I’ve often wondered just how certain animals can stomach certain things.
Taste buds play an important function in letting an animal know what is good or bad to eat. If you get right down to it, this can mean the difference between life or death; toxins or harmful substances will be detected by the buds, the body responds by deeming that food as not good to eat, and it will be avoided. Tasting accurately is therefore a matter of survival
At Londolozi, seeing a hyena gnawing away at week-old carrion, and more especially smelling that carrion yourself, can be enough to make your stomach turn. Yet out in the wilds, it can appear that – at least for the most part – the animals are rather indiscriminate in their taste selections. This is not the case however, and one needs to look at the animal’s lifestyle, diet and tongue structure in order to get a better appreciation of how things may taste to certain creatures, and why hyenas don’t gag when stuffing themselves on rotting hippo.
Carnivores are the obvious group to start with, as many of the things they eat might seem quite disgusting to us. When one examines their tongues, however, you find a marked difference between the density of their taste buds compared to ours. Humans have on average around 10 000 buds, whereas most carnivores have less than 500. That’s a ratio of 20:1.
Looking at exactly what the carnivores can and can’t taste, we find that they are receptive to bitter flavours, but can’t taste sweet things. This is because sugars aren’t part of their diet, so it is unnecessary for them to be able to detect them. Bitterness however, is important, as it can be the difference between truly rancid meat and meat that is still okay to eat. Obviously the definition of what constitutes rancid meat is slightly different for a male lion than it is for a human, but here we have to look at the carnivore’s digestive system as well. A digestive tract that is far more able to process meats and can handle bacteria that would give a person immediate and acute gastrointestinal problems has a far higher tolerance for meats that we would consider inedible.
The simple fact that carnivores’ diets consist of almost exclusively one type of food – meat – means that extra taste buds would simply be wasted. The herbivore’s need to detect toxins that would be in plants is not needed by carnivores, as unless they’re eating something like a Poison Arrow Frog, the meat they are consuming will be toxin-free.
Herbivores are at the other end of the spectrum, having far more taste buds than humans; more than double in some cases, with cows being in possession of around 25000. Although this seems contradictory, given that herbivores don’t eat a wide variety of food, and logic might dictate that they should therefore also have few buds, they actually need to be extremely sensitive about what they put in their mouths. Bulk grazers in particular who can munch away at whatever’s in front of them need to be able to distinguish the bitter tastes of dangerous plants that might be concealed amidst safe vegetation, as they might not be looking carefully at their food source. Sensitivity to toxins is crucial, as the plant world is full of chemical defences.
Sweet and salty do feature in the tastes of herbivores tastes as well, as plants containing different amounts of minerals need to be analysed and favoured depending on the animal’s immediate needs and electrolyte balance.
Catfish are the world champs of tasting, having about 175 000 buds; they often live in murky-water environments and sight will play almost no role in food detection. Ironically, despite having the most sensitive taste out there, catfish are some of the least tastiest of their family!
In the wild, where animals rarely have the luxury of the choice of food that many humans do, the preference for a certain item will almost always come second behind the necessity of eating when something’s actually available. If it’s in front of you and you can stomach it, eat it!
I guess I’m just grateful that tonight for dinner I’ll be able to opt for something that I like, as opposed to the hyena that I saw this morning, his head down to the ground, sniffing along and hoping to come across any kind of carrion he could find, be it fresh or over a week old. As to the question of whether carnivores are able to like something they’re eating, that’s a discussion for another day.
Interesting facts James. It is amazing how the animals (including us humans) all evolved differently.
I am very grateful to be a human! ? Very interesting article though, James! That explains a lot. Merry Christmas to you and the Londolozi group. Looking forward to more fine articles in the future.
Thanks Darlene, Merry Christmas to you too!
As always James, fascinating reading on the tastes of carnivores and herbivores. I have wondered about the safety of carrion after a couple of days as the smell alone is quite off-putting. I know that the felines tackle the innards first and then the meat, but who eats the skin? Hyenas, vultures, ?? It is interesting to note that there is something for everyone within the food chain as long as one has access. It’s easy for humans in the developed western countries as one can just go to a supermarket. In third world countries, I have seen the dependence on growing your own food or depending upon hunting – bartering works quite well here as well. I also believe that habitat plays a large part in the search and acceptance of food. For humans, how we are raised plays a great part in what we eat throughout life. Our digestive systems adapt to a certain level of sustenance and oftentimes, when traveling and that balance is altered, one can experience intestinal distress. In the animal world, it seems they are attuned to what works for them and if it’s not right, they walk away.
Thank you.
Thanks for the comments Denise. Exactly right. The animals still retain their finely tuned senses that tell them exactly what they should and shouldn’t be eating!
As for the skin of carcasses, yes it is mainly the hyenas and vultures that will consume it.
Best regards
Very interesting article! I’ve heard of lions in the Kruger eating a waterbuck carcass that was over a week old and elephant carcasses that were likely older (I guess in some instances they can’t afford to be picky). Though in the Mara they don’t like the taste of Defassa waterbuck there, due to the unpleasant taste of the meat (I’m guessing that’s the bitterness receptors at play).
As I am preparing a few dishes for Christmas dinner, I am certainly thankful to have the ability to choose what I put in the dishes. Merry Christmas, James. Hope all of your food is tasty.
Thanks for the comments Lucie,
I wholeheartedly agree!
Best regards and Happy Christmas.
One of the most fascinating blog posts that I have read. And as to your ‘…catfish are some of the least tastiest of their family…’ if Anna is reading my response, I hope she will create a TASTY catfish lunch or dinner for us when we are there in mid-February.
Thanks for the comments Jeff. Hmm I think you will have to put in a VERY special request to get catfish put on the menu! Haha
This is so interesting to know that we have a different amount of taste buds in comparison with animals. My word!