from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A thickening of the bones of the ribs and vertebrae
from The Century Dictionary and Cyclopedia
- n. Literally, a thickening of the bone: specifically applied to an increase in the amount of the bony network or reticulum that more or less completely fills the long bones of some animals, notably the elephant among mammals and Dinornis among birds.
Sorry, no etymologies found.
It is this latter trait, the authors suggest, that best explains an anatomical detail peculiar to H. erectus, and which sets it apart from others in the family tree -- pachyostosis.
The ribs are elongate and moderately curved, with no sign of pachyostosis or osteosclerosis.
The Struthiocephalinae were described by Boonstra (1969) as having a long and fairly strong snout, as well as having undergone moderate pachyostosis.
The Struthiocephalini are characterised as having a reasonably long snout, and having a skull that has undergone moderate pachyostosis (King 1988).
These groups were based predominantly on the length of the snout and the degree to which the skull had undergone pachyostosis.
Sauropterygia) exhibiting pachyostosis from the Middle Jurassic of England.
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