MadSci Network: Zoology |
Breastfeeding, mammary glands, and nipples are only characteristic of mammals. Therefore, to the best of my knowledge, no dinosaur or other reptile could ever breastfeed their young. I suspect that the artist of the book to which you refer was either terribly misinformed or was depicting some kind of bony spines found in some dinosaurs and reptiles. admin note: For a good source on the evolution of dinosaurs (and nipples) have a look at this article: http://www.askwhy.co.uk/awwls/01/030justbiglizards.html
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