|MadSci Network: Other|
Hi, Not knowing exactly where you live or what these fossils are, I can only be general in my answer. The state of NJ was under the sea not so long ago, in geologic time. It was closer to the tropics and this warm, shallow coastal sea was rich in plankton and small animals that fed on them. Sharks and squid came in to feed on these smaller organisms. It was a rich, tropical coral reef. Most of the reef is gone now and only remnants can be found. It stretched from Maine to Florida. These shark teeth are common as sharks shead their teeth like you shead skin cells. Teeth in sharks are modified epidermal cells like scales on a fish. As old ones wear out and fall off, new ones grow behind them.
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