While incentive contrast has been reliably demonstrated in single-response situations, tests for contrast-of-choice behavior have invariably failed to obtain the effect. Three experiments were reported that eliminated features of prior methodology which can mask the effect. (Editor/RK)

This document consists of two separate papers. The first paper, "A Balanced Marine Aquarium" (Barbara Jayne Palko), discusses various aspects of a balanced marine aquarium. Information provided includes the basic and optional equipment needed to construct a balanced aquarium, preparations for setting up the aquarium, preparing the…

These selected readings are designed to supplement James Gillespie's "Modern Livestock and Poultry Production" (2nd edition) as the student reference for the advanced beef unit. The 15 lessons build on Agricultural Science I and II competencies. Topics of the 15 lessons are: importance of the beef enterprise; cost of beef production;…

This publication serves as a guide on insects for elementary school age children. The information is geared to answer the most commonly asked questions by children about insects (such as whether a given insect bites). Facts are also presented on how and where insects live, what they eat, and what eats them. The introductory chapter explains the…

The present research evaluated the refractorylike response decrement, as found in habituation of auditory evoked peripheral vasoconstriction in rabbits, to determine whether or not it represents a short-term habituation process distinct from effector fatigue or sensory adaptation. (Editor)

This field guide is designed to permit observers to identify the cetaceans (whales, dolphins, and porpoises) they see in western North Atlantic, including the Caribbean Sea, the Gulf of Mexico, and the coastal waters of the United States and Canada. The animals described are not grouped by scientific relationships but by similarities in appearance…

This study investigated the effects of a short period of severe protein malnutrition on subsequent growth and development in the squirrel monkey. A total of 12 newborn monkeys were fed a low protein diet from 2 to 8 weeks of age then rehabilitated by returning them to the 13 percent protein diet of the control group. Minimum amount of protein…

This ancient Cherokee story details an encounter the Indians had with a strange beast after they misused nature thereby learning to respect the Creator. (RTS)

Using rats and pigeons as subjects, the effects of varying amounts of reinforcement on the rate and temporal patterns of interim and terminal behaviors engendered by periodic feeding schedules were assessed in three experiments. (Author/KC)

Five experiments investigated the differential effects of shock punishment on nonconsummatory licking (dry licking) and lever pressing. Results support a motivationally based theory of punishment involving the role of incentive stimuli associated with the particular responses studied. (Editor/RK)

There are some important similarities between biological and societal evolution, but these similarities should not blind the enormous differences between them. Each system must be analyzed on its own merits and according to its own peculiar properties and principles. (Author/AM)

There is no clearly defined, universally accepted evolutionary theory that social anthropologists must accept. There has been great progress in the understanding of genetic mechanisms, but there are still major controversies. The most fundamental problem comes from postulating genes to account for behaviors. (Author/AM)

A review of play in nonhuman animals indicates that play increases with phylogenetic status, is important for mature social development in more advanced species, reflects intentional activity, and is essential for the development of tool-using strategies. (Author)

Describes the redwing blackbird, focusing on the period from March, when the redwings migrate to the northern United States to begin the breeding cycle, to September, when they start to flock for their migration south. Topics include physical characteristics, habitat, breeding, nest building, and migration. (JHZ)

Four-month-old rhesus monkeys were removed from their social group under three different conditions of perceptual isolation from their mothers and peers. Infant behavior was recorded and blood samples were obtained for analysis of plasma cortisol. Infants never showed signs of depression; their responses following separation were seen as attempts…