Concept Attribution in Nonhuman Animals: Theoretical and Methodological Problems in Ascribing Complex Mental Processes

The demise of behaviorism has made ethologists more willing to ascribe mental states to animals. However, a methodology that can avoid the charge of excessive anthropomorphism is needed. We describe a series of experiments that could help determine whether the behavior of nonhuman animals towards dead conspecifics is concept mediated. These experiments form the basis of a general point. The behavior of some animals is clearly guided by complex mental processes. The techniques developed by comparative psychologists and behavioral ecologists are able to provide us with the tools to critically evaluate hypotheses concerning the continuity between human minds and animal minds.Psycholog

Variation in Maternal Responsiveness in Free-Ranging Vervet Monkeys: A Response to Infant Mortality Risk?

Psycholog

The Evolution of Nonhuman Primate Vocalizations: Effects of Phylogeny, Body Weight, and Social Context

E. S. Morton proposed that, in birds and mammals, individuals tend to produce low-frequency atonal vocalizations in highly aggressive situations, whereas they typically produce high-frequency tonal vocalizations during nonaggressive or fearful situations. This hypothesis, referred to as the "motivation-structural (MS) rules," is based on two assumptions: the frequency of a vocalization is negatively correlated with body weight, and large animals are dominant over smaller animals, and thus aggressive vocalizations tend to have a lower pitch than fearful vocalizations. The relationship between body weight and frequency is examined using data on 36 nonhuman primate species representing 23 genera and 474 vocalizations. Results show that there is a statistically significant negative correlation between body weight and frequency: larger species produce relatively lower-pitched vocalizations than smaller species. A test of Morton's MS rules provided overall support for the predicted relationship between motivational state and frequency (i.e., high-frequency calls were produced by fearful individuals, and low-frequency calls were produced by aggressive individuals) but no support for the expected relationship between motivational state and tonality. However, the motivational state-frequency pairing was confounded by the fact that some taxonomic groups (Platyrrhini and Catarrhini) showed a much stronger level of association than other groups (Prosimii and Hominoidea). In summary, therefore, the nonhuman primate data provide only partial support for MS rules. At least three factors may have influenced the outcome of the current test. First, in some species, motivational state may be more closely associated with other acoustic parameters than absolute frequency and tonality. Second, the acoustic structure of nonhuman primate vocalizations is, at least in some cases, more closely associated with an external referent than with the caller's internal state. And third, features of the species-typical habitat have had direct selective effects on signal structure, optimizing for effective propagation through the environment.Psycholog

The Neurophysiology of Functionally Meaningful Categories: Macaque Ventrolateral Prefrontal Cortex Plays a Critical Role in Spontaneous Categorization of Species-Specific Vocalizations

Neurophysiological studies in nonhuman primates have demonstrated that the prefrontal cortex (PFC) plays a critical role in the acquisition of learned categories following training. What is presently unclear is whether this cortical area also plays a role in spontaneous recognition and discrimination of natural categories. Here, we explore this possibility by recording from neurons in the PFC while rhesus listen to species-specific vocalizations that vary in terms of their social function and acoustic morphology. We found that ventral prefrontal cortex (vPFC) activity, on average, did not differentiate between food calls that were associated with the same functional category, despite having different acoustic properties. In contrast, vPFC activity differentiated between food calls associated with different functional classes and specifically, information about the quality and motivational value of the food. These results suggest that the vPFC is involved in the categorization of socially meaningful signals, thereby both extending its previously conceived role in the acquisition of learned categories and showing the significance of using natural categorical distinctions in the study of neural mechanisms.Psycholog

Visual Representation in the Wild: How Rhesus Monkeys Parse Objects

Visual object representation was studied in free-ranging rhesus monkeys. To facilitate comparison with humans, and to provide a new tool for neurophysiologists, we used a looking time procedure originally developed for studies of human infants. Monkeys' looking times were measured to displays with one or two distinct objects, separated or together, stationary or moving. Results indicate that rhesus monkeys used featural information to parse the displays into distinct objects, and they found events in which distinct objects moved together more novel or unnatural than events in which distinct objects moved separately. These findings show both common-alities and contrasts with those obtained from human infants. We discuss their implications for the development and neural mechanisms of higher-level vision.Psycholog

General Intelligence in Another Primate: Individual Differences across Cognitive Task Performance in a New World Monkey (Saguinus oedipus)

Background: Individual differences in human cognitive abilities show consistently positive correlations across diverse domains, providing the basis for the trait of ‘‘general intelligence’ ’ (g). At present, little is known about the evolution of g, in part because most comparative studies focus on rodents or on differences across higher-level taxa. What is needed, therefore, are experiments targeting nonhuman primates, focusing on individual differences within a single species, using a broad battery of tasks. To this end, we administered a large battery of tasks, representing a broad range of cognitive domains, to a population of captive cotton-top tamarin monkeys (Saguinus oedipus). Methodology and Results: Using a Bayesian latent variable model, we show that the pattern of correlations among tasks is consistent with the existence of a general factor accounting for a small but significant proportion of the variance in each task (the lower bounds of 95 % Bayesian credibility intervals for correlations between g and task performance all exceed 0.12). Conclusion: Individual differences in cognitive abilities within at least one other primate species can be characterized by a general intelligence factor, supporting the hypothesis that important aspects of human cognitive function most likel

The Ursinus Weekly, March 25, 1971

Pettit reconsiders open dorm issue; USGA sets seven • Crime on campus continues; Checks, calculators copped • State of our prisons: Prison wardens defend merits of penal system • Editorial: Communications gap • Focus: Daphne Kline • Letters to the editor: Flak on Fred Flott; Haircut scholarships; Borish letter; Do-nothing air-heads; Sacred dormitories; Pettit praised • Movie critic: Friday night movies • Bloody good show • Grapplers finish winners; Ursinus\u27 big ten sighted • Delaware hosts female hoopmen • Tennis squad set; Jacob seeded 1st • Schaal honored; Named all starhttps://digitalcommons.ursinus.edu/weekly/1142/thumbnail.jp

The Ursinus Weekly, November 21, 1969

250,000 march on Washington to protest Nixon\u27s Viet War effort: 1965 Ursinus graduate leads Moratorium parade in US Air Force attire • 3 frosh injured in auto accident • Pre Med Convention tours Temple U. medical school • Ecumenism experiment now underway at U.C. • Editorials: The thrill of victory; When will it end? • Focus: Tom Branca • Liberate the nut • Letters to the editor: Campus Chest; Gripe; Never ending; Change; Mr. Faaet • Faculty portrait: F. Donald Zucker • Equality • Administration answers: Freedom of assembly • Coffee house conquers • Spotlight: Collegeville cop • I am curious (Morris) shocks Ursinus audience • Contemplations: Red neck kit • Security system • Hitch-hiking Bear Harriers victorious, finish dual meet season with 11-1 mark • Bearettes all make All-College • Gridders best since 1931 • Bears should be MAC champs • Dickinson edged by UC 21-20 • Centennial Football Day at Ursinushttps://digitalcommons.ursinus.edu/weekly/1152/thumbnail.jp

The Ursinus Weekly, May 28, 1970

Alan Gold, Weekly win press awards • Carol Haas, Ed Leinbach win in ISC • Brooks Hays selected speaker at graduation for 289 UC seniors • 1970 C.C.C. promises new approach to frosh • Three profs hired • Students pass Bill; Negotiations ensue • Editorial: Year of involvement • Focus: Larry Saunders • Letters to the editor: Publicly passionate; Maples patriots; Girl ratings • Eight faculty leave Ursinus • Students, administration, Board members discuss students rights at Skytop • Woodstock arrives on screen • Wind blown • From the other side: An exercise in contradiction • Contemplations: An apology • Summer reading program • 300 fete Eleanor Snell; Former Snellbelles present • Batmen finish dismal season; Outlook excellent for 1971 • Win over Albright caps tennis season • Cricket victory • A very good year for U.C. athletics • In the wake of Earth Day • Ursinus moviemakers explore daring field • Protest • Octogenarians get with ithttps://digitalcommons.ursinus.edu/weekly/1161/thumbnail.jp

The Ursinus Weekly, April 17, 1970

Administration deals USGA policy slap • Earth Day planned April 22: Grass-roots pollution fight • 1970 UC Campus Chest attempts $3,000 goal • Youngbloods, MagMen appearing on April 23 • Editorial: Student Bill of Rights • Focus: Alice Johnson • Faculty portrait: Philip J. Rappoccio • Greener ginkgo trees • Contemplations: Bill of Rights • Committee report: UC Student Union • Chapter scholars named • From the other side: Heaven on earth? • Letters to the editor: Amico speaks; Arts Festival; Underground; Weekly; Student Union? • Bears battle Mules in season\u27s opener • Snell honored on May 22nd • Returning Bearettes bolster spring teams • U.C. netmen steal moral victory over Swarthmore • Bear trackmen whip everybody on cindershttps://digitalcommons.ursinus.edu/weekly/1158/thumbnail.jp