Setting off on our evening’s game drive, we had crossed the river to explore the Northern part of our reserve. Not long after, I had received an update that there was an elephant carcass with vultures scattered around the site. It seemed as though the elephant had been there for some time. Little did we know that this game drive would result in the question: can predators taste?
We awaited the next update: two male lions had come onto the scene and had begun feeding on the carcass. Of course, we had to go and see this for ourselves.
Long before we even saw the lions, the smell of the elephant had caught our attention, giving us zero doubts about the direction we needed to head towards. There was no need to be close to the site to know that there was a carcass close by.
One of my guests quickly spotted the lions feeding, but as we got closer, the odour got so strong that he exclaimed “How are those lions eating the meat? With a smell like that, imagine how disgusting it must taste!”
Although the lions looked content in their meal, it did raise an interesting question: can predators taste what they’re eating? And do they care what it tastes like?
The Biology of Taste
Most mammals’ tongues have taste receptors — proteins that bind to the substances we’re putting in our mouths. These interactions stimulate signals that travel through nerve cells to the brain and provide us with the sensation of taste. Humans have five primary taste receptors — Sweet, Salty, Sour, Bitter, and Umami (Savoury).
However, not all animals have a taste spectrum as wide as humans. New studies suggest that certain unneeded taste receptors may be lost in certain species through evolution.
The Evolution of Taste for Survival
Different species have different reasons for prioritising some tastes over others, and it all comes down to evolution and survival; which foods will offer the most beneficial and nutritious meal? Taste is a complex matter and is shaped by evolution and the environment.
Carnivores (animals who eat only meat as part of their diet) generally have fewer taste receptors than omnivores. Lions, for example, have about 470 taste receptors on their tongues. On the other hand, humans who eat fruits, vegetables, and grains in addition to meat, have an average of 10,000 taste receptors. This means that we are able to pick up a stronger sense of taste than these animals.
Cats carry damaged versions of the genes that build sugar detectors on the tongue, and cannot, therefore, taste sweet. As cats are carnivores, sweet receptors aren’t necessary for their survival. On the other hand, they have a great number of receptors that allow them to detect bitter flavours, helping them to avoid overly rancid meat.
So far, cats are the only mammals lacking the sweet gene; even close relatives among the carnivores, like mongooses and hyenas, have it.
Dogs, which are mostly carnivorous, have about 1,700 taste buds. Canines perceive many of the same tastes as humans, however, they experience them on a reduced scale. This explains why our domestic pet dogs are happy putting just about anything in their mouths – with fewer taste receptors, the intensity of flavour is a lot lower.
This makes sense in evolutionary terms too, as competition might prevent the animal from having time to savour anything for too long. Dogs often gulp their food up quickly before another can steal it, and whoever finishes first is the winner, in the sense of retaining their meal.
All carnivores also have special taste buds that are modified for water. These receptors are placed at the tip of the tongue, the part that encounters water while drinking. This part of the tongue always responds to water; however, it becomes more sensitive when the animal eats something salty. This increases the need for water and is useful for animals that consume a lot of meat (which has a high salt content).
Back to the original question:
Can predators taste what they’re eating? And do they care what it tastes like?
Predators can taste what they’re eating, but to a much less extent than what we, as humans, experience. In truth, taste isn’t much of an issue for carnivores. Animals of all classifications are after calories, not a flavour experience. The only reason they have a sense of taste is to determine which substances are dangerous. Even if predators had thousands more taste buds than us, they still wouldn’t be able to taste the presence of certain flavours because they simply don’t need that ability for survival.
A Final Note on Senses
I find it incredibly fascinating how evolution is quick to abandon capabilities that organisms no longer need. A while ago I wrote a blog on how birds’ vision differs from our own. Learning about different animals’ senses and the sensory evolution of various species has reminded me of just how different all animals experience the world. It’s hard for us to really imagine how other animals experience their realities as they can see wavelengths of light or hear frequencies of sound that we cannot.
We, in turn, can taste things that many predators can’t detect. What we sense is only a small portion of all there is to sense. And that portion has been developed through evolution to best meet the demands of our lifestyle.