Lesson 3: Eating Flashcards
Herbivores tend to have …?
Thin, ridged or “leafshaped” teeth for shearing and broad, flat teeth for grinding. Modern birds lack teeth, but herbivorous birds tend to have short, triangular beaks. Herbivores that browse high in trees, but cannot climb, have long legs and necks – like giraffes.
Carnivores tend to have …?
Sharp pointed teeth for piercing, and sharp hooked claws for holding onto struggling prey. Raptorial birds have sharp and hooked beaks and claws. Like modern carnivores, carnivorous dinosaurs usually have sharp teeth and hooked claws, and, like some carnivorous lizards, most also have teeth with serrated edges.
What are serrations?
Serrations are small sharp bumps on a tooth that are arranged in a line that usually runs from the tip to the base of the tooth. Serrated tooth edges helped carnivorous dinosaur teeth to slice through flesh.
What is a frugivore? Give a modern example.
Frugivores eat primarily fruit. The beak of a parrot is sharp and hooked (not unlike the beak of a carnivorous bird), because it needs to rip and tear apart the peels and protective husks of large tropical fruits.
What is a piscivore?
Piscivores are specialized carnivores that primarily eat fish. Piscivores tend to have tall, sharp, conical teeth that usually lack serrations. These adaptations make piscivore teeth good at spearing and holding onto slippery fish. Piscivores also tend to have long jaws that are capable of snapping shut quickly. Piscivorous birds tend to have spear-shaped beaks that are long, strait, and sharp at the tips. The Common Loon and piscivorous crocodilian, the gharial (Gavialis gangeticus) are examples.
What is an insectivore?
Insectivores are specialized carnivores that primarily eat insects. Some insectivores, like shrews and hedgehogs, have sharp piercing teeth for puncturing the chitinous exoskeletons of insects. But many insects are soft bodied and can be swallowed whole, without being chewed, so many insectivores have weak jaws and reduced teeth. Some insectivores, such as anteaters, pangolins, and echidnas, have no teeth at all. Because many insectivores must find their prey by digging, insectivores also commonly have large spade-shaped claws and powerful, but short, limbs. Another example of a digging insectivore is the echidna (Tachyglossus aculeatus).
What is durophagy?
Some carnivores, like hyenas, Tasmanian devils, and alligators, have sharp teeth for puncturing and ripping flesh but also have strong rounded teeth that enable them to crack bones – this is termed durophagy. Durophagy also requires extremely powerful jaws.
What are omnivores?
Omnivores are animals that eat significant amounts of both meat and plants. Humans are a good example of an omnivore, as are pigs, most bears, rats, crows, and many turtles. Omnivores tend to have either unspecialized beaks and teeth or a variety of teeth with different shapes (some shaped like those of herbivores and others like those of carnivores).
What is resorption?
Resorption is the chemical process by which a dinosaur breaks down its own teeth and bones so that the minerals and nutrients that compose them can be reused. After a new tooth was ready to replace an old one, and after the old tooth’s root was reabsorbed, the top, or “crown”, of the old tooth could be shed.
Tyrannosaurus rex replaced each tooth once every …?
1.5 to 2 years.
Can shed theropod teeth present around another dino’s skeleton tell us whether the theropod killed the other dino?
No. The presence of shed theropod teeth around another dinosaur’s skeleton cannot tell us whether or not the theropod actively hunted and killed the other dinosaur, or if it was only scavenging on an already-dead dinosaur.
How did dinosaurs digest plant material (specifically cellulose)?
The walls of plant cells are made of a compound called cellulose. Cellulose is tough stuff, and it makes plants a difficult source of food. Animals cannot digest cellulose on their own. Animals need help from bacteria that live within their stomach and intestines. Even with the help of bacteria, getting all the raw energy that a large animal needs to survive from plants is not easy. Chewing food before sending it down to the digestive organs helps, because chewing breaks plants into smaller pieces that are easier for bacteria and digestive enzymes to envelope.
What are dental batteries?
The dental batteries of some herbivorous dinosaur groups are one way of dealing with the challenge of cellulose. Dental batteries are arrangements of densely packed teeth that collectively form a single, large chewing surface, and two groups of dinosaurs evolved dental batteries: hadrosaurs and ceratopsians. Because the individual teeth that make up dental batteries are small, and because chewing grinds teeth down quickly, dinosaurs with dental batteries replaced their teeth rapidly.
In the skull of a hadrosaur, there can be over ___ teeth.
1,000. Most of these teeth were not actively contributing to the chewing surface. Instead, they are replacements that were already fully formed and waiting in line.
The chewing surfaces of dental batteries are complex. Dinosaur teeth are made of a variety of hard tissues, including ___ (which usually covers the outside of a tooth) and ___ (which is usually common on the inside of a tooth). As a tooth in a dental battery was ground down, different tooth tissues were exposed, and these different tissues would be ground down at a slightly different rate, making the chewing surface slightly uneven. The chewing surface of a dental battery is not simple, uniform, or smooth. It is intricate, varied, and abrasive.
Enamel and dentine.
