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Full-Text Articles in Life Sciences

Vocal Learning In Grey Parrots: A Brief Review Of Perception, Production, And Cross-Species Comparisons, Irene M. Pepperberg Oct 2010

Vocal Learning In Grey Parrots: A Brief Review Of Perception, Production, And Cross-Species Comparisons, Irene M. Pepperberg

Sentience Collection

This chapter briefly reviews what is known—and what remains to be understood—about Grey parrot vocal learning. I review Greys’ physical capacities—issues of auditory perception and production—then discuss how these capacities are used in vocal learning and can be recruited for referential communication with humans. I discuss cross-species comparisons where applicable and conclude with a description of recent research that integrates issues of reference, production and perception.


Are Unfamiliar Neighbours Considered To Be Dear-Enemies?, Elodie Briefer, Fanny Rybak, Thierry Aubin Aug 2010

Are Unfamiliar Neighbours Considered To Be Dear-Enemies?, Elodie Briefer, Fanny Rybak, Thierry Aubin

Sentience Collection

Background: Discriminating threatening individuals from non-threatening ones allow territory owners to modulate their territorial responses according to the threat posed by each intruder. This ability reduces costs associated with territorial defence. Reduced aggression towards familiar adjacent neighbours, termed the dear-enemy effect, has been shown in numerous species. An important question that has never been investigated is whether territory owners perceive distant neighbours established in the same group as strangers because of their unfamiliarity, or as dear-enemies because of their group membership.

Methodology/Principal Findings: To investigate this question, we played back to male skylarks (Alauda arvensis) songs of adjacent neighbours, distant …


Capuchins (Cebus Apella) Can Solve A Means-End Problem, Anna M. Yocom, Sarah T. Boysen Aug 2010

Capuchins (Cebus Apella) Can Solve A Means-End Problem, Anna M. Yocom, Sarah T. Boysen

Sentience Collection

Three capuchin monkeys (Cebus apella) were tested on a 2-choice discrimination task designed to examine their knowledge of support, modeled after Hauser, Kralik, and Botto-Mahan’s (1999) experiments with tamarins. This task involved a choice between 2 pieces of cloth, including 1 with a food reward placed on its surface, and a second cloth with the food reward next to its surface. After reliably solving the basic problem, the capuchins were tested with various alternations of the original food reward and cloth. The capuchins were able to solve the initial task quickly, and generalize their knowledge to additional functional and nonfunctional …


Changes In Area Affect Figure–Ground Assignment In Pigeons, Leyre Castro, Olga F. Lazareva, Shaun P. Vecera, Edward A. Wasserman Mar 2010

Changes In Area Affect Figure–Ground Assignment In Pigeons, Leyre Castro, Olga F. Lazareva, Shaun P. Vecera, Edward A. Wasserman

Perception Collection

A critical cue for figure–ground assignment in humans is area: smaller regions are more likely to be perceived as figures than are larger regions. To see if pigeons are similarly sensitive to this cue, we trained birds to report whether a target appeared on a colored figure or on a differently colored background. The initial training figure was either smaller than (Experiments 1 and 2) or the same area as (Experiment 2) the background. After training, we increased or decreased the size of the figure. When the original training shape was smaller than the background, pigeons’ performance improved with smaller …


Behavior Of A Solitary Sociable Female Bottlenose Dolphin (Tursiops Truncatus) Off The Coast Of Kent, Southeast England, Sonja Eisfeld, Mark P. Simmonds, Laura R. Stansfield Jan 2010

Behavior Of A Solitary Sociable Female Bottlenose Dolphin (Tursiops Truncatus) Off The Coast Of Kent, Southeast England, Sonja Eisfeld, Mark P. Simmonds, Laura R. Stansfield

Ethology Collection

This article provides a report of the behavior of a solitary sociable dolphin studied on the southeast coast of England in 2007. This is the first study of its kind in which behavior of such a nonhuman animal was systematically studied. By the time of this study, this young female was highly interactive with people in the water. People accompanied the dolphin for 18.4% of the 100 hr of observation, and their presence changed her behavior. The study recorded 39 different behaviors; feeding and resting behaviors declined in frequency in the presence of people. In addition, the dolphin exhibited behavior …


Quality Prevails Over Identity In The Sexually Selected Vocalisations Of An Ageing Mammal, Elodie F. Briefer, Elisabetta Vannoni, Alan G. Mcelligott Jan 2010

Quality Prevails Over Identity In The Sexually Selected Vocalisations Of An Ageing Mammal, Elodie F. Briefer, Elisabetta Vannoni, Alan G. Mcelligott

Ethology Collection

Background: Male sexually selected vocalisations generally contain both individuality and quality cues that are crucial in intra- as well as inter-sexual communication. As individuality is a fixed feature whereas male phenotypic quality changes with age, individuality and quality cues may be subjected to different selection pressures over time. Individuality (for example, morphology of the vocal apparatus) and quality (for example, body size and dominance status) can both affect the vocal production mechanism, inducing the same components of vocalisations to convey both kinds of information. In this case, do quality-related changes to the acoustic structure of calls induce a modification of …


Vigilance And Antipredator Responses Of Caribbean Reef Squid, Jennifer A. Mather Jan 2010

Vigilance And Antipredator Responses Of Caribbean Reef Squid, Jennifer A. Mather

Sentience Collection

Antipredator responses, especially those of open-ocean squid, have been seldom studied in the natural environment. Sepioteuthis sepioidea, observed by snorkellers near the shore in early morning/late afternoon, produced an average of eight moves of over 1m per hour, apparently mostly antipredator behaviours. Close approaches by herbivorous parrotfish elicited no response in 74% of encounters; otherwise, squid produced agonistic zebra stripes or startle-mantle-dots skin patterns. Predatory bar jack fish caused flight but not zebra displays, and squid usually paled and fled quickly (66%) from snapper. The speed of approach was the best predictor for flight and display responses to snapper, …


Octopuses (Enteroctopus Dofleini) Recognize Individual Humans, Roland C. Anderson, Jennifer A. Mather, Mathieu Q. Monette, Stephanie R.M. Zimsen Jan 2010

Octopuses (Enteroctopus Dofleini) Recognize Individual Humans, Roland C. Anderson, Jennifer A. Mather, Mathieu Q. Monette, Stephanie R.M. Zimsen

Sentience Collection

This study exposed 8 Enteroctopus dofleini separately to 2 unfamiliar individual humans over a 2-week period under differing circumstances. One person consistently fed the octopuses and the other touched them with a bristly stick. Each human recorded octopus body patterns, behaviors, and respiration rates directly after each treatment. At the end of 2 weeks, a body pattern (a dark Eyebar) and 2 behaviors (reaching arms toward or away from the tester and funnel direction) were significantly different in response to the 2 humans. The respiration rate of the 4 larger octopuses changed significantly in response to the 2 treatments; …


Male Territoriality In A Social Sciurid, Cynomys Gunnisoni: What Do Patterns Of Paternity Tell Us?, J. L. Verdolin, C. N. Slobodchikoff Jan 2010

Male Territoriality In A Social Sciurid, Cynomys Gunnisoni: What Do Patterns Of Paternity Tell Us?, J. L. Verdolin, C. N. Slobodchikoff

Veterinary Science and Medicine Collection

In many social sciurids, male territoriality confers significant mating advantages. We evaluated resident male paternity in Gunnison’s prairie dogs (Cynomys gunnisoni), a colonial ground-dwelling sciurid, where males and females cooperatively defend territories. Contrary to findings reported for other social sciurids, our results show that territorial resident males do not gain significant reproductive advantages. Resident males sired the majority of offspring from their respective territories only 10.5% of the time. A single non-resident male sired equal or greater number of offspring than any single resident male 71.2% of the time. While adult males were more likely to sire a greater number …


Squid Dances: An Ethogram Of Postures And Actions Of Sepioteuthis Sepioidea Squid With A Muscular Hydrostatic System, Jennifer A. Mather, Ulrike Griebel, Ruth A. Byrne Jan 2010

Squid Dances: An Ethogram Of Postures And Actions Of Sepioteuthis Sepioidea Squid With A Muscular Hydrostatic System, Jennifer A. Mather, Ulrike Griebel, Ruth A. Byrne

Sentience Collection

A taxonomy of the movement possibilities for any species, within the constraints of its neural and skeletal systems, should be one of the foundations of the study of its behaviour. Caribbean reef squid, Sepioteuthis sepioidea, appear to have many degrees of freedom in their movement as they live in a three-dimensional habitat and have no fixed skeleton but rather a muscular hydrostatic one. Within this apparent lack of constraints, there are regularities and patterns of common occurrences that allow this article to describe an ethogram of the movements, postures and positions of squid. Squid have a combination of bent, …