Artifacts Caused by Leaf-Cutting Ants of the Genus Atta (Hymenoptera: Formicidae): Postmortem Bite Injuries and the Tearing of Clothes

Ants are one of the first insects to find an exposed cadaver and can be present during all stages of decomposition. Although these organisms are not commonly used in postmortem interval estimates, they are to be taken into account on criminal investigations involving human corpses, since they can leave bite marks that can be mistaken for antemortem or perimortem injuries, which could be misleading when ascertaining the occurrence of abuse or physical altercation during a crime. A few studies report the action of ants on human cadavers and even though leaf-cutting ants of the genus Atta are frequently encountered in succession studies that use animal carcasses, there are no records of these fungus-growing species on human corpses. Atta is a genus restricted to the New World, ranging from northern Argentina to southern United States and acts as one of the most conspicuous neotropical herbivores. In this study, we report three cases of violent death that illustrate the impact of ants, especially those of the genus Atta, in a forensic setting. We compare the patterns displayed by postmortem bite injuries caused by leaf-cutter ants and other common species with less robust mandibles. We also present the capability of Atta ants to create artifacts by cutting victim’s clothes in a crime scene, contributing to the knowledge of ant-mediated confounding factors in crime scene investigation.     

The case of Jeffrey Dahmer: sexual serial homicide from a neuropsychiatric developmental perspective

Sexual serial homicidal behavior has received considerable attention during the last three decades. Substantial progress has been made in the development of methods aimed at identifying and apprehending individuals who exhibit these behaviors. In spite of these advances, the origins of sexual serial killing behavior remain for the most part unknown. In this article we propose a biopsychosocial psychiatric model for understanding the origins of sexual serial homicidal behavior from both neuropsychiatric and developmental perspectives, using the case of convicted serial killer Jeffrey Dahmer as the focal point. We propose that his homicidal behavior was intrinsically associated with autistic spectrum psychopathology, specifically Asperger's disorder. The relationship of Asperger's disorder to other psychopathology and to his homicidal behavior is explored. We discuss potential implications of the proposed model for the future study of the causes of sexual serial homicidal crime.     

Infanticide: is its incidence among postneonatal infant deaths increasing?: an 18-year population-based analysis in California

The decline in the incidence of sudden infant death syndrome (SIDS) and recent recommendations regarding the differentiation of SIDS and child abuse has generated speculation that some cases of infanticide were misdiagnosed as SIDS. The aims of this study were to determine the change in incidences and proportions of postneonatal deaths from all causes, SIDS, and infanticide in California over an 18-year interval encompassing years before and after the Back to Sleep campaign. Selected postneonatal mortality data from 1981 through 1998 obtained from the California Department of Health Services were analyzed and graphically displayed. The total postneonatal mortality and incidence of SIDS deaths per 100,000 live births decreased 45% and 66%, respectively, during the study interval; the incidence of infanticide remained low. The ratio of infanticide to SIDS increased from 4.3 per 100 in 1981 to 10.2 per 100 in 1998. Infanticide deaths, as a percentage of the total number of postneonatal deaths, increased slightly from the first to the second half of the study interval but never rose above 3.2%. It is concluded that this increased percentage is due to a decrease in SIDS deaths and not to an actual increase in infanticide deaths.     

Allele frequencies of nine STR loci--D16S539, D7S820, D13S317, CSF1PO,TPOX, TH01, F13A01, FESFPS and vWA--in the population from Alagoas,northeastern Brazil

The polymorphism of nine STR loci has been studied in a sample of 598 individuals from the population of Alagoas, Northeastern Brazil. Determination of the allele frequencies as well as of several commonly used statistics in forensic and paternity testing were defined. The most polymorphic loci were TH01 and D7S317. The exact test demonstrated that the nine loci analyzed in the population have no deviation from Hardy-Weinberg equilibrium (P > 0.05).     

Y-chromosome variation in Rio de Janeiro,Brazil, population sample

Allele and haplotype frequencies of seven Y-chromosome STR loci, DYS 19, DYS388, DYS389I, DYS389II, DYS390, DYS391 and DYS392, were determined from 109 unrelated males in Rio de Janeiro, Brazil, sample population.