While humans just get baby teeth and adult teeth, sharks are constantly growing chompers throughout their entire life. A set of new teeth is always developing in the predators' jaw, and they rotate forward like a conveyer belt.
A polyphyodont is any animal whose teeth are continually replaced. In contrast, diphyodonts are characterized by having only two successive sets of teeth. Polyphyodonts include most toothed fishes, many reptiles such as crocodiles and geckos, and most other vertebrates, mammals being the main exception.
Rabbits, squirrels, and rodents have teeth that never stop growing. They have to chew on tough foods like nuts, leaves, and bark to wear down their teeth and keep them from growing too long.
Rodents' teeth grow all their lives. Reptiles' and sharks' teeth are replaced constantly, before they wear out. A crocodile replaces its teeth over forty times in a lifetime.
Mammalian Exceptions
Rodents and rabbits are another unique case. Their incisors grow continuously so they require regular gnawing to keep their teeth at a healthy length.
All rodents have a pair of upper and a pair of lower teeth called incisors. Unlike our teeth, these incisors don't have roots, and they never stop growing! To keep these teeth from growing into their brains, rodents grind their teeth against each other.
Alligators have between 74 and 80 teeth in their mouth at a time. As they wear down, they are replaced. An alligator can go through 3,000 teeth in a lifetime. Male alligators are larger than female alligators.
Snails: Even though their mouths are no larger than the head of a pin, they can have over 25,000 teeth over a lifetime – which are located on the tongue and continually lost and replaced like a shark!
Their teeth practically never stop growing because they are herbivorous and their teeth are designed for chewing grass and forage. In general they spend between 8 to 12 hours masticating while grazing, so their teeth get very worn down.
The number of teeth a shark grows and uses during its lifetime can be enormous – more than 30,000 teeth in their lifetime! That's roughly 937 times the number of teeth the average human has!
Hippopotamus – Hippopotamuses have the largest teeth of any land animal. Their canine teeth can grow to be 1.5 feet long and their front incisors grow to be around 1.2 feet long! Saltwater Crocodiles – Lastly, of all the animals in the world, the saltwater crocodile has the strongest bite force.
Lobsters and crabs have teeth— in their stomachs. These are used to crush its food, but they also have a strange secondary function in ghost crabs: making a noise that wards off predators.
The animal with the strongest bite in the world is the Nile crocodile. These scaly predators can snap their jaws with a whopping 5000 pounds per square inch of pressure. For comparison, we only use at most 200 psi to chew steak!
Poachers kill about 20,000 elephants every single year for their tusks, which are then traded illegally in the international market to eventually end up as ivory trinkets.
Several groups of mammals have decided to do without teeth altogether. The 10 species of Whales in the order Mysticeti, the 8 species of Pangolins family Manidae, and the 3 species of Anteaters in the family Myrmecophagidae and order Edentata have all given up on teeth completely and have none.
1) ORCA - Orcinus Orca. The Orca or Killer Whale is the largest member of the dolphin species family and has the sharpest teeth of all animals. Orcas are predators; they are at the top of the food chain in marine life. No other animal preys on orcas; they can even hunt seals, sharks, and dolphins.
COLUMBIA, Mo. – Unlike people, crocodiles do not clean their teeth to slow down wear and tear. Instead, they get rid of them and replace them with new copies.
The pattern found instead in most mammals (and believed to be primitive for the group) is diphyodonty, a term derived from Greek words meaning "twofold production of teeth." Most mammals are born with a special set of usually smaller, weaker teeth called milk teeth or deciduous teeth.
Because cows, sheep, and goats are constantly grazing and chewing, their teeth naturally wear down. This is important because ruminants' teeth never stop growing! This makes sense; unlike us, they graze all day long. Their constantly growing teeth and grazing habits work together to give them a healthy mouth and diet.
Based on the discovery of a single tooth, researchers say they have identified an ancient species of giant platypus. The finding provides new clues about the lineage of the modern platypus.
Leech: Leech is an annelid. Leech's external and internal segmentation do not correspond to each other. If the internal body is examined, it can be seen that the body is divided into 32 parts or segments which have their own corresponding brain.
The Babirusa is a hog with a dental problem, and has two very large canine teeth that can grow up to 8 inches long and even grow through their skin! The Babirusa's canine teeth never stop growing, and their top canines can grow and curl back onto themselves.
Deciduous teeth or primary teeth, also informally known as baby teeth, milk teeth, or temporary teeth, are the first set of teeth in the growth and development of humans and other diphyodonts, which include most mammals but not elephants, kangaroos, or manatees, which are polyphyodonts.
So then why do we need two sets of teeth for it? This is because our permanent set of 32 adult teeth are simply too big for a baby's jaw. That's why we have the initial baby teeth to ensure proper structure of our jaw, speech development, and easy chewing of food during our childhood.
Humans only get two sets of teeth in their lifetime: 20 primary (baby) teeth and 32 secondary (permanent) teeth. If you lose any of your secondary teeth, your teeth will not grow back a third time.