A bit on Jacks/Carangidae and Hyperostosis

I don't have too terribly much to say, other than to share some Carangidae tilly bone pictures and information I found in a fossil book and give a little appreciation to the family of the tilly bones I found!
First, some interesting facts from "Swollen bones in jacks and relatives (Teleostei: Acanthomorphata: Carangidae)" by Bruno Chanet (

  1. Tilly bones are more frequent in Cutlassfish/Trichiuridae, Drums/Sciaenidae and Jacks/Carangidae, species, but are most frequent in Jacks
  2. The bone overgrowth in jacks appears "with increasing specimen size", and so is found in larger and older fish.
  3. ...more ↓
Posted on June 07, 2022 05:49 AM by lizardking lizardking | 0 comments | Leave a comment
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"Tilly bones" are bones that exhibit excessive bone growth, or hyperostosis. They are named after paleontologist Dr. Johanna Gabrielle Ottelie Edinger, or simply 'Tilly'.
These over-grown bones are only found (to our current knowledge) in marine fish, though it is not known why.

Despite being a common and widely known phenomenon, they are not well understood. And they are ...more ↓

lizardking created this project on July 15, 2019
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