• Pectoral flippers: Used for steering.
  

• Dorsal fin: Used for balance.
  

• Tail Flukes: Used for propulsion. While human babies are typically born head-first, dolphin calves are born tail first. This is because the tail (or flukes) is curled up inside of mom while she is pregnant. When the calf's flukes start to emerge, it is able to become more stiff and stable so that when the dolphin is born and mom brings the baby to the surface for its first breath, it is able to swim on its own and keep up by pumping and gaining speed with its strong and stable tail flukes.
  

• Blowhole: Allow the dolphin to come to the surface, easily take in air, and continue swimming.
  

• Melon: This is a mass of tissue found on the forehead of dolphins, and other toothed whales that is used to focus and amplify their vocalizations. This bump on the animals' foreheads is sometimes referred to as a "sound lens" and is crucial in echolocation.
  

• Hair: Dolphins are mammals, so they do have hair. When baby dolphins are born, they have hairs to effectively nurse from mom. Over time, the hairs will fall out and the dolphins have no hair on their bodies to reduce drag, or resistance, when swimming.

• Mouth and Teeth: Dolphins have approximately 100 teeth, which are cone shaped and pointy, made for catching prey. They are used to capture fish and some invertebrates which are then swallowed whole. Almost all dolphin species are homodonts, meaning they only have one type of tooth, versus humans, who have four types of teeth. As dolphins age, their teeth grow in layers, like a tree, so veterinarians can tell the age of a dolphin based on their teeth as well as the health of the animal by looking at tooth wear.
  

• Size: Bottlenose dolphins weigh between 300 pounds and 1,400 pounds and reach 6 feet to 13 feet in length (7).
  

• Lifespan: Bottlenose dolphins typically live 40-60 years.
  

• Appearance: Coloration ranges from light gray to almost black on top near their dorsal fin and light gray to almost white on their belly. In the ocean, countershading camouflages an animal from predators or prey. When viewed from below, an animal's lighter belly would blend in with the lighter sky above. When viewed from above, its darker back would blend in with the ocean bottom underneath.

How to Spot the Difference: Dolphin & Porpoise

Both animals are "toothed whales" (odontocetes) and use echolocation to communicate and navigate. Additionally, both dolphins and porpoises are incredibly intelligent, but porpoises tend to be more shy around boats and humans.

• Head: Dolphins typically have a long, "beaked" snout, whereas porpoises have a rounded face with no "beak."
  

• Dorsal Fins: If you are unable to see the animal's head, note their dorsal fin shape. Dolphins tend to have a more curved dorsal fin whereas porpoises have a more triangular dorsal fin.
  

• Body Length: Dolphins are typically larger in length than porpoises. Porpoises only reach a maximum of 7 feet. Dolphins typically range from 7-12 feet in length. Fun fact! Orca whales and pilot whales are considered members of the dolphin family but are called "whales" because of their size. If a dolphin or porpoise reaches 30 feet or above, they are referred to as whales.
  

• Number of Species: There are 33 species of dolphins and only 7 species of porpoises!

• Teeth: Dolphins' teeth are more "cone-shaped", whereas porpoises have teeth that are "spade-shaped."
  

Optional Course Materials

• Vaquita & Dolphin Coloring Sheet

• Dolphin Paper Doll Worksheet