No Sweets For Sour Puss
By Hannah IsomThere may be a reason that 8 out of 10 cats prefer a certain brand of meaty chunks. When it comes to chowing down, our feline friends only have eyes (or more accurately, a tongue) for meat and are completely unable to taste anything sweet.
This revelation occurred when scientists discovered that cats lack the gene required to taste sweet food. Other mammals, such as humans, have the ability to taste a range of flavours grouped into sweet, salty, sour and bitter, as well as ‘unami’ (savouriness) and fat. Food entering the mouth is detected by taste buds (each of which contains about 100 taste receptor cells) which send a message to the brain telling us what the food tastes of. Cats, however, do not have the Tas1r2 gene that is required to make these receptors.
It is not known exactly why cats have more of a meat tooth than a sweet tooth, but as with most unexplained oddities in science, it is thought to have some kind of ‘evolutionary purpose’. In evolutionary terms, it makes sense to be able to taste things so the brain knows what food is good for us, and what could lead to a nasty case of the squits, or even death. Generally the things that the body needs – such as carbohydrate, fats and protein – taste nice, whereas nasty and potentially poisonous foods are less palatable. It is thought that humans particularly enjoy the taste of sweet food because sweetness is a sure sign of carbohydrates.
Evolutionary theory may be working against domestic cats, however. Modern cat food has a high carbohydrate content, which is thought to be behind the rise in cat diabetes. But because cats can’t taste the carbohydrate, they don’t know when they’ve eaten too much of a good thing (unlike humans, where eating too much of a good thing is all part of the fun).
We needn’t feel too sorry for our moggies though, as they are supertasters in their own right and can taste things that we humans can’t. In fact, cats can detect the molecule ATP (adenosine triphosphate), which supplies the energy for all living cells and is a ‘signal for meat’, according to Joe Brand from the Monell Chemical Senses Center in Philadelphia, who carried out the research.
And cats aren’t the only animals with odd tastes. Chickens also lack the sweet gene, and catfish can taste amino acids in the water around them. This helps the fish track down rotting flesh when they are feeling peckish. Lovely.
How about a little something to round that off with?
- Silly - Cat flight a possibility
- Scary - Death cat on the prowl
- Mad - Killer veggies
- Yum - Dinosaur bone soup
Image: Andrea Simonato