Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Zoological detective stories: the case of the facetotectan crustacean life cycle. | Journal of Biology BioMed Central Minireview Zoological detective stones the case of the facetotectan crustacean life cycle Gerhard Scholtz Address Humboldt-Universitat zu Berlin Institut fur Biologie Vergleichende Zoologie Philippstrasse 13 10115 Berlin Germany. Email Published 26 June 2008 Journal of Biology 2008 7 16 doi jbiol77 The electronic version of this article is the complete one and can be found online at http content 7 5 16 2008 BioMed Central Ltd Abstract The reconstruction of complete animal life cycles is sometimes a considerable problem even though the knowledge of the full life cycle may have far-reaching evolutionary implications. A new study published in BMC Biology on artificially induced metamorphosis in an enigmatic crustacean group that was only known from larval stages sheds new light on the evolution of parasitism. In our course on evolutionary biology we ask the students to compare larvae pupae and imagines of the mealworm beetle Tenebrio molitor with the aim of finding direct evidence that these specimens represent not different species but the stages that every individual of this hexapod species has to pass through. The students cannot solve this problem. In spite of the most meticulous comparative morphological analysis there is no way to show that a larva and an adult beetle belong together. Even modern molecular markers reach their limits when only part of the life cycle is known and we have no clue where to look for the missing stages. Thus the only method to resolve this issue is the direct observation of the life cycle including metamorphosis and change of shape during ontogeny. The early stages of a complex life cycle can have a morphology and an ecology that are dramatically different from those of the adults. Accordingly the history of zoology in particular during the 19th century is full of dramatic detective stories . An example is the detection by August Muller in 1856 1 that
