Journal
JOURNAL OF PALEONTOLOGY
Volume 87, Issue 5, Pages 818-825Publisher
CAMBRIDGE UNIV PRESS
DOI: 10.1666/12-152
Keywords
-
Categories
Funding
- National Science Foundation [EAR 0921771]
- Directorate For Geosciences
- Division Of Earth Sciences [0921771] Funding Source: National Science Foundation
Ask authors/readers for more resources
Strophomenid brachiopods have long been interpreted as snowshoe strategists, with their flattened concavoconvex valves providing resistance to foundering in very soft sediments. There has been a sharp difference of opinion in whether the shells were oriented with their convex or their concave surface in contact with the sediment. This study, along with independent evidence from sedimentology, ichnology, and morphology, indicates that the strophomenids lived with their shells concave down (convex up). Experiments indicate the force required to push shells into soft cohesive muds is much greater for the convex up than for the convex down orientation. Forces also increase with shell curvature. All measured forces greatly exceed estimates of the downward force exerted by the weight of the shell, indicating that foundering resistance may not have been the key functional requirement. Instead, a convex up orientation would have provided resistance to overturning in currents, in particular if the valves gaped widely. The snowshoe may not be the relevant paradigm for the shell morphology of these forms. An alternative is that they functioned more as a tip-resistant base, similar to those of garden umbrellas or stanchions.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available