Oceanography – Shark and Perch Comparisons
The ocean is one of the most diverse habitats, with a great variety of animals at all different depths. Fish are just one of the many different types of animals that call the ocean “home”. Today, our campers explored two types of fish (dissected earlier in the week) – a bony fish (perch) and a cartilaginous fish (spiny dogfish shark). They analyzed the similarities and differences between the two fish side by side, and quite literally got an ‘in depth’ view of the structures and functions of both fishes. One interesting investigation had the campers compare the livers of each fish.
Ask your camper: What happened when you placed both fish’s livers in water? The shark liver (markedly larger) floated while the perch liver sank. Why did this happen? The shark liver is largely involved with helping the shark remain buoyant in the water (perch have a swim bladder to help with buoyancy while the shark doesn’t).