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Most pathogens threatening to cause extinction of a host species are maintained on one or more reservoir hosts, in addition to the species that is threatened by disease. Further, most conventional host--pathogen theory assumes that transmission is related to host density, and therefore a pathogen should become extinct before its sole host. Tasmanian devil facial tumor disease is a recently emerged infectious cancer that has led to massive population declines and grave concerns for the future persistence of this largest surviving marsupial carnivore. Here we report the results of mark--recapture studies at six sites and use these data to estimate epidemiological parameters critical to both accurately assessing the risk of extinction from this disease and effectively managing this disease threat. Three sites were monitored from before or close to the time of disease arrival, and at three others disease was well established when trapping began, in one site for at least 10 years. We found no evidence for sex-specific differences in disease prevalence and little evidence of consistent seasonal variation in the force of infection. At all sites, the disease was maintained at high levels of prevalence (>50% in 2-3-year-old animals), despite causing major population declines. We also provide the first estimates of the basic reproductive rate [R.sub.0] for this disease. Using a simple age-structured deterministic model, we show that our results are not consistent with transmission being proportional to the density of infected hosts but are consistent with frequency-dependent transmission. This conclusion is further supported by the observation that local disease prevalence in 2-3-year-olds still exceeds 50% at a site where population density has been reduced by up to 90% in the past 12 years. These findings lend considerable weight to concerns that this host-specific pathogen will cause the extinction of the Tasmanian devil. Our study highlights the importance of rapidly implementing monitoring programs to determine how transmission depends on host density and emphasizes the need for ongoing management strategies involving a disease-free 'insurance population,' along with ongoing field monitoring programs to confirm whether local population extinction occurs. Key words: basic reproductive number [R.sub.0]; conservation biology; extinction; facial tumor disease; pathogen transmission; Sarcophilus harrisii; Tasmanian devil.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.anbehav.2007.05.008 Byline: David L. Sinn, Samuel D. Gosling, Natalie A. Moltschaniwskyj Abstract: Animals often differ from one another in their willingness to take risks in a number of functional contexts related to fitness (e.g. mating, dispersal, and foraging behaviour). Although several studies have reported life history correlates and selective consequences of this variation in shy/bold behaviour, little attention has been paid to developmental processes resulting in shy/bold phenotypes. Here, we present a lifetime developmental study of shy/bold behaviour in dumpling squid, Euprymna tasmanica. Behaviour was measured in two test contexts, a threat and a feeding test, at five times across the entire life span. Across test contexts, shy/bold behaviour was not correlated at any age; while within a test context, individual shy/bold phenotypes were consistent both before and after sexual maturity. During sexual maturity, different phenotypes displayed different amounts of developmental variation; shyer animals were more plastic in feeding tests, while bolder animals were more plastic in threat ones. Our results suggest that for some animals shy/bold behaviour throughout development is uncorrelated across different contexts related to risk, while within a context, there may still be developmental constraints to changing shy/bold behaviour. This constraint within a functional context, however, may be phenotype-specific, with some phenotypes able to change more than others. These results indicate that a greater understanding of developmental pathways is needed to determine whether shy/bold phenotypes per se are the sole focus of selection. Differences in developmental plasticity between shy/bold phenotypes may also confer differential fitness in fluctuating environments. Author Affiliation: (a) School of Aquaculture, University of Tasmania, Australia (a ) School of Plant Science, University of Tasmania, Australia (a ) Department of Psychology, University of Texas, U.S.A. Article History: Received 24 November 2006; Revised 31 January 2007; Accepted 14 May 2007 Article Note: (miscellaneous) MS. number: 9188R

Personality traits are a major class of behavioral variation often observed within populations of animals. However, little is known of the integration between personality and an individual's underlying biology. To address this, the authors measured personality traits in squid (Euprymna tasmanica) in 2 contexts while also describing trait correlates with biological parameters. Four traits (shy avoidance-bold aggression, activity, bury persistence, and reactivity) were reliably measured; however, trait expression between contexts was not correlated and thus was context-specific. Trait variation was not a function of gender or of somatic or reproductive condition but was explained partially by a squid's sexual maturity and its size. Results are discussed in terms of the interplay between personality variation and resulting life history strategies in animals.

During their 3rd week of life, 73 Octopus bimaculoides were observed to test whether discrete behaviors could be grouped reliably to reflect dimensions of temperament. Frequencies of behaviors during Week 3 were subjected to principal-components analysis (PCA), resulting in 4 components (active engagement, arousal/readiness, aggression, and avoidance/disinterest) that explain 53% of the variance. Levels of temperamental traits were then evaluated for 37 octopuses using composite scores at 3 time points across the first 9 weeks of life. Profile analysis revealed significant change for the testing group as a whole in trait expression levels from Week 3 to Week 6. Results also suggest a significant effect of relatedness on developing temperamental profiles of octopuses. Discussion focuses on how results apply to the life history of O. bimaculoides and what temperament can reveal about adaptive individuality in a protostome.