Which animal has the most teeth?
On average, humans have around 28 teeth – 14 in each jaw. There is of course variation around this, as some people are born with genetically fewer teeth than normal (a condition called ‘hypodontia’) and some people are born with extra additional teeth (referred to as ‘supernumerary’ teeth). About 6% of people have some hypodontia, usually with only one or two teeth missing and about 3% of people have extra ‘supernumerary’ teeth. Even with all these variations, humans don’t even remotely come close to having the most teeth in the animal kingdom.
Teeth in the animal kingdom are widely varied from our human teeth – a Narwhal tusk is actually just an elongated canine tooth that has burst through their top lip! Hippo teeth grow continuously throughout their lives and sharks have teeth that renew themselves. If you were to think of which animal had the most teeth in the animal kingdom, a good bet would be a shark. They have 3000 teeth at any one time, arranged in rows. If one tooth falls out, then a tooth from the row behind comes forward to replace it. This means that some requiem sharks can go through 30,000 teeth in their lifetime. Despite this, sharks are not the most toothy-grinned of all animals. Instead, there is another, smaller, more local animal that can have up to 25,000 teeth in its mouth at any one time.
It is (of course), the humble garden snail! Snails have weird and wonderful teeth; they are tiny microscopic hooks that latch onto food and drag it into the mouth. Much like a shark, snail teeth are arranged in rows, ready to replace those which have fallen out at the front. This biological set up in snails and slugs is called a ‘radula’ and it most closely resembles a tongue covered with rows of spikes.
Radula teeth aren’t made like human teeth, hence their tiny size. Human teeth (and most other teeth in the animal kingdom) are made from calcium phosphate, but ranula teeth are instead made of a material called ‘chitin’. Chitin is essentially fibre and it actually makes up the exoskeleton of insects, so not only do snails have the most teeth, they have teeth that aren’t technically teeth at all – they’re made of insect skeleton.
Snails belong to a class of animal called gastropoda, which also includes slugs and limpets. There is internal competition within the gastropoda family for which specific species has the most teeth – all of them possess a ranula-style arrangement of teeth so competition is strong. The winner has a whopping 750,000 teeth in its lifetime and is a species called Umbraculum Umbraculum, or the ‘umbrella slug’. The umbrella slug is a colourful, tropical ocean dwelling slug that feeds on sponges, a task it presumably finds very easy, given its many teeth.
So, the next time you’re in your garden or the park and spot the humble snail, be sure to give it some respect, they have a nasty bite!