@misc{Ponton_Fleur_(1980–_)_Variation_2004,
 author={Ponton, Fleur (1980– ) and Elżanowski Andrzej and Castanet Jacques and Chinsamy Anusuya and Emmaanuel de Margerie and Armand de Ricqlès and Cubo Jorge and Polska Akademia Nauk. Muzeum i Instytut Zoologii.},
 editor={Museum and Institute of Zoology, Polish Academy of Sciences},
 copyright={Rights Reserved - Free Access},
 address={Warszawa},
 howpublished={online},
 year={2004},
 language={eng},
 abstract={The core of the limb bone cortex of mammals and birds is made of rapidly deposited, fibro-lamellar bone tissue (also present in non-avian theropods), which is usually surrounded by an avascular outer circumferential layer (OCL) of slowly deposited parallel-fibered bone. We present the first comparative allometric study of the relative OCL thickness (expressed as a fraction of the diaphyseal radius) in modern birds. Body size explains 79% of the OCL variation in thickness, which is inversely correlated with size, that is, shows negative allometry (slope -0.799). This may explain the apparent absence of OCL in the ratites. Since the OCL is deposited at the end of growth, we propose that its relative thickness probably correlates with the amount of slow, residual growth, which our results suggest to be on the average larger in small birds.},
 type={Text},
 title={Variation of the outer circumferential layer in the limb bones of birds},
 volume={39},
 number={2},
 journal={Acta Ornithologica},
 publisher={Museum & Institute of Zoology},
 keywords={bone histology, postnatal growth, ossification, skeleton, periosteal bone, phylogenetically independent contrasts},
}