35 Fascinating Facts About Dolphins
Dolphins are just about everyone’s favorite animal to see at the beach or the aquarium, but these complex, multilayered creatures are more than meets the eye. They are social, highly intelligent, agile and enjoy many similarities with humans.
Check out these 50 fascinating facts you may not have known about dolphins.
Dolphins swallow without chewing.
Dolphins do have teeth but don’t use them to chew. They swallow smaller fish whole and break apart larger fish by rubbing or shaking them against another object.
Adults eat about 5 percent of their body weight daily.
A dolphin can easily kill a shark with its snout.
You never think of a shark being afraid of anything, but dolphins scare these usually fearsome predators because they actually use their snouts as a battering ram to kill them.
The dolphin’s snout is made of thick, solid bone, and dolphins have been known to position themselves under the shark and ram their snout into its underbelly, causing severe internal injuries.
The hippo and the dolphin may be related.
Scientists believe that dolphins and hippos evolved from the same four-footed land animal that walked the Earth some 40 million years ago. According to post-doctoral fellow Jean-Renaud Boisserie and other scholars at University of California, Berkeley, the hippopotamus was long believed to be related to the pig, but molecular evidence from fossils show otherwise.
The hippo is most closely related to cetaceans, which includes dolphins, porpoises and whales.
Dolphins have stomachs with three chambers.
Like cows and deer, dolphins have compartmentalized stomachs. Because they don’t chew with their teeth, their food masticates in the first chamber, they digest the majority of it in the second chamber, and the remainder of it is broken down in the third chamber.
From there, it empties into their intestines.
Dolphins are highly intelligent.
The dolphin may be the world’s smartest animal next to humans, and it all boils down to the size of their brains. Bottlenose dolphins, for example, have bigger brains than we do, and their brain-to-body-weight ratio is larger than that of the great apes.
Their complex neocortex also allows them to exhibit skills like problem-solving and self-awareness.
They can feel emotions like humans do.
Dolphins are said to wear their hearts on their fins. According to the Orca Research Trust in New Zealand, bottlenose dolphins and orcas have been seen carrying dead calves in a show of grief.
This grief is represented differently when a member of the pod dies, depending on if their death is sudden or the result of a long illness.
They are not monogamous.
Dolphins do not mate for life. As extremely sexual animals, they mate with various partners over a year. They also don’t have a particular breeding season like whales do.
Dolphins are even known to have sex for pure pleasure and sometimes mate with dolphins of the same sex.
Dolphins can bite.
They always look friendly and cute, but dolphins are still wild animals and can be dangerous. They have bitten people and pulled them under water. They bite out of anger, frustration or fear and can lash out when people attempt to swim with them.
When begging for food, they can become aggressive when the outcome isn’t to their liking.
Male dolphins help each other attract females.
Dolphins studied in Shark Bay, Australia, have helped other dolphins, not out of friendship but to offer payback on a past favor helping them find a mate.
Theirs is a delicate dance of ensuring reproductive success; males sync their movements to capture the eye of females (think a street gang in a dance-off) and stay bonded to their male counterparts for life to ward off other rival groups.
We don’t know for sure why they jump out of the water.
While there is no way to know for sure why dolphins jump out of the water, scientists do have theories. They believe they do this to get a better view of the food around them, gain more ground in the ocean while putting out less energy and shed parasites from their skin.
They are also believed to non-verbally communicate with other dolphins in this way.
Dolphins communicate through a variety of methods.
As highly intelligent animals, dolphins can communicate with each other through verbal sounds and nonverbal means.
Scientists say they have a complex system of “speaking” to one another, which includes whistles, clicks and burst pulses.
Dolphins never completely go to sleep.
Dolphins don’t sleep an unconscious sleep like we do; they only allow one half of their brain to get some shut eye at a time. While one portion dozes off, the other allows them to breathe and keep an eye out for potential predators.
In fact, they only close one eye at a time when it’s lights out for that side of the brain!
Freshwater dolphins exist.
Dolphins aren’t only relegated to the oceans. In fact, there are four species of freshwater dolphins.
River dolphins look a little different than their ocean kin — they are a little more primitive with large forehead melons, large flippers and plenty of teeth. They live in Asia and South America and are critically endangered; their healthiest populations live in areas not yet exploited by humans.
Dolphins have body hair.
All mammals have hair, and dolphins are no exception. But it doesn’t last forever, falling out shortly after birth. Afterward, hair follicles can still be seen on their faces and snouts and stay visible for the rest of their lives.
Hair may be an evolutionary leftover or plays a role in communication with mothers and their calves.
Dolphins give themselves names.
Dolphins can recognize relatives in the pod. In fact, a study of bottlenose dolphins has revealed they have a signature whistle that can carry identity information.
They use these to reference themselves or to address other dolphins when communicating.
They are sometimes used by the military.
Due to their high intelligence and sociability, dolphins are one of the few mammals that have aided in military exercises for different countries. The U.S. Navy began their association with bottlenose dolphins in 1960, and it continues in some form to this day.
The animals aid in mine detection, object recovery, and search and rescue of naval swimmers.
Dolphins use tools.
In Shark Bay Australia, scientists have observed dolphins using other sea animals as tools to aid them in finding food. They cover their snouts with basket sponges and use them to find food by uncovering fish hiding on the seafloor.
They also use conch shells to scoop fish up (think nature’s silverware) and shake them into their mouths.
Their lifespan can be anything between 15 and 50 years.
It’s hard to say exactly how long a dolphin’s lifespan is — it all depends on their environment and the species of dolphin they are.
They generally live about 15 years, but some species like bottlenose dolphins can live 50 years or more.
Fish toxins make dolphins high.
Sometimes, you gotta cut loose, even if you’re a dolphin. According to Smithsonian Magazine, dolphins have been seen playing with and ripping apart the pufferfish to enjoy the toxic chemical it emits when threatened.
Afterward, the dolphins were said to be in "a trance-like state" while gazing at their own reflections.
There are over 40 species of dolphins.
The oceanic animal makes up 38 species of dolphin, and there are four river dolphin species. Eight of the 38 have the term “whale” in their name; these include the Pygmy killer whale, the long-finned pilot whale and the melon-headed whale.
Two dolphins even have both the terms “whale” and “dolphin” in their names — these are the northern right whale dolphins and southern right whale dolphins. Despite this, not all whales are dolphins.
The most endangered dolphin is the Maui dolphin.
Not only are they the smallest dolphin species, the Maui dolphin is the most critically endangered. With their black facial markings, short bodies and a Mickey Mouse-shaped dorsal fin, they are unusual looking, but you may never see one, as there are only 55 left in the world, and they all live off the coast of New Zealand’s North Island.
Their numbers have declined due entanglement in fishing nets.
Orcas are actually dolphins.
Killer whales fall under the order of Cetacea and the suborder Odontoceti, or “toothed whales.” However, they belong to the family under that suborder, Delphinidae, or oceanic dolphins.
With their more compact bodies, orcas look more like dolphins and are the largest dolphin species at about 32-feet long. However, in comparison to whales, they are on the smaller side (a blue whale can be more than 100-feet long).
Dolphins have natural radar.
Using the sounds they make, dolphins practice echolocation, a kind of sonar that bounces off the objects in around them. This allows the dolphin to determine how far away the object is and where it is.
Dolphins can detect objects using natural radar from as far away as 325 feet.
They give birth tail-first.
Dolphins only have one calf every few years (this amount of time depends on the species). To keep them from drowning, they usually come out tail first.
They then stay with their mothers for up to 18 months or until they learn to catch fish on their own.
Greeks believed dolphins were ‘hieros ichthys,’ aka ‘sacred fish.’
Dolphins were revered in ancient Greece; they believed Apollo (the sun god) took the form of a dolphin when he founded the oracle at Delphi at Mount Parnassus. Therefore, killing a dolphin was a death sentence for the perpetrator.
Ancient Romans also revered these animals — they were thought to carry souls to the afterlife and can be found depicted in art in Roman mummy tombs.
Breathing is not automatic for dolphins.
Dolphins have to make a concerted effort to breathe, even when they’re asleep. Each time they surface for air, they have to make an active decision to do so. This decision-making process is what keeps them from drowning.
For humans, on the other hand, breathing is an unconscious act.
Dolphins have no sense of smell.
Dolphins have a keen sense of hearing and can vocalize. Of course, they can also feel, but they do lack once sense — they cannot smell.
While they have olfactory tracts, they do not have olfactory nerves. They do taste, but only to a point — they can only really detect salt. (In that case, chewing seems a lot less important!)
Dolphins and whales play with each other.
Dolphins play with a whole host of creatures for various reasons, including humans. They do also enjoy the companionship of their much larger whale friends. In fact, bottlenose dolphins have been seen riding humpbacks off the coast of Hawaii.
Ken Ramirez, former VP of animal care and training at Chicago’s Shedd Aquarium, stated that what he saw in the images of this interaction could be described as play: “It is believed that the ‘surfing’ or bow riding that dolphins exhibit in front of boats may have had its genesis in riding in front or in the wake of big whales.”
Dolphins and porpoises are different species.
The terms “dolphin” and “porpoise” have been used interchangeably over the years, but they are not the same animals. Dolphins are the bigger of the two, with larger features including elongated “beaks.” Their teeth and fins are also differently shaped.
While bigger overall, dolphins are leaner than porpoises. Dolphins also “talk” more — they can make whistling sounds through their blowholes, while porpoises cannot.
They can’t see a full range of color.
Dolphins don’t see color the way humans do. While they live in the blue of the sea, they cannot see the color blue. Scientists believe they lost this ability millions of years ago, as the debris around them naturally tended to block out blue light.
While we can see a wider range of colors than they can, they are drastically better at seeing in murky water. Their eyes have 7,000 times the rod cells that the human eye does.
They are extremely fast swimmers.
A bottlenose dolphin can swim about 18 miles per hour. That may not seem fast, but they do make time when they travel — they can cover up to 100 miles a day.
While making their journey, they surface two to three times a minute to get much-needed oxygen, all the while jumping and flipping out of the water.
Unlike fish, dolphins are warm-blooded.
Dolphins are mammals; therefore, they are warm-blooded. They breathe through lungs, not gills and need to frequently surface for air.
As mammals, they give birth to live young as opposed to laying eggs. They also feed their calves with mother’s milk.
No two dorsal fins are exactly the same.
While you can generally tell what species of dolphin you’re looking at by looking at their dorsal fins — some are round, some are curved, and some lean to the side, for example — no two will ever look identical on different dolphins.
It is an identifier much in the same way fingerprints are.
A dolphin’s blowhole is actually a nose.
The dolphin’s snout is not its nose — over millions of years, thanks to evolution, its nose has migrated to the top of its head and has become a blowhole.
Because they do not have gills, dolphins need oxygen to survive. Their blowhole allows them to get it when they come to the surface of the water. When they go under again, it seals tightly, so that no water can get into their lungs.
Their supple skin regenerates about every two hours.
A bottlenose dolphin’s skin flakes away about every two hours, or 12 times a day. Their skin helps them move in the water at great speeds.
Shedding allows for new cells to come in and keeps their dermis smooth and aerodynamic.
Some dolphins can leap more than 20 feet into the air.
While dolphins are most often seen jumping just a foot or two above the surface, they're capable of impressive athletic feats. Dusky and spinner dolphins can both jump 20 feet or more into the air. That's roughly similar to leaping out of a pool and directly onto the roof of your house.
The name spinner dolphin actually came from their tendency to somersault as they jump.
Dolphins can recognize themselves.
Most animals can't recognize themselves in the mirror. If you have a cat that tries to attack itself when it passes its own reflection, that's why!
Dolphins, on the other hand, are bright enough to recognize their own face. They actually enjoy looking at themselves, too.
A two-headed dolphin was once found.
In 2014, a two-headed dolphin was found in Turkey. Conjoined twins are fairly common in humans, but it's very rare in wild mammals. Scientists estimate that less than 1 percent of small marine animals are born as conjoined twins.
Cases are also rarely discovered since most conjoined sea animals die quickly, due to difficulties feeding and reaching the surface to breathe.
A narwhal is a type of dolphin.
Did you know narwhals aren't fictional? They're 100 percent real, but they're extremely rare, and they're actually a type of dolphin. Because of their large, ivory tusks, their numbers have been dangerously reduced due to poaching, much like elephants.
The only narwhals still living reside in the Greenland Sea.
Dolphins can talk on the phone.
With their large, intricately folded brains, dolphins are extremely bright.
So bright, in fact, that they can communicate with each other via telephone through their unique language of squeaks, squeals and clicks.
It takes less inhaled water to drown a dolphin than a human.
One would think that a sea creature would be completely safe in the water, but that's not always the case. Although dolphins live their entire lives in the water, they're mammals just like humans. They have to come up to the surface to breathe, and if they accidentally inhale water, they can drown just like a person would.
Surprisingly, a human can tolerate more inhaled water than a dolphin can. Dolphins can drown after breathing in just one tablespoon of water, while humans drown after breathing in at least two.
Dolphin "midwives" exist.
Giving birth is tough on most animals, dolphins included. Since giving birth takes up all of a female's energy, she needs support from her pod during the process. Female dolphins often assist each other during childbirth, going as far as to help pull out the baby if it seems to be stuck.
Meanwhile, other members of the pod surround the expectant mother to keep her safe from predators until she and her calf are safe.
Dolphins never get the bends.
The bends, formally called decompression sickness, occurs when scuba divers rise to the surface too quickly. During dives, divers breathe in compressed air containing nitrogen. This isn't a problem at the bottom, and if divers rise slowly, the nitrogen is safely released through the lungs. If the process is rushed, nitrogen bubbles begin forming in the body, causing a case of "the bends."
Symptoms include everything from confusion and odd behavior to paralysis and death. Dolphins have an intriguing adaptation to avoid these unpleasant side effects of deep dives. They can collapse their ribcage completely, forcing air pressure (and excess nitrogen) out of their lungs and funneling it into a series of complex air chambers below its blowhole.
Their echolocation skills are more precise than human tech.
Dolphins' echolocation skills are virtually unmatched. They are far better at echolocation than bats, and their abilities can even rival man-made sonar equipment.
They can distinguish the difference in the distance of an object down to a quarter of an inch.
Dolphins have a special organ called the melon.
The rounded heads of dolphins are part of what makes them so cute, but there's an anatomical purpose for their oversized noggin. In addition to their large brain, dolphins have an organ called the melon.
The melon contains liquified fat that's used to transmit the clicking sound dolphins make into a focused stream of sound. These clicks can be heard by other dolphins from miles way.
Dolphins don't drink water.
If you were stranded on an island in the middle of the ocean, drinking sea water is the last thing you should do. Unlike fresh water, salt water will only lead to further dehydration. The same is actually true for dolphins.
For this very reason, they don't drink water at all, getting all the H2O they need from the food they eat.
Dolphins have the same number vertebrae as humans.
Dolphins, like humans and giraffes, have seven vertebrae in their necks. Yep, you read that right. Giraffes, with their 6-foot necks, have the same number of vertebrae as dolphins do. But wait, it gets weirder.
Saltwater dolphins have the first two vertebrae in their neck fused together for added stability while they're jetting through the ocean at top speed, but freshwater dolphins have unfused vertebrae for better maneuverings through winding rivers.
An average dolphin eats more than 30 pounds of fish daily.
A 250- to 300-pound dolphin eats around 30 pounds of fish per day. Many dolphin species are larger than that, however.
Bottlenose dolphins, for example, weigh up to 440 pounds and may need more fish to maintain a healthy weight.
Dolphins have conical-shaped teeth.
Since dolphins don't need teeth to chew, their teeth happen to be shaped more like a cone, lacking the sharp point that several other ocean animals have.
Plus, the number of teeth a dolphin has differs drastically between different breeds. For instance, a spinner dolphin can have up to 240 teeth, while a Risso's dolphin only has 14.
Dolphins can't swim backwards.
Dolphins, like sharks, can't swim backwards. They're just not built to propel themselves in that direction. This is why it's considered an emergency if a dolphin gets caught in a fishing net. It's often difficult for them to pull themselves free since they can't back up.
If the net is restrictive enough, it can keep them from rising to the surface for air, causing them to drown. Be careful where you cast your nets, people!