This paper presents compelling, anecdotal evidence of severe population declines in five predator species, Dasyurus hallucatus, Varanus gouldii, V. mertensi, V. panoptes, and V. timorensis similis, in almost immediate response to Cane Toad colonization of their habitat in three widely distributed areas of northern Queensland. Furthermore, risk assessment of all quoll and monitor taxa whose distributions overlap the potential distribution of the Cane Toad in Australia (Sutherst et al. 1996), indicates that at the continental scale, three of the four quoll taxa and eight of the 20 monitor species examined are at high risk of severe population declines following Cane Toad colonization. One quoll taxon and seven monitor species are at moderate risk and five monitor species are at low risk. The definition of the threat which Cane Toads pose to native predators has received very little research attention, and fundamental questions including; which predator species are most at risk (testing of the risk assessment hypotheses presented here), the extent of these risks (is there a need to manage Cane Toad impacts upon predators?), and the contexts of intraspecific variation in relative extinction risk (for example, interactions of extinction risk with predator and Cane Toad population demography, climate, landscape, and land use), need to be assessed. Assuming that Cane Toads are found to have an impact across a range of taxa and landscapes (which I propose to be likely), management of the impact of this species on predators can be approached from two not necessarily exclusive directions; management of Cane Toad populations and management of predator populations, through both population and habitat management. At this stage, however, management from either viewpoint is constrained by a lack of published information relevant to autecology and fine scale distribution of predators.

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Hamate-pisiform coalition is characterized by the abnormal union of the pisiform bone and hamulus of the hamate. Because most reported cases are isolated, and literature on the subject is sparse, relatively little is known about this condition and its clinical significance. The purpose of this report is to discuss the occurrence, morphology, and frequency of hamate-pisiform coalition identified in a skeletal sample of native South Africans, and to conduct a metaanalysis of all known cases in order to clarify the sex distribution, laterality, form, and clinical significance of this condition. Five new cases (three male, two female) of hamate-pisiform coalition were identified in 527 native South Africans. Results indicate that hamate-pisiform coalition is infrequent (0.76%) but may be more likely encountered in individuals of African ancestry. Morphologically, non-osseous examples ranged in appearance from minor expressions involving pitting of an expanded hamulus base, to a variably pitted articulation between an elongated pisiform and hamulus. Osseous union between the two bones tends to extend beyond the hamulus base to adjacent areas of the hamate. Cases involving osseous union appear predisposed to fracture while ulnar neuropathy is significantly more frequent in individuals exhibiting non-osseous coalition. As both non-osseous and osseous cases can have clinical significance, awareness of the variable manifestations of this condition is necessary for hand specialists. A simplified classification system is suggested to more consistently characterize carpal coalitions.

KEY WORDSeastern gorilla biogeography; founder effect; genetic bottleneck; osseous and non-osseous coalitions; rare skeletal traits ABSTRACT Gorillas living in western central Africa (Gorilla gorilla) are morphologically and genetically distinguishable from those living in eastern central Africa (Gorilla beringei). Genomic analyses show eastern gorillas experienced a significant reduction in population size during the Pleistocene subsequent to geographical isolation from their western counterparts. However, how these results relate more specifically to the recent biogeographical and evolutionary history of eastern gorillas remains poorly understood. Here we show that two rare morphological traits are present in the hands and feet of both eastern gorilla subspecies at strikingly high frequencies (>60% in G. b. graueri; 28% in G. b. beringei) in comparison with western gorillas (<1%). The intrageneric distribution of these rare traits suggests that they became common among eastern gorillas after diverging from their western relatives during the early to middle Pleistocene. The extremely high frequencies observed among grauer gorillas-which currently occupy a geographic range more than ten times the size of that of mountain gorillas-imply that grauers originated relatively recently from a small founding population of eastern gorillas. Current paleoenvironmental, geological, and biogeographical evidence supports the hypothesis that a small group of eastern gorillas likely dispersed westward from the Virungas into present-day grauer range in the highlands just north of Lake Kivu, either immediately before or directly after the Younger Dryas interval. We propose that as the lowland forests of central Africa expanded rapidly during the early Holocene, they became connected with the expanding highland forests along the Albertine Rift and enabled the descendants of this small group to widely disperse. The descendant populations significantly expanded their geographic range and population numbers relative to the gorillas of the Virunga Mountains and the BwindiImpenetrable Forest, ultimately resulting in the grauer gorilla subspecies recognized today. This founder-effect hypothesis offers some optimism for modern conservation efforts to save critically endangered eastern gorillas from extinction. Am J Phys Anthropol 159:S4-S18,

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