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Searching Image In The Pigeon: A Test Of Three Hypothetical Mechanisms, Alan B. Bond, Donald A. Riley
Searching Image In The Pigeon: A Test Of Three Hypothetical Mechanisms, Alan B. Bond, Donald A. Riley
Papers in Behavior in Biological Sciences
The searching image hypothesis was originally proposed to account for the observation that animals selecting among disparate foods often consume an excess of the more common types. The hypothesis states that animals searching for a particular cryptic food item focus on visual features that are characteristic of that item, thereby facilitating its discrimination from the background. A change in stimulus discriminability is not, however, the only feasible explanation for the effect. One alternative is a simple change in response bias, an increased predisposition to respond to food-related stimuli. Another possible hypothesis derives from the fact that the amount of time …
Social Behavior And The Ontogeny Of Foraging In The Kea (Nestor Notabilis), Judy Diamond, Alan B. Bond
Social Behavior And The Ontogeny Of Foraging In The Kea (Nestor Notabilis), Judy Diamond, Alan B. Bond
Papers in Behavior in Biological Sciences
Kea are omnivorous parrots endemic to the high mountains of the South Island of New Zealand. Over a two-year period, we recorded quantitative behavioral data from 38 banded male kea foraging at a refuse dump outside Arthur's Pass National Park and analyzed the effects of social factors on the ontogeny of foraging. Members of the four distinguishable age classes — fledglings, juveniles, subadults, and adults — displayed characteristic differences in foraging ability and in the social behavior used to obtain access to resources. Adults performed most of the excavation that uncovered new food resources. Fledglings explored and manipulated objects almost …
Sexual Dimorphism In The Kea Nestor Notabilis, Alan B. Bond, Kerry-Jayne Wilson, Judy Diamond
Sexual Dimorphism In The Kea Nestor Notabilis, Alan B. Bond, Kerry-Jayne Wilson, Judy Diamond
Papers in Behavior in Biological Sciences
Morphological differences between the sexes in Keas Nestor notabilis were quantified from a sample of 86 sexed museum specimens, nine sexed zoo captives and 129 live, wild-caught birds. The results demonstrate that Kea are sexually dimorphic. Males are about 5% larger than females in linear measurements of body size and their upper bills are on average 12-14% longer, with a slightly larger radius of curvature. The dimorphism in bill size was statistically independent of the difference in overall body size, suggesting the possibility of intersexual differences in niche utilisation. Culmen length appears to be a useful means for distinguishing sexes …
Integrating Cognitive Ethology With Cognitive Psychology, Sonja I. Yoerg, Alan Kamil
Integrating Cognitive Ethology With Cognitive Psychology, Sonja I. Yoerg, Alan Kamil
Papers in Behavior in Biological Sciences
Cognitive ethology has been defined by Griffin (1978,1981, 1984) as the study of mental experiences in animals, restricting the domain of the field to phenomena thought to reveal intentionality, awareness, and conscious thinking. We argue that attempts to study these processes, while revealing impressive behavioral complexity, have proven unsuccessful in establishing the importance of mental experiences in determining animal behavior primarily because of the intractability of the problem. We suggest a different approach that draws upon the rich theory and sophisticated methodology of human and animal cognitive psychology while retaining an ecological and evolutionary perspective. Brief accounts of the conceptual …
Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne
Introgression Of Coyote Mitochondrial Dna Into Sympatric North American Gray Wolf Populations, Niles Lehman, Andrew Eisenhawer, Kimberly Hansen, L. David Mech, Rolf O. Peterson, Peter J. P. Gogan, Robert K. Wayne
United States Geological Survey, Northern Prairie Wildlife Research Center: Publications
Mitochondrial DNA (mtDNA) genotypes of gray wolves and coyotes from localities throughout North America were determined using restriction fragment length polymorphisms. Of the 13 genotypes found among the wolves, 7 are clearly of coyote origin, indicating that genetic transfer of coyote mtDNA into wolf populations has occurred through hybridization. The transfer of mtDNA appears unidirectional from coyotes into wolves because no coyotes sampled have a wolf-derived mtDNA genotype. Wolves possessing coyote-derived genotypes are confined to a contiguous geographic region in Minnesota, Ontario, and Quebec, and the frequency of coyote- type mtDNA in these wolf populations is high (> 500%). The …
Eumeces Septentrionalis (Prairie Skink): Piscivory., Louis A. Somma
Eumeces Septentrionalis (Prairie Skink): Piscivory., Louis A. Somma
Papers in Herpetology
The prairie skink is a North American lizard characterized by a diet that is primarily insectivorous (Breckenridge 1943. Amer. MidI. Nat. 29:591-606). Fish have not been previously recorded as a food item (reviewed in Somma and Cochran 1989. Great Basin Nat. 49:525-534). On 3 June 1990 between 0930 and 1030 h, six Eumeces septentrionalis (three gravid females, one male, and two juveniles) were captured from amongst riprap and beneath stone slabs on the earthen dam forming the windward shoreline of Burchard lake, Pawnee Co., Nebraska (T.12N., R.10E., Sec. 4). The three females and one juvenile were placed in the …