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Oceanic dolphin

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Dolphins live in the sea.

Dolphind.jpg
Dolphind.jpg
They swim very fast. They use sounds to find things. They eat fish and squid. Mothers care for their babies.
PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg
Do you like dolphins?

31 words

Dolphins live in the big, blue sea.

Dolphind.jpg
Dolphind.jpg
They have strong bodies that look like torpedoes. This shape helps them swim very fast. They use a thick layer of fat to stay warm.
PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg
This fat is under their skin. Most dolphins eat fish and squid. They use sounds to find their food. They make clicks and whistles to talk.
Delfinekko.gif
Delfinekko.gif
Mothers stay with their babies to keep them safe. Dolphins are very smart sea animals.

76 words

Oceanic dolphins live in the sea. There are about forty different kinds.

Dolphind.jpg
Dolphind.jpg
Some dolphins look like whales. These are called blackfish. The orca is the largest dolphin.
PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg

Dolphins have strong, muscular bodies. Their shape is like a torpedo. This helps them swim fast. They use a tail fin to move. They use flippers to steer. Some can swim at 29 km/h.

Delfinekko.gif
Delfinekko.gif

Dolphins stay warm with blubber. Blubber is a thick layer of fat under the skin. It also helps protect them.

Dolphins use sound to see. They use a part of their head called a melon. The melon is made of fat. It helps them send out clicks. This is called echolocation. It helps them find food and see shapes.

Dolphins live in large groups called pods. Some pods have a thousand dolphins! Mothers raise their calves alone. A calf is a baby dolphin. The mother feeds the baby for a long time.

Sea World1.jpg
Sea World1.jpg
Most dolphins eat fish or squid. Some eat birds or other sea animals.

171 words

Oceanic dolphins are amazing animals that live in the sea. There are about forty different species in this family.

Dolphind.jpg
Dolphind.jpg
Some dolphins are so big that people call them whales. These are called blackfish and include the orca. The orca is the largest known dolphin.
PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg
Dolphins are very different from porpoises or beluga whales. They belong to a group called Delphinidae. Most species like warm waters near the equator. However, some like the right whale dolphin prefer cold water.
Akrotiri dolphins.jpg
Akrotiri dolphins.jpg

These animals have bodies shaped like torpedoes to help them swim. Their bodies are muscular and very streamlined. They use a large tail fin to move through the water. They also use flippers to steer their way.

Delfinekko.gif
Delfinekko.gif
Some dolphins can swim at 29 km/h for short distances. The orca can even reach speeds of 40 km/h. Their necks are stiff to help them stay stable while swimming. This means they cannot turn their heads easily. They also have a layer of fat called blubber. This blubber keeps them warm in cold water.
Etruridelphis-giuliiBologna.JPG
Etruridelphis-giuliiBologna.JPG

Dolphins use sound to find things in the ocean. This special way of seeing is called echolocation. They have a fatty part on their head called a melon. The melon helps them send out high-frequency clicks. These clicks bounce off objects to show the dolphin's size and shape.

Delfinekko.gif
Delfinekko.gif
They also use low whistles to talk to each other. Their ears are special for hearing underwater. Instead of an outer ear, they receive sound through their throat. This helps them hear direction very well. It is a very clever way to live in the deep sea.

Many dolphins live together in large groups called pods. Some pods can have as many as one thousand dolphins!

Sea World1.jpg
Sea World1.jpg
Some pods have a loose social structure. This means members join or leave often. Other pods are more permanent groups. Most dolphins eat fish or squid. The orca is a special hunter that also eats birds and seals. They are all purely carnivorous, which means they only eat meat. They can have between 100 and 200 teeth.

Dolphins are famous all over the world. People have painted them in ancient art. They also appear in movies like Free Willy.

Sea World1.jpg
Sea World1.jpg
Sometimes dolphins are kept in captivity for shows. The bottlenose dolphin is the most common one in shows. In 2012, fewer than 50 orcas lived in oceanariums. Dolphins also face hard jobs in the wild. They deal with marine pollution and habitat loss. Some are even caught by accident in fishing gear. We must learn how to protect these wonderful sea animals.

436 words

Oceanic dolphins, known scientifically as Delphinidae, are a diverse family of marine mammals. They live in oceans all over the world. There are close to forty different species recognized today.

Dolphind.jpg
Dolphind.jpg
This family is part of a larger group called Delphinoidea. This group also includes porpoises and the Monodontidae, which are beluga whales and narwhals. Some dolphins are so large that people often call them whales. These are sometimes called "blackfish." This group includes the orca, the pilot whale, and the false killer whale. Even though they have "whale" in their names, they are still part of the Delphinidae family.

PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg
The bodies of these animals are built for speed in the water. They have a streamlined, torpedo-shaped body that is very muscular. Their limbs are modified into flippers, which contain four digits. They also have a large tail fin to push them through the water. To help them swim straight, they have a dorsal fin on their backs. This prevents them from spinning involuntarily. Their neck vertebrae are fused together. This makes their necks inflexible, which helps them stay stable at high speeds. However, it also means they cannot turn their heads easily. Some species can swim at 29 km/h for short distances. The orca is even faster, reaching speeds of up to 40 km/h.

Delfinekko.gif
Delfinekko.gif
Dolphins use a sophisticated system called echolocation to navigate. They produce high-frequency broadband clicks between 80 and 220 kHz. They send these sounds out using a fatty organ in their forehead called a melon. These clicks bounce off objects and return to the dolphin. This process, known as biosonar, helps them understand the shape and size of objects.
Etruridelphis-giuliiBologna.JPG
Etruridelphis-giuliiBologna.JPG
Dolphins also communicate using low-frequency whistles. Their hearing is specially adapted for the ocean. Instead of an outer ear, they receive sound through their throat. The sound then passes through a fat-filled cavity to the inner ear. Air-filled sinus pockets isolate the ear from the skull. This allows them to have excellent directional hearing underwater.

Akrotiri dolphins.jpg
Akrotiri dolphins.jpg
Dolphins live in social groups called pods. These pods can be very large, sometimes containing one thousand individuals. Each pod may forage over areas spanning hundreds of square kilometers. Some pods have a loose social structure where members join or leave often. Other pods are more permanent. Some of these groups might be dominated by a single male and a harem of females. All oceanic dolphins are purely carnivorous. Most species eat fish and squid, or small crustaceans. However, some species are specialized. The orca is a notable example because it also eats marine mammals and birds.

Sea World1.jpg
Sea World1.jpg
The life cycle of a dolphin is quite specific. Gestation, or the time the baby grows inside the mother, lasts between 10 and 18 months. Each birth results in a single calf. Calves are typically born during the spring or summer. In many species, the mother bears all the responsibility for raising the young. Some mothers will fast, or go without eating, to nurse their young for long periods. To survive in cold water, dolphins have a thick layer of fat called blubber. This blubber provides insulation. It also acts as a layer of protection against predators. Calves are born with only a thin layer of blubber.

Delfinekko.gif
Delfinekko.gif
Scientists use many tools to study these animals. Recent molecular analyses, which look at DNA, show that some dolphin groups are not organized the way we once thought. This means the way we classify them, known as taxonomy, is likely to change. For example, in 2025, there was a significant revision of the genus Lagenorhynchus. Dolphins are also known for their ability to hybridize. This means different species can sometimes breed to create a hybrid, such as a "wholphin."

Sea World1.jpg
Sea World1.jpg
Dolphins have a deep connection to human culture. They appear in ancient art, such as frescoes from 1600 BC. They are also famous in modern movies, like the film Free Willy. Today, some dolphins are kept in captivity for shows. The bottlenose dolphin is the most common species found in these settings. In 2012, fewer than 50 orcas were found in oceanariums. Despite their fame, dolphins face many threats. They deal with habitat loss, marine pollution, and bycatch from fishing. In some places, such as Japan, they are also subject to dolphin drive hunting.

715 words
🖼️ Images & Media (7)
File:Etruridelphis-giuliiBologna.JPG
Etruridelphis-giuliiBologna.JPG
File:Dolphind.jpg
Dolphind.jpg
File:Delfinekko.gif
Delfinekko.gif
File:PacificWhiteSidedDolphine.jpg
PacificWhiteSidedDolphine.jpg
File:Dolphin Sashimi.jpg
Dolphin Sashimi.jpg
File:Sea World1.jpg
Sea World1.jpg
File:Akrotiri dolphins.jpg
Akrotiri dolphins.jpg
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