@julie-niederkorn, teeth can be a little more challenging than bone. Teeth do become denser as they incorporate more sediment, but the density difference between a modern and fossil tooth isn’t as a great as it is between modern and fossil bone. The tap test doesn’t work because enamel will make that ceramic sound regardless of it being modern or fossil. The burn test can be done by burning parts of the root rather than the enamel itself, but it doesn’t work quite as well as it does for bone. The coloration doesn’t help much for teeth either because the rate of color change is highly variable and depends more on the environment than the fossil itself. For example, if a tooth sits in the sun for a long time, it can be bleached white despite being a fossil. Long story short, it can be a lot more challenging to distinguish a fossil tooth from a modern tooth. I’ve been collecting in the Gainesville creeks which have fossils from 40 million years ago to animals that just died yesterday, so I’ve been struggling with distinguishing modern versus fossil teeth as well.
As for the domestic question, I’m not quite sure. I’m pretty sure, Sus scrofa is commonly called the wild boar and Sus scrofa domesticus is a sub-species for the modern domesticated pig (some call it a separate species Sus domesticus). It’s very hard to say if your tooth is a fossil, but it certainly seems old from the picture. Admittedly, I don’t know much about the fossil record of pigs, but perhaps some others know more. @bmacfadden @smoran @jnance any thoughts on this?