How to See the Differences Between a Dolphin and a Shark
- 1). Observe the shape of the dorsal fin. A dolphin's dorsal fin has a curved tip, while a shark's is triangular-shaped.
- 2). Count the dorsal fins. Dolphins have one dorsal fin on their back. Sharks have a secondary smaller dorsal fin closer to the tail.
- 3). Look at the tail orientation and tail movement while the animal is in motion. Dolphins have horizontally positioned tails, while the sharks' tails are vertically oriented. Dolphins glide in the water by moving their horizontal tails up and down. Sharks propel themselves by moving their vertical tails from side to side.
- 4). Check the area near the head. If you observe slash-like gills the animal is a shark and uses the gills to breathe. Dolphins will not have gills, as they are mammals and breathe through their lungs.
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