There are several animals as smart as humans. One such smart creature is a dolphin. These creatures are commonly related to whales. The Killer Whale, also called an Orca, is the largest, longest, and heaviest species of dolphin in the world. There are 36 species of dolphins identified on the earth. Depending on the species, dolphins range in color from white to pearl and pink to darker shades of brown, gray, blue and black.
Dolphins have smooth skin, a pair of flippers, and a dorsal fin. They also have a long slender snout with about 100 teeth. Dolphin teeth are conical, meaning cone-shaped, and sharp. That means that they are used for grasping, not chewing. They have a set number of teeth for a lifetime, which means they won't grow a new tooth when one falls out. They also have a single blowhole on the top of their head, which has a flap for it to open and close.
Have you ever wondered how dolphins sleep in the ocean and get air at the same time? Surprisingly, if they fall asleep in the ocean, they'd drown and won't be able to breathe! Because of their body structure and bone type, they have the ability to hold more oxygen than humans. Thus, they are more buoyant than humans. Rather than drowning, they float about 10 inches (25 centimeters). Small movements in their flukes, or tails, periodically push them up so they can open their flap to take a breath. They sleep with one eye open and only half of their brain shuts down, probably to watch out for predators!
Dolphins have an eye on each side of their head. Each eye moves separately; so, they can see ahead, to the side, and behind them. They can see well underwater and above water. Their vision can be compared to a dog's or cat's vision. Dolphins that live in rivers often have a less developed vision, probably because they live in murky water where good eyesight won’t be useful.
Dolphins communicate with a series of whistles, clicks, and other sounds. They also have a signature whistle click, called a ¨name. ¨ They make these sounds by releasing air through the blowhole at the top of their head. They control the blowhole, making it larger or smaller. Bottlenose dolphin researchers also think slow clicks and high-pitched whistles are signals of happiness, while low squawks represent annoyance.
Dolphins also have a method of hunting called echolocation. Echolocation works when a dolphin makes sounds that travel underwater, bounce off something, and return as an echo. Echolocation makes it easier for a dolphin to find food and avoid predators. Dolphins that live in rivers have excellent echolocation to find food in dark or murky waters.
Dolphins also have ears in the form of holes. Dolphin’s ear holes are about the size of a crayon point, but it has the best hearing in all the animal kingdom. They receive sound through their jawbone and head, and the sounds pass through tiny bones of their inner ear.
Dolphins’ natural abilities are fast swimming and leaping clear out of the water, which makes them such entertaining performers. In fact, bottlenose dolphins, white-sided dolphins, and spinner dolphins are often used in TV shows, movies, and marine mammal demonstrations for this reason. Dolphins are also known to travel with ships leaping in front of the bow and swimming there.
Dolphins live in rivers and oceans. Some are found on coastlines, but others live far out in the sea. Some dolphins also use their method of “talking” to herd fish into what’s called a bait ball, which is a tight ball of a school of fish. Dolphins usually eat fish, octopus, squid, & shrimp. Killer whales feed on seals, smaller whales, penguins, birds, and even small walrus. Dolphins don’t drink sea water, they get water from the fish they eat.
Dolphins live in pods that exist in five to hundreds of animals. Some can also swim and roll in formation just like synchronized swimmers. Dolphins are social creatures too. They help one another in many cases, like if one is hurt or if a female is giving birth. They push the female to the surface so it can breathe. Dolphins are so powerful that they could kill a large shark by ramming it only with its snout.
Dolphins have very few predators because they are smart. Their predators are sharks, killer whales, and humans. Sharks are very aggressive and will take any chance to kill a hurt, sick or baby dolphin. Orcas are called the “wolves of the sea” and will take any chance to prey on a lonely dolphin. Humans can be the biggest threat because many people eat dolphins for their meat. Many people who eat dolphins say that their meat tastes just like many other types of meat, is much healthier, and can be substituted for beef, pork, or chicken.
Dolphins are not only fascinating creatures to watch, but they are very interesting to learn about!