Phylogeny of the House Dust Mites and Relatives: Evolution or Devolution of Parasitism?

该项目将使用现代系统方法来解释屋尘螨及其近亲的起源和进化。这些尘螨属于热释粉科，是数百万人对房屋灰尘过敏的主要原因。寄生在鸟类和哺乳动物身上的拟革螨属于一个更大的类群--拟革螨，其中几乎只包括寄生虫。大多数工作人员认为焦草科是许多寄生虫谱系的祖先群体，原因很简单，因为这个科包括唯一的非寄生拟鳞翅目物种，即住在鸟巢或哺乳动物巢中的屋尘螨及其亲属。另一种假说表明，屋尘螨是从永久寄生的祖先进化而来的，这违反了进化的老生常谈--曾经是寄生虫，永远是寄生虫。这项研究的主要目标是确定寄生螨类是否形成一个单一的进化谱系。来自至少140个物种的12个不同线粒体和核基因的核苷酸序列数据将使用最新技术进行分析，这些基因代表了补骨脂及其近亲的大部分高级多样性。此外，在这项研究中，已经并将发现一些新物种。这个项目还将为本科生、研究生和博士后提供系统学、分子系统发生学和寄生虫学方面的培训。在过去的两个资助周期中，20多名本科生以及6名博士后和博士后在国际学生联合会的实验室接受了培训，其中一半以上是妇女，一些人属于代表性不足的少数民族。该项目还向年轻一代的鸟类学家提供了接触，并接触到了这些寄生虫生物学方面的合作项目。

This project will use modern systematic methods to explain the origin and evolution of the house dust mites and their relatives. These mites, in the family Pyroglyphidae, are the primary cause of house dust allergy in millions of people. Pyroglyphid mites belong to a larger group of mites, the Psoroptidia, which includes almost exclusively parasites, living permanently on the bodies of birds and mammals. Most workers regard the Pyroglyphidae as the ancestral group for many parasite lineages, simply because this family includes the only non-parasitic psoroptidian species, i.e. the house dust mites and their relatives living in bird or mammal nests. Another hypothesis suggests the house dust mites have evolved from permanently parasitic ancestors, violating the evolutionary truism once a parasite, always a parasite. The primary objective of the study is to determine whether the parasitic mites form a single evolutionary lineage. Nucleotide sequence data from 12 different mitochondrial and nuclear genes obtained from at least 140 species representing most of the higher level diversity of psoroptidians and their relatives will be analyzed using the latest techniques. Furthermore, a number of new species have been and will be discovered during this study. These will be described and a new classification of the Pyroglyphidae proposed.This project will also provide training in systematics, molecular phylogenetics and parasitology to undergraduate, graduate and post-doctoral students. Over 20 undergraduate students and six doctoral and postdoctoral students have been trained in the PI's lab over the course of the last two funding cycles, over half of them women and several belonging to underrepresented minorities. This project also provides outreach to a younger generation of ornithologists and exposure to these collaborative ventures in parasite biology.