A more reliable way of estimating the size of megalodon shows the extinct shark may have been bigger than previously thought, measuring up to 65 feet, nearly the length of two school buses. Earlier studies had ball-parked ...
Paleontology & Fossils
Jun 7, 2021
0
4204
A case study led by Southern Illinois University, Illinois, has described the earliest discovery of an ovarian teratoma, a type of tumor that contains well-differentiated tissues developed from three germ cell layers (ectoderm, ...
Adolf Hitler definitely died in 1945 in Berlin, from taking cyanide and a bullet, according to French researchers who were given rare access to fragments of the dictator's teeth held in Moscow.
Archaeology
May 19, 2018
29
2343
Scientists have found an unexplained cache of fossilized shark teeth in an area where there should be none—in a 2900 year old site in the City of David in Jerusalem. This is at least 80 km from where these fossils would ...
Archaeology
Jul 4, 2021
2
1634
New research from the University of Central Florida has identified physiological features that could make people super-spreaders of viruses such as SARS-CoV-2.
Soft Matter
Nov 19, 2020
6
1323
The largest marine predator that ever lived was no cold-blooded killer. A new analysis by environmental scientists from UCLA, UC Merced and William Paterson University sheds light on the warm-blooded animal's ability to regulate ...
Paleontology & Fossils
Jun 26, 2023
0
1752
(Phys.org)—Using CAT scans and making 3-D virtual reconstructions of the jaws of the ancient fish Helicoprion, Idaho State University researchers have solved some of the mysteries surrounding large spiral fossils of this ...
Archaeology
Feb 27, 2013
1
2
(Phys.org) -- German researchers studying shark teeth have found at least two species that have fluorinated calcium phosphate - mineral fluoroapatite, as a main component, one of the main ingredients in toothpaste, which ...
Humans have the highest prenatal growth rate of all extant primates, but how this exceptional rate came about has been a mystery up to now. Leslea Hlusko, a scientist at the Centro Nacional de Investigación sobre la Evolución ...
Evolution
Nov 8, 2022
0
190
Why did birds lose their teeth? Was it so they would be lighter in the air? Or are pointy beaks better for worm-eating than the jagged jaws of dinosaur ancestors?
Evolution
May 23, 2018
14
723
Teeth (singular tooth) are small whitish structures found in the jaws (or mouths) of many vertebrates that are used to tear, scrape, and chew food. Some animals, particularly carnivores, also use teeth for hunting or defense. The roots of teeth are covered by gums. Teeth are not made of bone, but rather of tissues of varying density and hardness.
Teeth are among the most distinctive (and long-lasting) features of mammal species. Paleontologists use teeth to identify fossil species and determine their relationships. The shape of the animal's teeth are related to its diet. For example, plant matter is hard to digest, so herbivores have many molars for chewing. Carnivores, on the other hand, need canines to kill prey and to tear meat.
Mammals are diphyodont, meaning that they develop two sets of teeth. In humans, the first set (the "baby," "milk," "primary" or "deciduous" set) normally starts to appear at about six months of age, although some babies are born with one or more visible teeth, known as neonatal teeth. Normal tooth eruption at about six months is known as teething and can be painful.
Some animals develop only one set of teeth (monophyodont) while others develop many sets (polyphyodont). Sharks, for example, grow a new set of teeth every two weeks to replace worn teeth. Rodent incisors grow and wear away continually through gnawing, maintaining relatively constant length. Many rodents such as voles (but not mice) and guinea pigs, as well as rabbits, have continuously growing molars in addition to incisors.
This text uses material from Wikipedia, licensed under CC BY-SA
