BIROn - Birkbeck Institutional Research Online

    Large batoid fishes frequently consume stingrays despite skeletal damage

    Dean, M.N. and Bizzarro, J.J. and Clark, B. and Underwood, Charlie J. and Johanson, Z. (2017) Large batoid fishes frequently consume stingrays despite skeletal damage. Royal Society Open Science , ISSN 2054-5703.

    [img]
    Preview
    Text
    Rhynchobatus and spines.pdf - Published Version of Record
    Available under License Creative Commons Attribution.

    Download (1MB) | Preview

    Abstract

    The shapes of vertebrate teeth are often used as hallmarks of diet. Here, however, we demonstrate evidence of frequent piscivory by cartilaginous fishes with pebble-like teeth that are typically associated with durophagy, the eating of hard-shelled prey. High-resolution micro-computed tomography observation of a jaw specimen from one batoid species and visual investigation of those of two additional species reveal large numbers of embedded stingray spines, arguing that stingray predation of a scale rivalling that of the largest carnivorous sharks may not be uncommon for large, predatory batoids with rounded, non-cutting dentition. Our observations demonstrate that tooth morphology is not always a reliable indicator of diet and that stingray spines are not as potent a deterrent to predation as normally believed. In addition, we show that several spines in close contact with the jaw skeleton of a wedgefish (Rhynchobatus) have become encased in a disorganized mineralized tissue with a distinctive ultrastructure, the first natural and unequivocal evidence of a callus-building response in the tessellated cartilage unique to elasmobranch skeletons. Our findings reveal sampling and analysis biases in vertebrate ecology, especially with regard to the role of large, predatory species, while also illustrating that large body size may provide an escape from anatomical constraints on diet (e.g. gape size, specialist dentition). Our observations inform our concepts of skeletal biology and evolution in showing that tessellated cartilage—an ancient alternative to bone—is incapable of foreign tissue resorption or of restoring damaged skeletal tissue to its original state, and attest to the value of museum and skeletal specimens as records of important aspects of animal life history.

    Metadata

    Item Type: Article
    Keyword(s) / Subject(s): cartilage, elasmobranch, predation, stingray spine, skeletal callus, tesserae
    School: Birkbeck Schools and Departments > School of Science > Earth and Planetary Sciences > UCL/Birkbeck Centre for Planetary Sciences
    Research Centre: Earth and Planetary Sciences, Institute of
    Depositing User: Charles Underwood
    Date Deposited: 29 Sep 2017 08:32
    Last Modified: 26 Jul 2019 21:48
    URI: http://eprints.bbk.ac.uk/id/eprint/19843

    Statistics

    Downloads
    Activity Overview
    77Downloads
    65Hits

    Additional statistics are available via IRStats2.

    Archive Staff Only (login required)

    Edit/View Item Edit/View Item