Reply to “Points of view in understanding trilobite eyes”

In an article dealing with the fine structure of the compound eyes of two trilobite species we showed evidence for the existence of crystalline cones1. This finding was discussed in the context of the putative close relationship between Trilobita and Mandibulata. Schoenemann and Clarkson offered some critical comments on several aspects of our article2. Here, we rebut the points raised by these authors.


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Policy information about availability of data All manuscripts must include a data availability statement. This statement should provide the following information, where applicable: -Accession codes, unique identifiers, or web links for publicly available datasets -A list of figures that have associated raw data -A description of any restrictions on data availability Field-specific reporting Please select the one below that is the best fit for your research. If you are not sure, read the appropriate sections before making your selection. Eyes of fossil specimens (trilobites) were examined using SEM, micro-CT and synchroton CT. For comparison, the eyes of recent arthropods were analysed using histology, light microscopy, and SEM.
One individual of each trilobite and each Recent arthropod species.
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Specimens of Asaphus sp. were collected by Gustaf Lindström at the end of the 19th Century at Gotska sandön, Gotland, Sweden. The specimen of Archegonus warsteinens was collected by Dieter Korn at Kalvarienberg/Kallenhardt, Germany Specimens of Asaphus sp. are deposited in the Naturhistoriska Riksmuseet, Sektionen för Paleozoologi, Stockholm (Sweden). The specimen of Archegonus warsteinens are deposited in the Museum für Naturkunde, Berlin (Germany).
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