Project 2121: K. Padian, S. Werning, J. R. Horner. 2015. A hypothesis of differential secondary bone formation in dinosaurs. Comptes Rendus Palevol.
Specimen: † Hypacrosaurus stebingeri (MOR:549)


We propose the hypothesis that in the long bones of large, rapidly growing animals, secondary osteons may form to a greater degree in smaller bones than in larger ones for reasons that may have more to do with the interplay between element-specific growth rates and whole-body metabolic rates than with mechanical or environmental factors. We predict that in many large animals with rapid growth trajectories and some disparity in size in the long bones and other skeletal elements, the largest bones will show less secondary remodeling than smaller ones. The reason is that, whereas the largest bones are increasing their dimensions too rapidly to accommodate much secondary reworking (until they approach full size), the smaller bones that are not increasing in size as rapidly must still process the flow of metabolites through their elements, and this is manifested in secondary remodeling. This hypothesis does not contradict or undermine other explanations, but rather adds an additional one that focuses more on growth and metabolic rates with respect to bones of different size in the same skeleton. Because the timing of onset of remodeling and the pace of its progression both vary by element, caution must be taken when using secondary remodeling to infer the overall ontogenetic stage of the animal.

Read the article »

Article DOI: doi:10.1016/j.crpv.2015.03.002

Project DOI: 10.7934/P2121,
This project contains
  • 14 Media
  • 1 Taxon
  • 1 Specimen
Total size of project's media files: 41.07M

Download Project SDD File
Currently Viewing:
MorphoBank Project 2121

    This research
    supported by

    Authors' Institutions

    • University of California Berkeley

    • Museum of the Rockies

    • Stony Brook University


    member name taxa specimens media media
    Sarah Werning
    Project Administrator
    Jack Horner
    Full membership
    Kevin Padian
    Full membership

    Project has no matrices defined.

    Project views

    type number of views Individual items viewed (where applicable)
    Total project views18624
    Project overview3020
    Media views11293Media search (3919 views); M374261 (510 views); M374271 (542 views); M374274 (512 views); M374267 (542 views); M374263 (571 views); M374268 (532 views); M374264 (547 views); M374272 (536 views); M374262 (537 views); M374266 (532 views); M374269 (521 views); M374273 (496 views); M374265 (505 views); M374270 (491 views);
    Specimen list1900
    Taxon list1659

    Project downloads

    type number of downloads Individual items downloaded (where applicable)
    Total downloads from project298
    Media downloads1M374267 (1 download);
    Project downloads297