为什么要外寄生虫？

Ectoparasites are organisms that live on the external surface of an organism (the host), from which they obtain their sustenance. The inflicted harm on the host can range from being a mere nuisance to life-threatening health conditions. Ectoparasite biology and host dependence is highly diverse. Some ectoparasites, such as lice, are permanent parasites that are highly dependent on a single host for survival and show a high species specificity, whereas others, for example ticks, only form temporary relations with their hosts and are more general in their choice of food source. Feeding on several hosts can lead to pathogen transmission between individuals, within one species, but also between wildlife, livestock and humans and therefore attracts particular attention.

为什么要狐猴？

夜间mouse lemurs是世界上最小的灵长类动物，是马达加斯加岛特有的，并且已成为保护的旗舰物种。面对贫困，政治不稳定，人口增长，并因此，人类侵占野生动植物栖息地，小鼠狐猴的自然分布范围不断下降，当前认可的24种物种中的大多数被IUCN RED列表列为危险。

Parasites and hosts have co-evolved for millions of years and may exist in a delicate balance with each other. Different factors, such as climate or host behavior are known to influence parasite intensity and mechanisms of adaption and evasion are pushing and pulling on either side. If this balance is disturbed, the negative effect of parasites may not be limited to the infected individual, but reduced survival and reduced reproduction can lead to severe effects on a population level. Therefore, parasitic infections have become a major concern in conservation biology.

我们的国际米兰national interdisciplinary German-Malagasy research team with experts from parasitology and zoology investigated ectoparasite communities of twoMicrocebusspecies (the Grey Mouse LemurMicrocebus murinus和the Golden-Brown Mouse Lemur,M. ravelobensis），在其自然栖息地以了解其当前的非洲岩石多样性，可能对狐猴健康和物种之间疾病传播的潜在截距的潜在截距。

The Grey and the Golden-Brown Mouse Lemur have been studied for over 20 years in theAnkarafantsika National Park在马达加斯加的西北部，我们的国际团队在其行为，栖息地，沟通和社会性方面已知很多。例如，我们知道金棕色的老鼠狐猴sleeps in groups，而在我们的研究中，发现灰小鼠狐猴主要是单独休息。考虑到小鼠狐猴被指定为“马拉松卧铺”，他们可以轻松地花17个小时的睡眠，这种社会差异很可能是影响骨质侵扰的影响因素之一。

到目前为止，缺乏对近端侵扰的系统调查和对潜在影响因素的评估。我们首先发现，两种小鼠狐猴物种的个体均托有吮吸虱子，tick虫和两种螨虫。

The two mite species collected in our study could not yet be identified to the species level, as there are no reports of comparable mites infesting mouse lemurs. More surprising was the fact, that collected lice and tick specimens, even though they were morphologically similar to previously described species, showed distinct differences when comparing them based on genetic information. These findings highlight the value of additional genetic analyses, especially when trying to identify possible pathways for disease transmission. Are we actually dealing with the same ectoparasite species on two different host species, or is there a natural barrier which the parasite cannot cross?

此外，我们的发现表明，主机睡眠场所的社会程度以及睡眠组成员之间的相关社会修饰会影响鼻虫侵扰的风险。我们还发现，在计划，进行或比较研究时，在非载岩发生的季节性变化中需要牢记。

今年春天，Sifakas的大死亡(a larger lemur species) was observed in a private reserve in the south of Madagascar, possibly due to a parasite or tick-borne disease. In one part of the Ankarafantsika National Park, close to our study site, our team furthermore observed a potentially alarming population decline in the Golden-Brown Mouse Lemur. This emphasizes the importance of a comprehensive investigation of the current host-parasite interactions, to identify potential threats and pathways for pathogen transmission.