Cartilaginous Fishes • Cartilaginous fishes (Chondrichthyes) have a skeleton made not of bone, but of cartilage, which is lighter and more flexible than bone • Cartilaginous fishes have well- developed jaws and paired fins for efficient swimming • Most cartilaginous fish also have rough, sandpaper-like skin, the result of placoid scales pointed tip directed backwards
Cartilaginous Fishes. Cartilaginous fishes ( Chondrichthyes) have a skeleton made not of bone, but of cartilage , which is lighter and more flexible than bone Cartilaginous fishes have well-developed jaws and paired fins for efficient swimming - PowerPoint PPT Presentation
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Cartilaginous Fishes
• Cartilaginous fishes (Chondrichthyes) have a skeleton made not of bone, but of cartilage, which is lighter and more flexible than bone
• Cartilaginous fishes have well-developed jaws and paired fins for efficient swimming
• Most cartilaginous fish also have rough, sandpaper-like skin, the result of placoid scales
pointed tip directed backwards
Cartilaginous Fishes
• Cartilaginous fishes include sharks, skates, rays and chimeras, or ratfishes
• Nearly all are marine• ~350 species of sharks; ~500 species of skates
and rays; 30 species of chimeras
Sharks (cue scary, cello music)
• Sharks are often referred to as living fossils because many of the species alive today are similar to ones that swam the seas >100 million years ago
• Sharks have powerful jaws with rows of numerous sharp, often triangular teeth– Lost or broken teeth are quickly replaced by
another, which shifts forward from the row behind it as if on a conveyor belt