Big cats are one of our planets most successful groups of predators which have existed in one form or another (Felidae) for 25 million years. Today they are found on every continent except Antarctica, living in environments ranging from dry deserts and freezing tundra to tropical rainforests and lush grasslands. The tiger, lion, jaguar, leopard, snow leopard, cougar, clouded leopard and cheetah constitute the big cats but a further 29 smaller species make up all wild cats.
Big cats are morphologically designed to be the ultimate land predator—no other animals can match their speed, agility and weaponry for their size. Furthermore, they share a very particular set of skills, skills that they have evolved that make them a nightmare for animals like deer, antelope and bovines (cattle-like species). Let us present to you the definitive big cat cookbook for taking down the perfect prey.
The pelage (fur) of big cats is one of their most striking features and is critical to their hunting success. Colouration and markings prevent a hunting cat from being seen while waiting in ambush or stalking prey. Some species are camouflaged, like the cryptic colouration of the lion or cougar whereas others like tigers and leopards have disruptive colouration where a bold pattern against a paler background colour helps the cats to disappear in dappled light. Melanism is common in some big cats such as the black leopards of Southeast Asia where their black colouration provides camouflage against the shaded forest floor. Pelage also provides insulation which is particularly important for big cats that wait in ambush in cold climates such as snow leopards and tigers. For these cats maintaining muscle warmth before an attack is critically important for a successful kill.
Big cats have superior senses. Many big cats are nocturnal or crepuscular hunters but may also be active during the day. Therefore their vision must be sensitive enough to function at night, but also by day. They achieve this by having a high number of rods in their retinas. These are sensory cells adapted to detecting low light intensities. Conversely we have a high number of cones in our retinas giving us great daylight vision but poor night vision.
Cats do however have a cone-rich patch at the centre of the retina for detecting day light levels. Their pupils are able to expand considerably at night allowing light to the rods, and then contract into elliptical slits during the day restricting light to the cones. They also have a further adaptation for improved night vision which is a reflective layer behind the retina called a tapetum lucidum. This layer reflects light back on to the retina, maximising its stimulation and providing a brighter image. Finally, big cats possess excellent stereoscopic vision for judging distances in order to pounce successfully on prey with paws and jaws. Interestingly only we humans and a handful of other primate species have superior vision in this department.
Big cats also have clever adaptations in their inner ear structure which enables them to hear a wide frequency range. Lions are particularly specialised in hearing low frequency sounds at great distances. This is important for communicating using roars and hearing the sounds of hooves of distant herds of prey.
The sense of touch provided by whiskers in big cats is hugely important to their lifestyles and hunting abilities. Whiskers sit in fluid-filled sacks which have a rich nerve supply so if anything touches the whiskers it is detected instantly. The whiskers on the cheeks and above the eyes of big cats are probably most important for protecting the eyes. The whiskers on the muzzle however are positioned for one main purpose only—to guide and orientate the killing bite. When pouncing on prey big cats extend their muzzle whiskers outward and forward like a net to feel for the neck of the prey to accurately deliver the knockout blow.
The skeletons of big cats vary between species depending on their lifestyles, habitat and hunting techniques. Limb length is a compromise between long length for speed as in the cheetah and short length for a powerful grasp as in the jaguar. The bones in their limbs are tightly bound by ligaments and tendons, reducing dexterity but improving strength and stamina. Unlike other predatory mammal groups they have a flexible elbow joint enabling inward rotation of their paws and claws to grapple and manipulate prey. The clouded leopard is able to rotate its rear ankles by 180 degrees to descend trees head first or even hang on to a branch with a single hind poor.
One skeletal adaptation all big cats have in common however is a highly flexible and extendable spine. For example, in a hunting cheetah the spine bends to maximise stride length, in a snow leopard the spine twists as the cat swiftly descends a rocky cliff face, or in a lion where the spine can flex to provide the agility required to take down large agile prey. The tail of big cats is designed to assist with balance either while climbing, leaping or turning sharply at high speeds. Uncontrollable twitching of the tip of the tail has been observed in a number of big cat species as they stalk prey. This might seem like it would give the game away but it has been suggested this behaviour may distract or even attract prey, helping to make the hunt more successful.
At the business end of a big cat you will find the paws and claws. Soft paw pads ensure a silent, firm grip during a hunt and they are placed in such a way as to avoid any vibrations caused by the elastic properties of the paw pads. Cheetahs have evolved hard ridges on their paw pads to aid traction during a hunt and the snow leopard has enlarged paw pads to increase the surface area of the paw and reduce the chance of sinking in snow.
All cats are renowned for their retractable and extremely sharp claws which remain housed in a fleshy sheath when not in use so they do not become blunted by contact with the ground. Big cats are no different and will regularly use trees as scratching posts to maintain their sharp claws. When a big cat pounces it will rapidly protract its claws like switchblades to grasp the prey. A single non-retractable claw called a dew claw is positioned like a thumb and is crucial for grasping prey, especially in the cheetah which has the largest dew claw of all big cats. The hind claws are generally less curved and pointed, but flatter and more blade-like, and are often used for lacerating and disembowelling captured prey when raked by the hind feet.
The paws and claws of big cats are supremely adapted for the task of taking down the perfect prey but they are nothing without the jaw to deliver the killing bite. Cats have a relatively short muzzle and jaw compared to other predatory mammals but this does not put them at a disadvantage. In fact there are a number of advantages to this adaptation. Firstly, a short muzzle means a wider bite (distance between the canines) which delivers a more dangerous killing bite meaning larger prey can be targeted.
Secondly, this greater distance between the canines enables efficient use of incisors for stripping flesh from bone. Finally, a shorter muzzle and jaw increases the mechanical efficiency (decreases the moment arm of resistance) of the jaw muscles resulting in a more powerful bite. The killing bite is delivered in one of two ways depending on prey size. The back of the neck is usually targeted on small prey whereas a bite to the throat or snout is delivered on larger prey. Both throat and snout bites require the maximum bite force to compress the respiratory system of the prey for suffocation. The canines are equipped with large nerve fibres that are thought to allow big cats to feel their way through a bite.
Love lions? Can’t get enough of cheetahs? Why not check out our amazing big cat documentaries, now available on the Love Nature App.
Reference: Kitchener, Andrew C., Blaire Van Valkenburgh, and Nobuyuki Yamaguchi. (2010). “Felid form and function.” Biology and conservation of wild felids. Oxford University Press, Oxford. 83-106.