Steller's sea cow & human ichthyosis: treebark-like skin
https://phys.org/news/2022-02-genome-steller-sea-cow-decoded.html
Could megalodon have been their main predator until 3.6ma?
The camou mossy oak skin of sirenians was perhaps a result of predation by megalodon super sharks. Megalodon were up to 50' long, had huge teeth, related to great whites (which are slightly warm-blooded), lived until 3.6ma and didn't have sonar. Seems
possible.
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