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There is robust experimental evidence for contagious yawning, yet observational studies of naturalistic behavior have been fewer. Without data from real-world behavior, researchers have questioned the existence of contagious yawning and made assumptions about some parameters (e.g., the duration of the effect). We observed contagious yawning in chimpanzees to confirm/disconfirm its existence in the behavioral repertoire of this species, and if present, provide some of the missing descriptives. We recorded yawns on an all-occurrence basis from 18 captive-reared chimpanzees at the Los Angeles Zoo. We recorded identity, time, and individuals who could have been affected. We calculated a threshold for contagion by taking the mean and adding 1.96 standard deviations, constructing a response curve. Across multiple measures we see a consistent pattern in which there is a strong effect of contagion for 1.5 minutes, a less strong but still significant effect lasting up to 3.5 minutes in some measures, and no evidence of contagion beyond 3.5 minutes. From the time stamp on each yawn we were able to rule out temporal synchrony as an alternative hypothesis. Thus, contagious yawning appears to be a natural phenomenon in chimpanzees lending support to the myriad experimental and observational studies to date.

It has been speculated that the oral flora of the Komodo dragon (Varanus komodoensis) exerts a lethal effect on its prey; yet, scant information about their specific oral flora bacteriology, especially anaerobes, exists. Consequently, the aerobic and anaerobic oral bacteriology of 16 captive Komodo dragons (10 adults and six neonates), aged 2-17 yr for adults and 7-10 days for neonates, from three U.S. zoos were studied. Saliva and gingival samples were collected by zoo personnel, inoculated into anaerobic transport media, and delivered by courier to a reference laboratory. Samples were cultured for aerobes and anaerobes. Strains were identified by standard methods and 16S rRNA gene sequencing when required. The oral flora consisted of 39 aerobic and 21 anaerobic species, with some variation by zoo. Adult dragons grew 128 isolates, including 37 aerobic gram-negative rods (one to eight per specimen), especially Enterobacteriaceae; 50 aerobic gram-positive bacteria (two to nine per specimen), especially Staphylococcus sciuri and Enterococcusfaecalis, present in eight of 10 and nine of 10 dragons, respectively; and 41 anaerobes (one to six per specimen), especially clostridia. All hatchlings grew aerobes but none grew anaerobes. No virulent species were isolated. As with other carnivores, captive Komodo oral flora is simply reflective of the gut and skin flora of their recent meals and environment and is unlikely to cause rapid fatal infection.

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1982. Functions of female aggression during the pupping and mating season of grey seals, Halichoerus grypus (Fabricius). Can. J . Zool . 60: 2270-2278.Aggression of female grey seals Halichoerus grypus toward conspecifics was studied during the pupping and mating season on Sable Island, N.S. The responses of 65 individually identified females with pups toward known males and females were recorded throughout each female's stage of lactation. Female aggression varied both quantitatively and qualitatively as a function of the sex of an approaching animal. Males were threatened more often than females even though females outnumbered males. The likelihood of females threatening other females was affected by the location of the threatening female's pup, but aggression towards males was not affected by the pup's position. Females responded aggressively less often in the second half of lactation, when both weaning of the pup and oestrus occur, than in the first half. 'They were also more likely to threaten transient males than tenured males. However, a male approaching or mounting a female, whatever his status, was more likely to be challenged by another male if the female threatened him than if she did not. These challenges generally interrupted a male's approach or mount and hence a potential copulation. The results are consistent with the hypothesis that female aggression during the lactation period helps to protect the pup and increases the likelihood that a female mates with a dominant male. This latter function may be viewed as a form of mate choice. BONESS, D. J., S. S. ANDERSON et C. R. Cox. 1982. Functions of female aggression during the pupping and mating season of grey seals, Halichoerus grypus (Fabricius). Can. J . Zool. 60: 2270-2278.L'aggressivitC des femelles du phoque gris Halichoerus grypus a l'egard des autres phoques de la mkme esp2ce a Ct C CtudiCe durant la saison des amours et l'kpoque d'elevage des petits, a Sable Island en Nouvelle-Ecosse. La reaction de 65 femelles avec des petits a l'egard de miles et de femelles reconnaissables a Ct C enregistrke durant la phase de lactation de chacune d'elles. L'aggressivitC des femelles varie quantitativement et qualitativement en fonction du sexe de l'intrus. Les miles sont menacCs plus souvent que les femelles, mkme si les femelles sont plus nombreuses. La probabilite qu'une femelle menace d'autres femelles est affectCe par la proximitC de son petit, mais l'agressivitk envers les miles n'est pas affectCe par la position du petit. Les femelles sont agressives moins souvent durant la seconde moitiC de la lactation, au moment du sevrage et de l'oestrus. Elles sont egalement plus susceptibles de menacer des miles de passage que des miles rksidants. Cependant, un mile qui s'approche de la femelle ou la saillit, quel que soit son statut, est plus susceptible d'ktre dCfiC par un autre mile lorsque le femelle est agressive que lorsqu'elle ne l'est pas. Ces dCfis interrompent gCnCralement l'approche d'un mile ou sa saillie et coupent donc court a la copulation. I1 s...

Estrogen hormones play critical roles in the regulation of many tissue functions. The effects of estrogens are primarily mediated by the estrogen receptors (ER) α and β. ERs are ligand-activated transcription factors that regulate a complex array of genomic events that orchestrate cellular growth, differentiation and death. Although many factors contribute to their etiology, estrogens are thought to be the primary agents for the development and/or progression of target tissue malignancies. Many of the current modalities for the treatment of estrogen target tissue malignancies are based on agents with diverse pharmacology that alter or prevent ER functions by acting as estrogen competitors. Although these compounds have been successfully used in clinical settings, the efficacy of treatment shows variability. An increasing body of evidence implicates ERα polymorphisms as one of the contributory factors for differential responses to estrogen competitors. This review aims to highlight the recent findings on polymorphisms of the lately identified ERβ in order to provide a functional perspective with potential pharmacogenomic implications.

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