Giants and dwarves: Reconstructing the evolution of size and life histories within Myriapoda

巨人和矮人：重建多足纲的体型和生命史的进化

• 批准号: 516824140
• 负责人: Professor Dr. Joachim Tobias Haug
• 金额: --
• 依托单位: Zoologische Staatssammlung München
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/516824140?language=en
• 关键词: Giants; dwarves; Reconstructing; evolution; size

Representatives of the group Myriapoda, i.e. centipedes, millipedes, and their relatives, are generally known as rather small animals living in the soil and leaf litter. Even though the group Myriapoda comprises far less species than, for example, the group Insecta, centipedes and millipedes are important components of the modern fauna. They fulfil important ecological roles, for example, as decomposers or impressive predators to name just two examples. While the majority of modern representatives of Myriapoda has a body size within the millimetre range, much larger ones live in the tropics, with a maximum length of slightly more than 30 centimetres. Hence, it is even more astonishing that during the late Palaeozoic, especially in the Carboniferous (ca. 359–299 million years ago), fossil representatives of this group reached body sizes of up to two metres. Of special interest in the context of body size in Myriapoda is the comparison of the largest representatives, the exclusively fossil representatives of Arthropleuridea, and the smallest representatives, bristly millipedes (Polyxenida). The latter occur both in the modern fauna and as fossils preserved in ambers of different ages (from 130 to 15 million years ago). Despite their significant size difference, both groups have been suggested to be sister groups, hence apparently strong evolutionary changes in body size occurred. We explore two aspects: the support for a sistergroup relationship between Arthropleuridea and Polyxenida, and the size changes of bristly millipedes through time. A challenge in the comparison of size in fossils is that small representatives could simply be immatures. Therefore, we will include those stages into our comparisons which do not yet have the full segment number. Such immature stages can be recognised for modern and also for fossil representatives of certain lineages (e.g. Lithobiomorpha or Polyxenidae) and with this be identified to distinct stages. When these stages are compared, the ontogenetic variation, i.e. the variation during individual development, can be corrected. The investigations and analyses of these finds from 130 million years ago to today will provide for a better understanding of the changes in ecological functions through time.

多足类的代表，即蜈蚣、千足类及其近亲，通常被认为是生活在土壤和树叶枯枝落叶中的相当小的动物。尽管多足动物群的物种远远少于昆虫纲，但蜈蚣和千足虫是现代动物群的重要组成部分。它们扮演着重要的生态角色，例如，分解者或令人印象深刻的捕食者，仅举两个例子。虽然现代多足类的大多数体型都在毫米范围内，但生活在热带地区的体型要大得多，最大长度略高于30厘米。因此，更令人惊讶的是，在晚古生代，特别是在石炭纪(约3.59-2.99亿年前)，这一组化石的代表达到了两米大小的身体。在多足纲的身体大小方面，特别感兴趣的是对最大的代表，节肢动物总科唯一的化石代表，和最小的代表，刚毛千足类(多齿纲)的比较。后者既出现在现代动物群中，也作为化石保存在不同年龄的琥珀中(从1.3亿到1500万年前)。尽管它们的体型差异很大，但这两个群体被认为是姐妹群，因此显然在体型方面发生了强烈的进化变化。我们从两个方面进行了探讨：节肢动物总科和多足类之间姐妹群关系的支持，以及千足类动物的大小随时间的变化。比较化石的大小面临的一个挑战是，小的代表可能只是不成熟的。因此，我们将把那些还没有完整段号的阶段包括在我们的比较中。这样的未成熟阶段可以被识别为现代的，也可以被识别为某些谱系的化石代表(例如石双形目或多孔虫科)，并由此被识别为不同的阶段。当对这些阶段进行比较时，个体发育变异，即个体发育过程中的变异，可以得到纠正。从1.3亿年前到今天，对这些发现的调查和分析将有助于更好地了解生态功能随时间的变化。