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A 390 million-year-old hyper-compound eye in Devonian phacopid trilobites
B Schoenemann1, E N K Clarkson2, C Bartels3
1Department of Zoology, Neurobiology/Animal Physiology and Biology Education, University of Cologne, Cologne, Germany. B.Schoenemann@uni-koeln.de.
Scientific Reports
|October 1, 2021
Summary
Phacopid trilobites possessed unique "hyper-compound eyes," a sophisticated visual system unlike any other in the animal kingdom. These complex eyes, featuring multiple individual compound eyes beneath each large lens, offered a unique visual surface during the Palaeozoic era.
Area of Science:
- Paleontology
- Evolutionary Biology
- Ophthalmology
Background:
- Trilobites were dominant marine arthropods in the Palaeozoic era.
- Most trilobites had apposition compound eyes (holochroal eyes).
- Phacopina suborder trilobites evolved distinctive schizochroal eyes with large lenses and wide interspaces.
Purpose of the Study:
- To investigate the sophisticated structure of phacopid trilobite schizochroal eyes.
- To determine if these eyes represent a novel visual system.
- To discuss the development, phylogeny, and neuronal infrastructure of this unique eye type.
Main Methods:
- Comparative analysis of trilobite eye structures.
- Morphological examination of schizochroal eyes.
- Phylogenetic and developmental inference.
Main Results:
- Phacopid schizochroal eyes are revealed as "hyper-compound eyes."
- Each large lens conceals an individual compound eye.
- A single phacopid eye comprises tens to hundreds of smaller compound eye systems.
Conclusions:
- Phacopid trilobite eyes represent a unique "hyper-compound eye" system, unprecedented in the animal kingdom.
- This sophisticated visual apparatus likely conferred specific advantages during the Palaeozoic.
- Further research is needed on the neuronal infrastructure and evolutionary implications.
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