2010年1月28日 星期四

生性大膽的胖頭鱥無論在野外或實驗室條件下都會對掠食者的存在穩定展現不害怕的氣魄, 然而大膽與害羞個體無法由大小雌雄有沒有寄生蟲來判別

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文獻來源: Pellegrini AFA, Wisenden BD, Sorensen PW. 2010. Bold minnows consistently approach danger in the field and lab in response to either chemical or visual indicators of predation risk. Behavioral Ecology and Sociobiology 64(3): 381-387.

Abstract
A behavioral syndrome is a suite of behaviors correlated across multiple social contexts. In this study, boldness in the face of predation risk was assessed twice in fish across two different sensory modalities in both the field and lab to ascertain the biological relevance and complexity of this attribute. Individual fathead minnows were captured from a natural field population using traps that either contained chemical alarm cues (conspecific skin extract) or control (well water) and their responses to the presence of predator behind a glass partition assessed in the laboratory. Although fewer fish were captured in alarm cue-labeled traps, these bold fish performed longer predator inspections than shy fish captured in control traps. Thus, a shy/bold behavioral syndrome was expressed consistently across field and lab settings in response to both chemical and visual indicators of danger. Shy and bold individuals did not differ in sex, body length, secondary sexual characteristics, or parasite load but were of more robust physical condition.