People who lose the use of one or more of their senses – particularly sight – will almost always find that to compensate, their other senses become heightened.
Blind people invariably have far more acute senses of smell and hearing, and their sense of touch – almost redundant in many people – becomes an indispensable tool. Just think of Braille; entire books can be read, purely through touch!
I was thinking of this the other day when on leave in Cape Town. I don’t know if any of you have visited the Kirstenbosch National Botanical gardens below Table Mountain, but there is a walk that one can do with a purely aromatic focus called the Fragrance Garden. Heavily scented and textured plants line each side of the walkway, and a description of each species accompanies it in Braille. One doesn’t have to rely solely on sight to experience the magic of the botanical world, and every visitor is encouraged to immerse themselves in the walk purely by using the hand rail and their senses of touch and smell.
Walking through the Fragrance Garden and seeing the Braille plaques, I started thinking about the sense of touch, and in particular those of the big cats, with my main thoughts being about whiskers.
Now I know we’ve had quite a leopard-centric few days, but seeing as how these big cats are the main attraction at Londolozi more often than not, and their whiskers are the most impressive of any species here by a long shot, let’s discuss.
An understanding of the basic functioning of whiskers is necessary before we proceed.
Firstly, we need to be familiar with the term vibrissae, which is the more biologically correct term for whiskers. Simply put, they are modified hairs that have become specialized touch organs. Whiskers are a type of vibrissae that grow around the nose, mouth and eyes, but hairs all over certain mammals’ bodies can be classed as vibrissae.
As these hairs brush against something, be it a blade of grass or something less delicate, the vibrissae are moved accordingly, depending on the hardness and texture of the object.
Nerve cells are embedded into the hair follicle at the base of each vibrissa (singular of vibrissae), and any motion of the hair will trigger these sensors.
Seals, that often fish in water where the visibility is effectively zero, have extremely sensitive whiskers, with up to 1500 motion sensors per whisker. Rats and cats – that can rely far more on other senses to help them find food – have 100-200. In fact, the term “whisker” comes from the back and forth whisking motion that seals and other mammals use to locate prey.
The way in which the vibrissae at stimulated will be translated by the motions sensors and the nervous system into information about the direction, velocity and duration of the stimulation, allowing the animal to form an accurate picture of what it came into contact with.
Now that we understand how vibrissae work, let’s look at them in the context of a leopard.
Essentially a leopard’s entire body is covered with vibrissae. Thousands of hairs are constantly feeding the leopard information about the terrain it’s moving through, but the whiskers around the face are by far the most important. If one examines a leopard’s whiskers closely, especially when compared with a lion, they almost start to look disproportionate to its body size.
Lions, being pride hunters, don’t need to be as acutely aware of every little permutation of the grass they are stalking their prey through. Should anything go wrong, and they inadvertently make more noise than intended due to some rough foliage brushing against them, they will more than likely have some pride mates backing them up.
A leopard however, has no such luxury. It hunts successfully or it slowly starves.
Every. Single. Step. That it takes. Might be the difference between a successful hunt and hunger. Evolution has recognized the need for some extra help, and this is where the whiskers come in. From tip to tip a leopards’ whiskers are going to be about as wide as it’s body.
That’s pretty significant. It means that the leopard, a solitary hunter, can lock its focus on its prey without once deviating, and while it is stalking it will be getting fed constant information about what it is stalking through; whether the grass might rustle. Whether the gap between those branches is big enough to squeeze through without making a noise. Low visibility conditions such as the dead of night will also let the whiskers come into their own; a continuous feedback system keeps the leopard totally in tune with what it is moving through and how the hunt might be impacted. The gaff would be blown far more often during a leopard’s hunt if it didn’t have such incredible whiskers, that I can guarantee.
As beautiful as leopards are, it’s only by having an understanding of the subtle intricacies of their anatomy that we can truly appreciate how they are one of nature’s ultimate synergies.