All speculation concerning the species are educated guesses, yes. However, a Medical Doctor should be making no such guesses unless they understand the dentician of several suspect species. They furthermore need to understand the predation habits of those species. I somewhat qualified myself by telling you about the fact I dive with them. You can see my dive videos of me diving with sand tiger sharks at youtube/fpsndiver.
I also denied my anonymity somewhat with my 'screenname'. It shouldn't be hard to track me down. Chondrichtyan fishes are my speciality. So, no, I'm not trying to feel or be superior to anyone, however, nothing qualified that doctor (that was disclosed) to make his guess. His guess could demonize a threatened species of sharks which just happen to have local aggregate breeding grounds about 15 miles offshore from here.
I didn't guess the specific species, I gave a broad range. Again, I say this was probably a requiem shark, a family which includes many species with triangular teeth designed to cut and separate flesh. Sand Tiger's teeth are not designed to do so. Basing that presumption (which is what it is) on the evidence (photographs of the injuries) when one understands chondrichtyan dentition is a little better than throwing a specific breed of shark under the bus without any supporting expertise. That is all.
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