Compound eyes in the Chengjiang biota
2012
Schoenemann, B., Universität Bonn (Germany). Steinmann-Inst. für Geologie, Mineralogie und Paläontologie | Clarkson, E.N.K., University of Edinburgh (United Kingdom). Grant Inst. School of Geosciences
The oldest metazoan record is that from the Chengjiang Biota, of the lower Cambrian of China (~525 to 520 Ma). This fauna is dominated by arthropods, even here the structures of compound eyes can be well observed and analysed. By modern physiological methods it is possible to assign the ancient owners of these compound eyes to their light ecological habitats. The structures of the found compound eyes are different – there are the more basal, grapelike arranged facets in stem-line close arthropods, but also advanced systems, comparable to modern compound eyes with densely packed hexagonal facets are represented. Because compound eye designs adapt to the light ecological demands these designs are highly variable and hardly of use for systematic analyses. A second visual system besides the compound eyes, median eyes, has been discovered in some of the arthropods. These are autapomorphic for euarthropods, and may be of great use for cladistic analyses.
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