectal palpation (3%), hematologic analysis (2%), electrocardiography (2%), drug testing for analgesic agents (2%), and ultrasonography of the flexor tendons (1%) were not always performed. Fifty-nine percent of horses evaluated at the clinic were radiographed, compared with 33% of horses evaluated in the field (P less than 0.05). Thirty-seven percent of horses evaluated were judged serviceable for their intended use. Thirty-five percent of horses evaluated at the clinic were assessed to be serviceable, compared with 41% of those evaluated in the field (P less than 0.05). Horses used for pleasure riding (48%) tended to be considered serviceable more often than horses used for more athletic endeavors (3-day eventing, 33%; hunter/jumper, 24%; show, 31%; dressage, 30%). The most common basis for finding a horse unserviceable was lameness (88%).(ABSTRACT TRUNCATED AT 250 WORDS)
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Caraco, T., Kacelnik, A., Mesnick, N., & Smulewitz, M. (1992). Short-term rate maximization when rewards and delays covary. Anim. Behav., 44(Part 3), 441–447.
Abstract: In nature foragers must exploit resources that vary randomly in both the energy acquired per item (reward) and the time required to pursue, capture and process an item (delay). Furthermore, rewards and delays associated with particular resources may often covary significantly. An analytical model asks how variance-covariance levels for rewards and delays could influence choice of resources when lack of information or cognitive limitation implies that a consumer attempts to maximize its short-term rate of energy gain. Both greater expected reward and reduced expected delay clearly should enhance preference for a resource. The model predicts that increased delay variance and reduced reward-delay covariance should increase a forager's preference for a resource. A forager should be risk-averse towards reward variance when the reward-delay covariance is positive, but should become risk-prone towards reward variance when the reward-delay covariance is negative.
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