Facts and Information
Dolphins are very intelligent, and they seem to be able to do plenty to help themselves survive in a variety of circumstances. A big part of that is their great senses that they can rely on to help them out. Vision is very good for dolphins, and they have the ability to see both in the water and out of it. This allows them to move around in the water with ease and to avoid dangers. Some of the dolphins that live in rivers that are murky and muddy can even see well in them.
One of the dolphin species though, the Indus Dolphin, is believed to be blind. This particular river though has very little light that is able to ever get into the water because of the types of sediment found here. However, these dolphins just seem to rely more on their other senses so the lack of vision isn’t a problem for their survival.
Hearing is amazing for dolphins, and it is believed they can hear up to 10 times better than humans can. They have very small ears that are behind the eyes so many people don’t give their hearing much of a thought. They can hear both in the water and on the surface of it. They don’t just use their ears to hear though, they also rely on their lower jaw region. It is able to send sound to the middle ear through the melon which is in the head and full of fat.
The melon is a big part of the overall process for hearing and for echolocation that the dolphins use. They have antennae like reception through their teeth that allows them to get information regarding sounds. They use echolocation to assist them with finding objects, determining their size, and more. There are plenty of questions unanswered about the complexity of echolocation. However, it is known to be one of the major resources that dolphins have to rely on.
Touch is also a common sense that dolphins use for their social needs to be met and more. They have free nerve endings around the skin so they are quite sensitive to touch. They also seem to be very sensitive around the pectoral fins and the snout. They use their sense of touch to form bonds with the humans as well as within their pods. The stimuli from touch can be very powerful and that could be why some dolphins are so eager to learn and to do what humans request from them.
According to research, dolphins don’t have a sense of smell as they don’t have nerves or olfactory lobes to do so. However, they may taste the water to be able to find out what is around them and to determine what food sources they will pursue when they have options. The fact that they do seem to prefer certain fish species over others strongly indicates that they do smell somehow. Since there is really no other explanation for why they would taste the water, this theory could have some merit to it.
Very few dolphins have hair other than just a few that they are born with but they often fall out. Yet they do have hair follicles and that could be part of their senses as well. The Boto River Dolphin does have hair but they don’t have very good vision. Perhaps this helps them to make up for it and balance it all out.
It is possible that dolphins have a magnetic sense as well. This would enable them to use the magnetic field from the Earth to assist them with navigation and with orientation. This could be why some dolphins are able to successfully migrate long distances and find their way back to their natural habitat. There have been some studies involving Humpback Whales that show they rarely move out of the magnetic pull from the North when they are migrating. There is still more research that needs to be done though to confirm such ideas.
There is no doubt that the senses of a dolphin are key to them surviving. Evolution is believed to be part of that survival with the process of echolocation developing to help them. The information that is used through a combination of senses enables dolphins to evaluate their surroundings and to be safe. It helps them to keep a distance from dangers such as sharks or colliding with boats.
They can also use their senses to help them be able to find food and to socialize within their pods. This is why environmental factors are so important to take a close look at. For example, exposure to chemical pollution in the water can reduce the sensitivity that dolphins have to touch. Noise pollution from boats, sonar, and more can cause dolphins to lose their hearing over time.
