Battle of the Senses
Who has the most powerful senses - dogs or cats?
Animals’ sense of hearing is highly developed. Dogs and cats are able to hear ultrasonic sounds – these are sounds that are beyond the range audible to humans. We can hear up to 20 kilohertz per second while a dog can hear up to 35 kilohertz per second. The weird thing is that a cat, who I thought had less of a hearing ability than a dog, can hear an amazing 65 kilohertz per second.
Animals’ sense of hearing is highly developed. Dogs and cats are able to hear ultrasonic sounds – these are sounds that are beyond the range audible to humans. We can hear up to 20 kilohertz per second while a dog can hear up to 35 kilohertz per second. The weird thing is that a cat, who I thought had less of a hearing ability than a dog, can hear an amazing 65 kilohertz per second.
We explore the differences between cats and dogs.
The battle
Sight
Dogs
 Dogs are dichromats (they have a form of colour-blindness). Their colour vision can be compared to a human’s, but without red or green. One of the factors to take into consideration is that dogs have different eye shapes and dimensions, which means different eyes see in different ways. Dogs who have long noses have a very wide field of vision. This means that they can see a very wide piece of space, almost like a panoramic view. This is because they have something called a ‘visual streak’ which is the elongated area of light sensitive cells on a dog’s retina. Dogs with short noses have area centralis instead of a ‘visual streak’. Area centralis is a central patch with three times the amount of nerve endings. Instead of giving them a wide field of view, this gives them the ability to see in a lot more detail – more like a human. Sight hounds (hounds that primarily hunt by sight and speed), have a field of vision up to 270 degrees. Humans only have a 180 degree field.
Cats
A cat’s vision is much superior at night. Cats are nocturnal animals, hunting by night mostly while dogs are diurnal (more active in the day). Both dogs and cats have something called a tapetum lucidum, which is a reflective layer behind the retina. Although they both possess this, Paul Miller, a clinical professor of comparative ophthalmology, believes that a cat’s ability to see at night is better than a dog’s. The tapetum lucidum enhances the cat’s ability to see in low light but reduces her ability to see when there is a lot of light. In very bright light her iris closes narrowly improving her depth of field. Average cats have a field of view of 200 degrees.
Scoreboard
This one is tricky, although cats can see better at night, some dogs have a wider field of vision which ultimately means the species can see more. Sorry, kitty cats.
Dogs: 1 Cats: 0
Hearing
Dogs
A dog can hear any sound from 40 Hz to 60 000 Hz, compared to humans who can only hear 20 to 70 Hz. Dogs can also hear sounds as low as 16 to 20 Hz and as high as 45 kiloHz. They can also pinpoint the exact location of the sound because of the mobility of their ears (which have 17 different muscles in them to move them). However, dogs with floppy ears do not hear as well as dogs with fox-like ears.
Cats
Cats have a similar range of hearing to a human on the low end of the scale. On the other hand they can hear high-pitched sounds that go up to an amazing 64 kHz. When a cat hears something her ears will rotate and swivel to pinpoint the exact location of the sound, just like the dog.
The loudest sound ever described by humans?
Krakatoa volcano in Indonesia, exploding. The sound was heard up to 4828 kilometres away.
Scoreboard
Cats are better at hearing.
Dogs: 1 Cats: 1
Smell
Dogs
Some dogs like Bloodhounds are bred especially for their keen sense of smell. Mammals have something called smell-sensitive cells, which tells you how well, or how bad they are able to smell. Dogs have an amazing 220 million smell-sensitive cells on an area the size of pocket handkerchief compared to 5 million in humans on the size of a postage stamp. Dogs can also sense odours 100 million times lower and 40 times larger than humans.
Cats
Cats have twice as many smell-sensitive cells in their noses than humans do. This means they have about 10 million cells which is about 14 times stronger than a human’s. Cats also have something called a vomeronasal or Jacobsons organ on the roof of their mouth. When a cat wrinkles her muzzle, lowers her chin and lets her tongue hang, she is opening the passage to this organ to enhance her sense of smell. This is called gaping.
Scoreboard
Dogs have more smell-sensitive cells, one more point for them.
Dogs: 2 Cats: 1
Touch
Dogs
A dog senses touch through his whiskers, his lips, paws, pads and nasal area. His whiskers are deeply rooted into the skin and the ends of them are covered in delicate nerve cells. A dog’s whiskers are not as important as a cat’s. A dog also has touch-sensitive hairs called vibrissae which are able to sense airflow. These hairs are on the muzzle, below the jaw and above the eyes. His entire body is covered in touch-sensitive nerve endings. His most sensitive area is along his spine towards his tail.
Cats
Cats have about 24 movable vibrissae –specialised hairs used for sensing touch. They have these hairs over their eyes, on their chin, on their inner wrists and on the back of their legs. These hairs give cats an extraordinary sense of detailed information about air movements and vibrations. This enables her to know where obstructions are without actually seeing them. Cats also use their whiskers to hunt. When researchers used stop motion photography to look for how a cat uses her whiskers, the picture revealed the cat using them to detect where the prey is. The picture shows the whiskers creating a basket like shape around her mouth in order to detect the prey. It is also thought that cats rely on their whiskers in dim light to focus on close objects.
Scoreboard
Cats definitely take this point.
Dogs: 2 Cats: 2
The deciding sense!
Taste
Dogs
Dogs have a lot fewer taste buds than humans do, having approximately one taste bud for every six that we have. They can taste the difference between sweet, salty, sour and bitter but dogs rather use their sense of smell than taste. They gather more information this way.
Cats
In 2005, scientists tested the cat family to see if they had the gene that allows them to detect sweetness. The results revealed that they did not have it. Another protein T1R3 (another gene) is also present in cats but it is inactive. Some scientists believe that this is the root of their extremely specialized evolutionary niche as a hunter. This modified sense of taste causes them to ignore some plants with high sugar content and rather opt for a high protein carnivorous diet.
Scoreboard
Even though this is a weak sense for both species, cats lose because they can’t taste some things at all. Another point to the dogs.
Dogs: 3 Cats: 2
 Dogs have come out tops in the battle of the senses! With their much wider range of sense ability they are able to do a lot more general things while cats are very niched and specified for their exact needs. Dogs are the better generalists, almost like ‘Jacks of all trades’, while cats the better specialists. The battle between dogs and cats will never end, but, in this very generalized case, every dog has his day!
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Source: wikipedia.org
Text: Kerry de Bruyn
Published : Thursday, December 17, 2009 - 09:23
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