Vannatta J Trevor, Knowles Thomas, Minchella Dennis J, Gleichsner Alyssa M
Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907.
Department of Biological Sciences, SUNY Plattsburgh, 101 Broad Street, Plattsburgh, New York 12901.
J Parasitol. 2020 Feb;106(1):1-8.
The manipulation of host organisms by their parasites has captured the attention of ecologists, parasitologists, and the public. However, our knowledge of parasite behavior independent of a host is limited despite the far-reaching implications of parasite behavior. Parasite behaviors can help explain trematode community structure, the aggregation of parasites within host populations, and can potentially be harnessed in biocontrol measures. In this study, we used a simple choice chamber design to examine whether trematode parasites can detect the infection status of a potential host and avoid hosts infected with a competitively dominant species. Our results show that , a competitively subordinate species, can detect and avoid hosts infected with a competitively dominant parasite, . However, , despite showing a significant preference for snails infected with over uninfected snails, showed little ability to detect the infection status of the host or even the host's presence. We propose subordinate species may be under stronger selection to avoid dominant competitors whereas dominant competitors may be more strongly selected to find any suitable host, regardless of infection status. Previous research has focused on parasites distinguishing between 'host' and 'non-host', which does not fully capture the complexity of these interactions. However, the ability of subordinate parasites to determine the infection status of a host results in a consistent evolutionary advantage.
寄生虫对宿主生物体的操控引起了生态学家、寄生虫学家以及公众的关注。然而，尽管寄生虫行为具有深远影响，但我们对其独立于宿主的行为的了解却很有限。寄生虫行为有助于解释吸虫群落结构、寄生虫在宿主种群中的聚集情况，并且在生物防治措施中可能具有潜在用途。在本研究中，我们采用了一种简单的选择室设计，以检验吸虫寄生虫是否能够检测潜在宿主的感染状态，并避开感染了竞争优势物种的宿主。我们的结果表明，作为竞争劣势物种，能够检测并避开感染了竞争优势寄生虫的宿主。然而，尽管相较于未感染的蜗牛，对感染了的蜗牛表现出显著偏好，但几乎没有能力检测宿主的感染状态，甚至无法检测到宿主的存在。我们认为，劣势物种可能在更强的选择压力下以避开优势竞争者，而优势竞争者可能在更强的选择压力下寻找任何合适的宿主，无论其感染状态如何。以往的研究集中在寄生虫区分“宿主”和“非宿主”，这并未完全捕捉到这些相互作用的复杂性。然而，劣势寄生虫确定宿主感染状态的能力带来了持续的进化优势。
