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Are Dolphins Mammals

Answer To The Question: Are Dolphins Mammals?

Are dolphins mammals?  If you are wondering about the answer to this question, you can join a group of millions of individuals in the world who are asking the same thing.  Of course, most people automatically assume that they are a fish because after all, they do live in the water, however, there are a few details that set these captivating creatures apart from the rest of the ocean-dwellers.  So, really the question that you should be asking is “Why are dolphins mammals?”

Although dolphins live in the water, they are no more a fish than a human, horse or monkey.  Mammals are named after the Latin word that means “breasts” since breast milk is produced by female mammals to nurse their young.  Additionally, mammal babies are always born live.

Mammals have backbones, sweat glands and hair.  They are warm-blooded and come equipped with a heart that typically has four chambers that circulates blood through the body that carries oxygen that is breathed in.  Also, all mammals have less than four limbs with two mandatory front limbs.


If you are still wondering “Why are dolphins mammals?” it is easiest to understand the answer if you break down the features of one.  Dolphins have two flippers that are considered their two front limbs that are required to be a mammal.  They do not have any additional limbs however, they are equipped with flukes at the dorsal and tail fin.  These flukes act like paddles to keep the dolphin balanced while he is swimming.

Although most dolphins have no actual hair, they do have hair follicles.  These are believed to perform some type of sensory function.  Another feature that dolphins have that make them mammals is that they are warm-blooded.  They have lungs and they do need to come to the surface to breathe air in through their blowhole.  Interestingly, new born calves have to surface and breathe much more frequently than adults.

See Related: Dolphins Habitat


The last trait that dolphins must possess to be considered mammals is nursing behaviors.  A baby dolphin takes nearly one year to develop inside his mother’s womb, some species take even longer.  Labor typically lasts roughly 35 minutes and the mother has to immediately get her calf up to the surface of the water so that he can breathe.  Like every other mammal, the calf nurses right at the nipple however, he does not have to suck, the milk simply streams right into his mouth.  Every couple of seconds, the young dolphin has to take a break from nursing to rise to the surface to breathe.


Now that you know the answer to your, “Are dolphins mammals?” question, it is interesting to take a look at why these beautiful creatures are so loved and so mesmerizing.  Dolphins are considered one of the most intelligent animals on the planet.  They are social and have even been known to form super-pods of over 1,000 dolphins.  They form extremely strong bonds and will stay with ill or injured individuals, bringing them to the surface to breathe when needed.  Dolphins have even been known to protect swimmers from shark attacks by swimming around them.

Dolphins have a very big vocabulary, creating a large assortment of sounds and some even have a signature whistle that they use to identify themselves.  One of the greatest qualities about dolphins is how playful they are.  They play-fight with each other, tangle themselves up in seaweed and harass other creatures such as turtles and seabirds.  They are also found interacting with swimmers and jumping the waves left behind by boats.

Unfortunately, the biggest threat to dolphins are humans and some species such as the Yangtze River dolphin are now extinct.  You can do your part to save these magnificent mammals by only buying fish products that have a dolphin-safe label and never littering plastic or any other garbage into the ocean.

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