Are felines carnivores?

I would hope and expect that 99.9% of the world's population know that felines are carnivores. They are meat eaters. It is stronger than that. They have to eat meat because they are what are called 'obligate carnivores'. They are obliged to eat the flesh of animals due to their evolution. They are specialists as genetic mutations have lead them to becoming dependent on the flesh of animals.

But it is not as straightforward as that. Although evolution dictates that they have to eat the flesh of animals they do also eat the stomach contents of the animals that they kill. The stomach contents will be vegetation because they prey upon animals that feed on vegetation i.e. herbivores. So felines also eat vegetation.

A lot of commercially prepared cat food is based on polluted carcasses of animals and therefore arguably plant based foods + added nutrients is better in quality. Image: MikeB.

Also, we know that domestic cats sometimes eat grass. That is a plant and the plant is not an animal! And therefore felines are not exclusively carnivores. They eat grass, it is believed, because grass contains folic acid which is missing in their diet. Folic acid plays a role in the production of haemoglobin, the oxygen carrying protein found in red blood cells. Although there are many theories about why cats eat grass.

The snow leopard specifically eats a certain bush i.e. vegetation and it is my theory that they do this because it increases the amount of oxygen in their bloodstream. It therefore enhances their ability to live at high altitude. I stress that this is my theory because no scientist has studied this. Although I have an article about the snow leopard being partly vegetarian! You can click here to read that article if you wish. Note: In Pakistan more than 22% of faeces of snow leopards inspected contained plant matter and in Ladakh (in the northern Indian state of Jammu and Kashmir ) more than 50% contained vegetation including willow and Myricaria bushes (Myricaria germanica)

Another point worth making about felines being carnivores is that there is a trend nowadays towards eating plant protein rather than protein from the muscle of animals. This is to help curb climate change. Therefore manufacturers have started to sell plant-based dry cat food for domestic cats. On the face of it this is not going to work but the manufacturers add the nutrients necessary to make the food balanced for domestic cats. You can make your own mind up about it but I believe that as long as the essential nutrients are present at a microbiological level then the food is nutritious.

There is a caveat to that last statement and that is this. A recent study decided that if you want to curb the hunting of the domestic cat (and a lot of cat owners do) you should feed them with a high quality grain-free entirely meat-based wet cat food. You should find that they hunt less. It appears that "complete and balanced" wet cat food normally available is not quite as complete as it should be and therefore the domestic cat decides to hunt mice in order to supplement what they might consider to be a deficient diet from their perspective.

This is a novel approach to curbing domestic cat hunting. Further work is needed on this. But domestic cat wet cat food and dry cat food can be quite deficient and too far removed from a natural prey animal such as a mouse. Dry cat food is highly artificial for example. It's convenient but there are deficiencies with it. And there's too much plant material to bulk up cat food and to keep the price down. But hundreds of millions of cats fed on this type of cat food and they survive on it but we don't know how much health damage it does to them in the long term.

To return to the question in the title: are felines carnivores? Yes, is the answer because evolution dictates that. They have become highly specialised due to their evolution and dependent upon a meat-based diet. In the wild they satisfy that evolutionary demand by preying on wild animals and sometimes livestock (e.g. the mountain lion). But in the human world, people have found ways to feed the domestic cat with plant protein and dry foods containing grain which is less than ideal.

How can cats jump so high?

The answer to the question is all about mechanics and muscles. The domestic cat and indeed the wild cats have lots of fast-twitch fatiguing muscle cells. These cells are designed to propel the animal quickly; to allow the animal to accelerate quickly, but they're not very good at prolonged effort because they tire. The cat is a sprinter rather than a long-distance runner such as the African wild dog, mule or horse.

The puma is perhaps the best jumper of the large wild cat species. Image: PoC.

The second reason is all about the mechanics, the leg bones, particularly the hind leg bones of the domestic cat which are long. The muscles working to move these long levers allow the cat to jump so high. The concept of long levers applying a stronger force than short levers can be seen in bolt cutters. They have long handles. And if you want to unscrew a nut which is rusted in or very stiff, if you use a long spanner you will be more successful than if you use a short one.

And of course the hindquarters of a domestic cat and the other cats such as the mountain lion are very powerful. When these muscles contract quickly combined with long levers the cat is propelled forward either to attack an animal or leap upwards. 

There is also the matter of power-to-weight ratio. The heavier cats will be less good at jumping than the lighter species. The lion, for instance, is not a great jumper relative to the leopard which is considerably lighter.

The lion is built to grab hold of large prey and subdue them. This is why their arms (forelegs) are immensely strong much like the tiger's. This power-to-weight ratio is best seen in the caracal which is a medium-sized wild cat species. This is the cat that jumps the highest. They have an ideal power-to-weight ratio. The picture below is of a caracal catching or trying to catch a bird (or an object thrown by someone to simulate a bird) in flight:

Caracal leaping to catch a bird in flight. Picture in public domain.

All the medium-sized cats are probably more adept at jumping vertically than the big cats. There is too much inertia to overcome in a big cat and the power-to-weight ratio is not as good as for the smaller species.

And one of the factor which may play a role as to why cats can jump so high is the floating shoulder. The forelimbs are connected to the rest of the body by muscle. The cats clavicle floats and is anchored by muscle. This allows cats to lengthen their stride and it enhances the range of motions that cats have. This indirectly helps a cat to jump well.

The cat's foot is elongated and it looks like a leg bone but it isn't. At the end are the toes and cats walk on their toes because they are digitigrades. I would argue that this also adds to the leverage that a domestic cat has which once again supports the ability to jump high and horizontally over long distances.

The video on this page is of a female F1 Savannah cat whose name is Magic. I don't know whether she is alive still but at the time she was the tallest domestic cat to the shoulder in the world. Savannah cats of this type i.e. first filials have a serval father and the serval has the longest legs to body size of all the wild cats. That's why the F1 Savannah cat is such a fantastic upwards jumper. Once again it's about leverage using long levers.

Domestic cat has a slow brain but rapid reflexes

I don't want to malign the domestic cat because I love the domestic cat. I'm trying to be realistic. I say that the domestic cat has a slow brain to which I could add "relative to the normal human brain". By this I mean that when the domestic cat has to process responses to human requests they do so more slowly than for humans. No big deal and nothing unusual there. There is no urgency in their response but there is an incredible speed in their instincts.

Domestic cat looks disdainfully at photographer. Photo: Pixabay.

Let me try and give you an illustration. You have trained your cat to come on your call. Your cat knows their name and they respond to being called by their name. But they take, relatively speaking, quite a long time to respond sometimes. This is why there was a splurge of articles not so long ago, by Internet journalist, stating how domestic cats don't respond to being called to come, but if they do come they do so disdainfully and with some reluctance.

I even recall a study on this which supported this notion. But in my opinion it is not a question of domestic cats refusing to come on being called, it is a question of the time it takes for them to process the call and to figure out that they should come. They look rather blankly and aimlessly during this time. Then off they go.

Conversely, in stark contrast, their natural hunting instincts are super rapid. Their instinct to chase prey emerges incredibly rapidly. If, for example, you wave your hand around your cat's head and he or she happens to be one of those domestic cats who likes to hunt and is perhaps on the young side, he will probably have a swipe at your hand within a nanosecond.

The rapid instinctive movements of domestic cats is renowned. This is why when handling a cat, even one you have lived with all your life, you have to think about these instincts and how they will play out in the mind of your cat. The domestic cat's wilder side, as we know, is right near the surface. It can be motivated, triggered into action with the right signals from their human companion.

The moral of this article is that (1) people should be patient when asking their cat to do something. They may understand but they may take their time in responding and (2) people be aware of the wild cat beneath the domestic one. It comes out in a flash and their instinctive, inherited hunting movements triggered by fast moving objects and the right sounds spring into action without notice. It is wise to be aware of it and respect the cat for these fantastic skills.

And don't expect a cat to be like a human family member even if you regard them as family members as many people do. This is where the idea of cats' not responding to a call comes from. They expect a human response or a dog's response. Dog's repond faster than cats because it is instinctive to them as they are pack animals.

Why cat hiccups dilates the eye's pupil

Cats' eyes dilate when they hiccup. pic.twitter.com/9eAQ5h06iQ

— Science is Amazing (@AMAZlNGSCIENCE) November 19, 2020

This is an embedded video and sometimes they stop working overtime. If that has happened I apologise but I have no control over it.

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This is an interesting little video which repeats itself. I am sure that it has been all over the Internet. However, I have just spotted it. The cat hiccups and immediately afterwards the pupil of the cat's eye opens slightly because the muscles of the iris relax. That is my theory. The pupil of the cat's eye is made smaller when the muscles of the iris are contracted. It requires muscular effort for the pupil to be in a contracted state. When the cat hiccups the purposefulness of that process of contracting the muscles of the iris is temporarily stopped as the hiccups distract the brain. Therefore the pupil enlarges and the eye becomes more dilated. That of course is a personal theory which I simply worked out because you cannot find the answer on the Internet. It makes for an interesting little video on a different level namely that you can see how the iris works and the pupil forms a slit. This slit pupil is very important to the domestic cat because it allows the animal to see in bright light and in extremely dark conditions as well. The slit aperture of the cat's pupil work sin harmony with the cat's eyelid which goes over the slit like a blind at the window of a person's home. The slight pupil also enhances a cat's depth perception.

Why do domestic cats have vertical pupils?

Domestic cats have vertical pupils for two reasons:

1. On a scientific level it is said that a vertical pupil provides better depth perception which allows a domestic cat to measure distance better and/or focus on prey better. A scientific study by researchers at the University of California, Berkeley, decided that with vertical slits, predators see vertical lines behind the point of focus quite sharply but horizontal lines at the same distance are blurred. This allows them to have a greater ability to pinpoint prey animals.
2. The vertical pupil in conjunction with the eyelid allows the cat to restrict light to the retina more effectively than a circular pupil under bright light conditions. The eyelid passes down the vertical pupil like a blind which, to use a photographic term, stops down the lens to a smaller aperture than normal. This is needed to protect the retina which has a mirror-like film behind it (the Tapetum lucidum), which reflects light back to magnify the capture of light so that they can see better under dark conditions.

Photo in public domain.

The reason why newborn kittens don't squabble over nipples

The picture is from Wikipedia Commons. The mother is Sugar. She gave birth behind the TV as it was warm. Her kittens were named: Channel 3, Channel 5, Cable 8, Circuit Overload!

Newborn kittens do not squabble over their mother's nipples because each one is labelled distinctly by subtle differences in smell. As Desmond Morris says, each nipple is labelled as if they were school lockers. I think it's a wonderful analogy. It highlights both the sophistication of the domestic cat and the wonderful sense of smell with which they are born. If you remove the distinguishing fragrance of a mothering cat's nipples, the kittens become disorientated and confused and start squabbling. Nature found a beautiful way to allow the domestic cat family to live in harmony from the get go. I love the thought of that.

How much blood is in a cat's body?

I'm referring to the domestic cat. The domestic cat has about half a pint of blood inside the body that passes around their body once every 11 seconds. This is about 250+ milliliters (8.5 oz). The cat's heart beats at 110 bpm to 140 bpm. This is about twice the human heart rate. 

Photo: Pixabay

The cat's circulatory system comprises the heart, a network of arteries and veins, the spleen and a reservoir of blood. The blood goes from the heart to the lungs changing colour from blue to crimson. Iron atoms in the haemoglobin molecules of red blood cells discharge carbon dioxide and latch onto oxygen molecules which have been inhaled by the cat.

Red blood cells have a lifespan of about 2 to 6 weeks. They are produced in bone marrow on a hormonal signal. There are 270 million haemoglobin molecules in every red blood cell. Each molecule of haemoglobin contains four atoms of iron. Each molecule of haemoglobin can transport over 1 billion molecules of oxygen.

See a page on cat anatomy.

The end of a cat's nose should be dry under normal conditions

The end of a cat's nose should be dry under normal conditions and good health in my considered viewpoint subject to condensation (see below). Over the years, there has been quite a lot of discussion about the end of a domestic cat's nose and whether it should be dry or wet or damp or whatever else it should be. I think people are getting confused about it.

It depends upon the external conditions. If you take an indoor cat who is healthy and on the assumption that the ambient temperature in the home is comfortable for human and cat then the end of that cat's nose should be dry. If that cat then goes outside into cold winter weather the end of her nose may become damp because of condensation from her damp breath forming on the end of her nose.

Temporarily her nose will be damp but this is due to physics. It has nothing to do with her health. If she is unhealthy with a cold then she may have a runny nose so the end of her nose will be damp. If she is a little confused or stressed she may engage in what is called "displacement activity". This may entail her licking the end of her nose repeatedly. This would make her nose damp.

Dr Yuki Hattori, a well-known Japanese veterinarian, in his book What Cats Want states incorrectly in my view that the end of a cat's nose should be damp. I genuinely believe that he is confused about this. He argues that it is damp so the cat can smell scent molecules more effectively. That I just cannot believe. Yes, certainly if scent molecules are damp they can be smelled more effectively but this is not a reason why the end of a cat's nose should be damp.

My cat's nose is dry. I've just touched it. He's inside with me in dry, warm conditions. His nose reflects those ambient conditions. I would challenge anybody who reads this (and they will be very few people who do!) to carry out their own test and touch the end of their cat's nose. You can then tell me in a comment whether it is dry or wet or something in between such is damp.

To reiterate, the dampness or dryness of the end of your cat's nose depends upon a range of circumstances and conditions one of which is the ambient air temperature. You cannot discuss the end of your cat's nose in isolation of ambient air temperature and a cat's health. But the default situation should be a dry nose leather in my view. The phrase "nose leather" is a cat fancy term meaning the end of the cat's nose which looks a bit like leather. As the flat bit out ofwhich two nostrils protrude.

Why are domestic cats so small?

Because they are descended from the North African wildcat, a cat of similar proportions and appearance even after about 10,000 years of domestication. I suppose you might ask why was the North African (African-Asian) wildcat domesticated?

Comparison domestic and wildcat ancestor.

It is because the place where they were first domesticated - the Fertile Crescent (in the area of Syria) was suited to farming and it so happened that this wildcat was present in that landscape. The cat and farmer met to mutual benefit and the rest is history as they say. 

The North African wildcat has a relatively nice temperament suited to domestication. They kept the rodents down and the farmer had a working cat and some company and fun. This happened around 9,500-12,000 years ago it is believed.

There are other small wild cats who are also suited to domestication to various extents e.g. the margay, but it just happened that the North African wildcat got their first perhaps because 10,000 years ago the Middle East was a developing and active area for farming. 

Farmers would have encroached onto the wildcat's territory forcing them together. There may have been conflict between human and cat but some farmers liked their presence for their rodent killing habits.

There must have been the very first domestic cat. At that time there was a single domestic cat in the world. Now there are around half a billion domestic and feral cats.

It is worth arguing that the question is incorrectly formulated as what is 'small'? There are smaller animals than the domestic cat and there are larger ones. They are small compared to us. It might be argued that the domestic cat is somewhere in the middle range of animal size. 

Therefore it could also be argued that they are not small. I think perhaps the reason why the question has been formulated is because the questioner is comparing the cat to the size of humans. Therefore relative to humans the domestic cat is small. That is not a good reason to ask, "Why our domestic cat so small?"

Do cats have a collarbone?

Cats do not have a collarbone. This anatomical peculiarity allows a cat to fit through any opening which is the size of his/her head. A cat's forelimbs are attached to the shoulder by free-floating clavicle bones.

Can a cat see in pitch black?

The answer to the question, "can a cat see in pitch black?" must be NO because you need some light to impinge upon the retina for the retina to then send a signal to the brain. Pitch black means absolutely no light. Despite the fact that the cat's eyes are more sensitive to ours and their vision at night is excellent, they cannot see in total darkness. No animal can.






Light reflected from the cat's retina. A typical nighttime scene. Hence the phrase "cat's eyes" to mean the center line road markings by reflective glass marbles invented in Yorkshire, UK.

Do Cats Fart?

Domestic cats do fart but, in my experience, it is silent. Put it this way, all the cats that I have looked after have passed wind at sometime or other but not very often and I've never heard the process taking place.



There is no reason why a domestic cat should not pass wind just like humans. Their anatomy is very similar to ours. In fact, I am sure that most cat owners have smelt the effects of their cat passing wind. If it happens a lot I would ask questions such as whether your cat might be ill or whether the diet is correct. A cat should not pass wind regularly or to the point where it becomes an issue or noticeable.

The reason why I have written this very short post is because people search for the phrase: “Do Cats Fart?". I'm not sure why people are so interested in that particular aspect of the domestic cat's anatomy but there it is. It just goes to prove that the domestic cat is very similar to the human in many areas.

Cat Ears Warm to Touch

The reason why the ears of a cat are warm to the touch is because the blood vessels are very near the surface.  The blood circulates around the body. The body temperature of a domestic cat is 100 to 103°F.  This is 37.7°C to 39.4°C.  

This is quite a warm temperature and when you touch the earflaps of a cat you more or less feel this temperature less a certain amount because you are not in direct contact with the blood and the blood will cool temporarily as it passes through the flap.

The fact that the ear flap (pinna) is so fragile and thin and that the blood vessels run near the surface within the flap, provides an opportunity for a veterinarian and a cat owner to administer medication via the ear flap.

Certain medications placed against the ear flap are absorbed into the bloodstream. One such medication is transdermal Methimazole.

Transdermal means through or across the skin. You can see a video on this page about the application of this medication which is for feline hyperthyroidism.

Cat Ear Anatomy – Henry’s Pocket – Why it Exists

Cat Ear Anatomy – Henry’s Pocket – Why it Exists

Have you noticed that rather strange secondary ear flap attached to the main ear flap (the bit you see) in your cat? If you look carefully you see what is described as a "pouch" or "pocket" at the lower part of the ear flap (scientific name: pinna). The photo shows it:

Everyone says that this pouch or pocket serves no purpose. I disagree - but cautiously - because I am not sure. However, it is a part of the anatomy of a cat's ear and nature wouldn't have allowed it to evolve without a reason, I believe.

All evolution is about survival. I therefore concluded that Henry's Pocket or the "feline cutaneous marginal pouch" (as it is scientifically referred to) exists to enhance hearing of high frequency sound produced by its primary prey: the mouse.

The only reason for enhancing hearing is to improve the chances of survival which can be translated into improving the chances of catching prey. Domestic cats are wild at heart.

Therefore having researched "pinna notch" I concluded its presence was a modification of that. What is pinna notch?

It is the inference and consequential reduction in strength of sound waves of a certain frequency as they hit the ear drum because some sound bounces around the ear before entering the ear canal and impinging upon the ear drum, while some sound enters the ear drum direct. The later is a direct path and the former is the longer path. The sound that has the longer path interferes with sound of a different frequency which takes the shorter path causing it to be attenuated (reduced in volume). Henry's pocket creates an area where sound bounces around before exiting to the ear drum at the end of the ear canal.

This allows high frequency sound to stand out more and become more noticeable, which aids the cat in detecting the sounds that rodents make which are high pitched (ultrasound).

That is the theory and it is only a theory. The link at the top of the page takes you to a similar article which explains it differently! It is a rather complicated theory. No one else has proposed this.

Cats have better hearing than dogs and much better than ours. There range of hearable frequencies is much wider. Cats are superb at detecting and locating rodents through sounds.

Note 1: please see the comment: Anonymous 16 January 2016 at 07:15 which provides a very credible reason for the existence of this anatomical ear feature.

Note 2: this is a cross-post because I think the idea deserves to be posted on more than one website.

World’s Ugliest Cat?

World’s Ugliest Cat?

Ugliest cat on the planet?

Is there such a cat? It is unfair ;) Although he is pretty ugly. But a cat this conventionally ugly can actually be attractive to many people because his appearance is special and different. He's more cute than ugly. That is probably the consensus of opinion.



This cat must carry a genetic mutation similar to the one that creates the Sphynx and Don Sphynx. In fact in appearance "Uggs" is more like the Peterbald from Russia which is often a partially bald cat but not in this way. The mane of hair needs grooming. Perhaps they leave it deliberately ungroomed to enhance the ugliness.

Safer Bicycle Inspired by Cat's Whiskers

Students in Long Beach, USA wanted to make cycling safer in the city.  They wanted it to be the safest place for a cyclist.  One element of safety for a cyclist is an adequate amount of space around the cycle.  They wanted to design a bike or an accessory for a bike which addresses the problem of adequate space for a cyclist and they found the answer in nature, in what they refer to as bio-attributes. In observing animals they found the answer in whiskers.

These need not be the whiskers that belong to a domestic cat but the sake of this post I will refer to a cat's whiskers and in any case a cat's whiskers are the best!  They are a remarkable item of anatomy.  They are incredibly sensitive because of a heavy conglomeration of nerves at the base of each whisker which allows the cat to detect small changes in air currents surrounding the whiskers which in turn allows the cat to detect what objects are there in dark conditions because the air currents move around objects and are disturbed by objects.  The whiskers allow a cat to read the terrain without actually seeing it.

A cat's whiskers are like the fingers of a hand in that they can feel the cat's prey and help guide the cat when killing prey in dusky conditions at dawn and dusk.  It is said that the cat's whiskers allows the cat to feel the position on the nape of a small mammal's neck where the cat is to insert his canine teeth to sever the spinal cord.

Inspired by the sensitivity and functionality of whiskers the student engineers came up with whiskers for bikes.The product is called vibriSee and essentially it allows the cyclist to signal to other road users how much space the cyclist requires.  They look like somewhat like cat's whiskers as you can see in the photographs on this page.

See the video from which these screenshots were taken.

Article by Michael Broad

Cat Anatomy Quiz

A challenging cat anatomy quiz! Well actually some questions are challenging and some are just baffling! But, that said, some are easy. They are all about a cat's anatomy. The cat has an amazing anatomy which, in fact, is quite similar in many ways to ours. The most amazing bits of cat anatomy are concerned with the cat's senses. This is an animal with acute senses and a flexible skeleton supported by quick acting muscles (there's a clue there to one of the questions...). A cat's anatomy is designed for predation. Is this the world's best predator? Answers?...See mine here.

See the results from visitors including yours if you did the quiz.

Why are cats' tails so long?

Are cats tails so long? It is all relative and subjective. But some cat's tails are longer than others. If the cat is a domestic cat there is no pressing reason why his or her tail should be longer than that of another cat other than the physical characteristics of the cat as dictated by his genetic makeup (genotype). There will be no demanding functional need for a long tail.

The situation is different for the wild cats. You will see long, thick, heavy and well insulated tails on cats that do a lot of high risk climbing and maneuvering. Wild cat species that come immediately to mind are the snow leopard, margay and clouded leopard.

I believe what needs to be stated is that the length of a cat's tail has been dictated by evolution over millions of years. The tail is a perfect length for the function that it needs to perform which as mentioned below is to help a cat balance when performing manoeuvres which are tricky at high elevations. For example, walking along a branch of a tree for a domestic cat or a tree-dwelling wild cat species (margay). Because evolution has a sort of perfection about it you cannot state that the tail is so long or too long or too short. It is a perfect length for its desired primary function.

RELATED: Cat Tail Up Position: Meaning and Origin.

A secondary function is as a signal to another cat that the approaching cat is friendly. This is when the tail is placed in an erect position called "tail-up". Another secondary, inadvertent function, is that it signals an indecisive mind. When the mind flicks between two possible decisions the tail follows as if metaphorically speaking it is keeping the cat's mind in balance.

Snow leopard tail - cropped image to highlight tail
You won't see a better tail. Photo: by Marit & Toomas Hinnosaar

The snow leopard has perhaps the most impressive of tails. It is far longer and thicker than anything seen on a domestic cat relative to the size of the cat. This is because the snow leopard spends a lot of its time on 40 degree rocky slopes. And the tail is needed to assist in balance. The other two are tree dwelling cats.

This requirement applies to all cats. The cheetah, a ground dwelling cat uses its tail for balance in maneuvering on the ground when chasing prey.The serval has a relatively short tail. The serval is very much a terrestrial cat.

Domestic cats use the tail for balance too, but also for body language communication. See for example: Tail up.

What are cats' tails for?

What are cats' tails for? Two uses come to mind immediately.  Cats' tails are used for balance. In the domestic cat this use is somewhat redundant. For wildcats it is very much alive. Many wild cats are tree dwelling such as the margay and clouded leopard. These cats have long tails. Tails that are used for balance are also frequently very thick. I am thinking of the snow leopard that lives on 40 degree rocky inclines where excellent balance is paramount.

Although the domestic cat does not need the tail for balance as much it has developed another use of the tail, a form of visual communication through body language.

The wagging tail means that the cat is in mental conflict (out of balance mentally and not physically). This happens when he or she is uncertain about what to do.

The domestic and feral cat also uses the tail in the upright position to signal a friendly greeting. The tail position is used as a form of body language.

Cats that have bob tails or shortened tails are at a slight disadvantage. The bobcat comes to mind for the wild cats and the Japanese Bobtail is one example of a purebred cat without a normal length tail.

The bobcat is a ground hunter and probably does not need its tail for balance when chasing prey as much as the cheetah which is a much faster cat (max 64 mph compared to about 40+ at a guess for the bobcat).

How do cats' eyes work?

They work the same as ours with some differences. As for our eyes, light is focused on the retina by the lens.

The aperture that controls the amount of light entering the eye is called the pupil. The iris is that part of the eye that adjusts the pupil's size. The cornea is the transparent front of the eye.

The retina contains the light sensitive nerves that transmit the information received via the optic nerve to the brain.

The two differences are:

• Behind the retina at the rear of the cat's eye is a reflective layer called the tapetum lucidum. It reflects light back to the retina to boost the amount of light that the retina receives. The resultant increased sensitivity allows the cat to see in dark conditions for hunting. Cats prefer to hunt at dawn and dusk. The reflective layer is so effective that you can see it working at night when light reflected from it comes out of the eye.
• The extra sensitivity that the tapetum lucidum brings to the cat's eye results in the eye developing a greater facility to restrict the amount of light entering the eye in bright light. The human pupil is circular while the cat's pupil forms a slit when closing. The eyelid can then be used as a shutter that passes down the slit to further restrict the amount of light hitting the retina.

Showing reflected light from the cat's tapetum lucidum
Photo by Tobyotter

Showing slit eyes - Photo by Elsie esq.

See feline eye disease