Simple Toadfish Grunts May Contain Complex Information
Transparent specimen of three-spined toadfish. The simple-sounding grunts and hoots of the toadfish contain surprisingly complex information. Sounds hidden within the toadfish calls may communicate everything from, “It’s me again, can we spawn?” to, “It’s your neighbor, but get away from my nest.”
Iceland spar is a clear, transparent, colorless crystallized variety of calcite (calcium carbonate, CaCO3). Large pieces are split along natural cleavage planes to form natural rhombs. Iceland spar is probably best known for exhibiting the optical property of double refraction - so, anything viewed through the crystal appears double.