Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology

  title={Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology},
  author={Lars Schmitz and Ryosuke Motani},
  pages={705 - 708}
Comparison of eye structures between fossils and modern species suggests that Mesozoic archosaurs were active day and night. Variation in daily activity patterns facilitates temporal partitioning of habitat and resources among species. Knowledge of temporal niche partitioning in paleobiological systems has been limited by the difficulty of obtaining reliable information about activity patterns from fossils. On the basis of an analysis of scleral ring and orbit morphology in 33 archosaurs… 
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Comment on “Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology”
It is not yet possible to reconstruct the activity patterns of most fossil archosaurs with a high degree of confidence because of serious flaws in the data, methods, and interpretations of this study.
Response to Comment on “Nocturnality in Dinosaurs Inferred from Scleral Ring and Orbit Morphology”
This work demonstrates that it is not yet possible to infer the diel activity patterns of fossil archosaurs with high confidence through unscreened data, untenable assumptions, and inappropriate methods, and follows ecomorphological and phylogenetic principles in a probabilistic framework, resulting in statistically well-supported reconstructions.
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