A Descriptive Methodology for Studying the Ontogeny of Object Play and Breed Differences in Dogs (Canis lupus familiaris).

Play behavior is a prominent aspect of juvenile behavior for many animals, yet early development, especially play with objects, has received little attention. Our previous study on object play introduced our general methods, focusing on litter differences in the developmental trajectory of object play and toy preferences. Here, we present a detailed ethogram of more than 30 observed object play behaviors. We focus on breed differences in the development of play in the three following breeds: Welsh Terriers, Vizslas, and standard Poodles. Puppies were video recorded from 3 to 7 weeks of age at half-week intervals upon the introduction of a standard set of five toys into their home environments. Ten minutes of video from each session for each puppy were analyzed using the Noldus Observer XT program. Aside from analyzing individual behaviors, they were also grouped into three behavioral categories. These were behaviors that occurred only in a solitary context, only in a social context, or in both contexts. Solitary object play developed first, and social object play developed later across breeds. There was a significant three-way interaction between breed, developmental age, and the context in which play occurred. Pairwise comparisons within each breed, age, and context are discussed, but a prominent result is that the onset of many behaviors occurred later in Welsh Terriers compared to the other breeds.

No sympathy for the devil: attributing psychopathic traits to capital murderers also predicts support for executing them.

Mental health evidence concerning antisocial and psychopathic traits appears to be introduced frequently in capital murder trials in the United States to argue that defendants are a "continuing threat" to society and thus worthy of execution. Using a simulation design, the present research examined how layperson perceptions of the psychopathic traits exhibited by a capital defendant would impact their attitudes about whether he should receive a death sentence. Across three studies (total N = 362), ratings of a defendant's perceived level of psychopathy strongly predicted support for executing him. The vast majority of the predictive utility was attributable to interpersonal and affective traits historically associated with psychopathy rather than traits associated with a criminal and socially deviant lifestyle. A defendant's perceived lack of remorse in particular was influential, although perceptions of grandiose self-worth and a manipulative interpersonal style also contributed incrementally to support for a death sentence. These results highlight how attributions regarding socially undesirable personality traits can have a pronounced negative impact on layperson attitudes toward persons who are perceived to exhibit these characteristics.

Long-term retention of visual tasks by two species of emydid turtles, Pseudemys nelsoni and Trachemys scripta.

Long-lived species are expected to have long-term memory capabilities. In this study we tested nine Florida Red-bellied Cooters (Pseudemys nelsoni) on their retention for both a procedural food acquisition task and visual discrimination task learned in a previous experiment. The turtles were tested and retrained after two months, after another 7.5 months, and finally after 36 months of no interaction with the test apparatus during the intervening periods. Turtles retained memory for the choice task and needed little retraining throughout. Furthermore, in a different visual discrimination task, both P. nelsoni and Trachemys scripta turtles showed 100% retention after 3.5 months of no testing. Odor-controlled tests confirmed that turtles were using visual cues to solve the task. Thus, in a laboratory context turtles demonstrate long-term memory of visual discrimination tasks, which relates to apparent abilities in natural environments.

Turtles (Pseudemys nelsoni) learn about visual cues indicating food from experienced turtles.

We investigated whether turtles (Pseudemys nelsoni) could learn about a visual object cue to obtain food reinforcement by observing conspecifics that had learned the task. This study was designed with a three part task which, if completed by the observer turtles, would provide evidence of their abilities to learn from other turtles using stimulus enhancement, goal emulation, or copying. All four P. nelsoni turtles tested after observation of a trained demonstrator, whom they had direct access to during the demonstrator training trials, learned not only to follow another turtle to the stimulus indicating food, but also, in the absence of the demonstrator, to approach the correct stimulus regardless of spatial position. Therefore, all four P. nelsoni turtles tested showed evidence of stimulus enhancement learning. This is the first experimental study of social learning in any aquatic reptile demonstrating that they have the ability to learn from conspecifics.

Arsenic (+3 oxidation state) methyltransferase genotype affects steady-state distribution and clearance of arsenic in arsenate-treated mice.

Arsenic (+3 oxidation state) methyltransferase (As3mt) catalyzes formation of mono-, di-, and tri-methylated metabolites of inorganic arsenic. Distribution and retention of arsenic were compared in adult female As3mt knockout mice and wild-type C57BL/6 mice using a regimen in which mice received daily oral doses of 0.5mg of arsenic as arsenate per kilogram of body weight. Regardless of genotype, arsenic body burdens attained steady state after 10 daily doses. At steady state, arsenic body burdens in As3mt knockout mice were 16 to 20 times greater than in wild-type mice. During the post dosing clearance period, arsenic body burdens declined in As3mt knockout mice to ~35% and in wild-type mice to ~10% of steady-state levels. Urinary concentration of arsenic was significantly lower in As3mt knockout mice than in wild-type mice. At steady state, As3mt knockout mice had significantly higher fractions of the body burden of arsenic in liver, kidney, and urinary bladder than did wild-type mice. These organs and lung had significantly higher arsenic concentrations than did corresponding organs from wild-type mice. Inorganic arsenic was the predominant species in tissues of As3mt knockout mice; tissues from wild-type mice contained mixtures of inorganic arsenic and its methylated metabolites. Diminished capacity for arsenic methylation in As3mt knockout mice prolongs retention of inorganic arsenic in tissues and affects whole body clearance of arsenic. Altered retention and tissue tropism of arsenic in As3mt knockout mice could affect the toxic or carcinogenic effects associated with exposure to this metalloid or its methylated metabolites.

A critical review of objective personality inventories with sex offenders.

This review provides a critical analysis of the ability of multiscale inventories to distinguish between sex offender and nonoffender control groups, as well as to discriminate sex offenders from other types of offenders. In addition to expanding upon previous reviews that examined the utility of the Minnesota Multiphasic Personality Inventory (MMPI) with this population (e.g., Levin & Stava, 1987), the current review included studies that utilized other multiscale inventories commonly used in forensic practice (i.e., MMPI-2, Millon Clinical Multiaxial Inventory-III [MCMI-III], Personality Assessment Inventory) and, when possible, provides effect sizes to evaluate group differences. Based on the review, the various forms of the MMPI and MCMI are clearly the most widely used instruments in sex offender populations. The MMPI Pd scale has shown moderate to large effect sizes when distinguishing between sex offender and nonsex offender groups, but this relationship may be reflective of antisocial behavior in general rather than traits specific to sex offenders. Recommendations to standardize future research classification strategies and more effectively utilize these instruments when assessing sex offenders are also provided.

Training and long-term memory of a novel food acquisition task in a turtle (Pseudemys nelsoni).

We developed a shaping procedure for training Florida red-bellied cooters, Pseudemys nelsoni, to dislodge clear plastic bottles to obtain food pellets. The animals were then trained in a 2-choice problem to choose only the bottle containing pellets. All nine turtles learned the task of knocking over bottles for food. For the discrimination task, turtles chose the correct bottle 71% on average. After 2 months (82-84 days), and again after another 7.5 months (228 days) of no interaction with the bottles, turtles were retested and many retained both the response and the discrimination (mean success rates 77-81%), with significant savings in retraining all turtles. The turtles showed two basic response strategies, which changed across time for some individuals. This study demonstrates that turtles can learn and retain a novel skill in a laboratory context.

A novel S-adenosyl-L-methionine:arsenic(III) methyltransferase from rat liver cytosol.

S-Adenosyl-l-methionine (AdoMet):arsenic(III) methyltransferase, purified from liver cytosol of adult male Fischer 344 rats, catalyzes transfer of a methyl group from AdoMet to trivalent arsenicals producing methylated and dimethylated arsenicals. The kinetics of production of methylated arsenicals in reaction mixtures containing enzyme, AdoMet, dithiothreitol, glutathione (GSH), and arsenite are consistent with a scheme in which monomethylated arsenical produced from arsenite is the substrate for a second methylation reaction that yields dimethylated arsenical. The mRNA for this protein predicts a 369-amino acid residue protein (molecular mass 41056) that contains common methyltransferase sequence motifs. Its sequence is similar to Cyt19, a putative methyltransferase, expressed in human and mouse tissues. Reverse transcription-polymerase chain reaction detects S-adenosyl-l-methionine:arsenic(III) methyltransferase mRNA in rat tissues and in HepG2 cells, a human cell line that methylates arsenite and methylarsonous acid. S-Adenosyl-l-methionine:arsenic(III) methyltransferase mRNA is not detected in UROtsa cells, an immortalized human urothelial cell line that does not methylate arsenite. Because methylation of arsenic is a critical feature of its metabolism, characterization of this enzyme will improve our understanding of this metalloid's metabolism and its actions as a toxin and a carcinogen.