Did you know that until the 16th century, mariners and seamen referred to sharks as "sea dogs"? Sharks have actually been around for a long time--many scientists think a variation of the shark existed from over 420 million years ago! Sharks belong to a large group of fish that have a skeleton made of cartilage instead of bone. Because of this, the only fossilized remains of ancient sharks are their teeth.The teeth of sharks grow in constantly to replace older ones that wear out. It is estimated that sharks can lose up to 20,000 teeth in their lifetime. In fact, some ancient sharks had teeth that grew as long as 4 inches.
This necklace features one such authentic fossil, although considerably smaller than the prodigious fangs of ancient sharks. The fossil hangs from a metal coil attached to a fully adjustable cord that fits all sizes. Makes a great gift for the shark fan in your life, as well as an excellent stocking stuffer or party favor. Always a big hit with marine biology teachers.
This caffeine molecule mug makes an excellent gift!
Use this temperature-controlled soldering station for a variety of soldering applications!
Shake the Pet Tornado clockwise and watch the mini tornado funnel form before your eyes!
A combination of three of our great discovery toys, all in one package!
Check out this amazing renewable energy science kit featuring the wonders of hydroelectric power!
Great reference card for chemistry and physics students.