Recent progress in mouse genetics has led to an increased interest in developing procedures for assessing mouse behavior, but relatively few of the behavioral procedures developed involve positively reinforced operant behavior. When operant methods are used, nose poking, not lever pressing, is the target response. In the current study differential…

The development of large-scale livestock facilities has become a controversial issue in many regions of the U.S. in recent years. In this research, rural-urban differences in familiarity and concern about large-scale livestock facilities among Ohioans is examined as well as the relationship of social distance from agriculture and trust in risk…

This paper develops a mathematical model for the nonselective harvesting of a prey-predator system in which both the prey and the predator obey the Gompertz law of growth and some prey avoid predation by hiding. The steady states of the system are determined, and the dynamical behaviour of both species is examined. The possibility of existence of…

Three pigeons were trained to discriminate among 5 mg/kg pentobarbital, 2 mg/kg amphetamine, a combination of these two drugs at these doses, and saline using a four-choice procedure (amphetamine--pentobarbital group). Three other pigeons were trained to discriminate among 5 mg/kg morphine, 2 mg/kg methamphetamine, a combination of these two drugs…

Pigeons' choosing between fixed-interval and random-interval schedules of reinforcement was investigated in three experiments using a discrete-trial procedure. In all three experiments, the random-interval schedule was generated by sampling a probability distribution at an interval (and in multiples of the interval) equal to that of the…

Our research addressed the question of whether sensitivity to relative reinforcer magnitude in concurrent chains depends on the distribution of reinforcer delays when the terminal-link schedules are equal. In Experiment 1, 12 pigeons responded in a two-component procedure. In both components, the initial links were concurrent variable-interval 40…

The present experiment investigated whether rats formed emergent, untrained stimulus relations in many-to-one matching-to-sample discriminations. In Phase 1, rats were trained to match two samples (triangle and horizontal stripes) to a common comparison (horizontal stripes) and two additional samples (circle or vertical stripes) to another…

Birds have an appealing beauty and a wonderful sense of adaptation to environment. A study was conducted to examine the adaptation patterns of birds in regard to the surroundings.

The effect of a visual warning signal (1.0-6.5s random foreperiod, FP) on the latency of voluntary (hand-grip) and reflexive (startle-eyeblink) reactions was investigated in Parkinson's disease (PD) patients and in young and aged control subjects. Equivalent FP effects on blink were observed across groups. By contrast, FP effects diverged for…

After rats were conditioned to prefer a flavor (CS+) paired with sucrose over another flavor (CS-) paired with saccharin, this conditioned flavor preference was extinguished by presenting the CS+ flavor without sucrose. These results were replicated in a second experiment in which spontaneous recovery of the extinguished flavor preference was…

Previous experiments have demonstrated that the simultaneous presentation of independently established discriminative stimuli can control rates of operant responding substantially higher than the rates occasioned by the individual stimuli. This "additive summation" phenomenon has been shown with a variety of different reinforcers (e.g., food,…

Two experiments with pigeons investigated the effects of contingencies between interresponse times (IRTs) and the transitions between the components of 2- and 4-component chained schedules (Experiments 1 and 2, respectively). The probability of component transitions varied directly with the most recent (Lag 0) IRT in some experimental conditions…

This article presents a tentatively "balanced" view (i.e., midway between lean and rich interpretations) of pointing behavior in infants and apes, based upon the notion of intentional reading of behavior without simultaneous attribution of unobservable mental states. This can account for the complexity of infant pointing without attributing…

This article examines problems that may arise when addressing liability resulting from the genetic modification of microbes, animals, and plants. More specifically, it evaluates how uncertainties relating to the outcomes of these biotechnological innovations affect--or may affect--the courts' application of the reasonable foreseeability…

In this article, we concentrate upon the lifeworld resources that comprise the funds of knowledge for children living in a rural community in the southeastern United States. Through interview conversations with a group of third grade children, we identified three lifeworld resources--interdependence, garbage dumping, and feral dogs--that rural…