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Pachycephalosauria (Pachycephalosaurs) |
Translation: Dome-Headed Lizards
Pachycephalosauria (pak-ee-sef-uh-lo-SAW-ree-ah) is an infraorder of the
Marginocephalia branch of ornithischias. Members are marked by very thick
skulls with various bony ornamentations. (In Pachycephalosaurus, its dome-shaped
head was composed of bone up to ten inches thick.) The domes may have been
used for ramming their attackers, but it is just as likely that they were
used in the same way modern deer and antelope use their horns -- in mating
rituals or to settle territorial disputes. Bipedal, they had small, short
teeth, grew up to 15 feet (4.6 meters) long, and lived during Late Cretaceous.
Translation: Dome-Headed Lizards
Pachycephalosauridae (pak-ee-sef-uh-lo-SAW-ree-day) is a family of the
ornithischian infraorder Pachcephalosauria. The small to medium-sized members
are marked by helmet-like, dome-shaped heads. Bipedal, they had short sharp
teeth, grew up to 8 feet (2.4 meters) long, and lived during Late Cretaceous.
A paleontologist (pay-lee-on-TOL-o-jist) is a scientist who studies ancient
life through the fossil record. According to Michael Brett-Surman, of the
Smithsonian Institution, "Being a paleontologist is like being a coroner,
except all the witnesses are dead, and all the evidence has been left out
in the rain for at least 65 million years."
Paleontology (pay-lee-on-TOL-o-jee) is the study of ancient life through
the fossil record.
Translation: Ancient Life
Paleozoic (pay-lee-o-ZO-ik) is the era before the Mesozoic Era. This era
began 600 million years ago and ended 245 million years ago. During the
Paleozoic, fish and sea plants developed.
During the Permian and Triassic Periods, Pangea (pan-GEE-uh) was a supercontinent
that accounted for most of Earth's land mass. During Late Triassic Period,
Pangea split into Laurasia and Gondwanaland.The term "Pangaea"
(All Earth) is derived from the Greek "pan" meaning all and "gaia"
Unlike many modern reptiles, dinosaurs appear to have cared for their young.
A trackway in Texas seems to indicate that sauropods surrounded their young
when traveling. Nests of Maiasaurs found in Montana provide evidence that
their young were cared for until they were fairly large: fossil skeletons
of young dinosaurs found in nests show worn teeth, which suggests that
they were fed by adults after they had hatched and while they were still
living in the nest.
The Permian (PUR-mee-en) Period is
the final period in the Paleozoic Era, beginning 290 million years ago
and ending 245 million years ago. The next period is the Triassic Period
in the Mesozoic Era.
Translation: Flat Lizards
Plateosauridae (play-tee-uh-SAWR-ih-day) is a family of prosauropods marked
by short hands and fingers that spread outward. The plateosaurids were
bipedal herbivores. They lived during the Late Triassic Period. The largest
plateosaurid was recorded to be 27 feet (8.2 meters) long. Lufengosaurus
Translation: Swift-footed Lizards
Podokesauridae (po-doe-kee-SAWR-ih-day) is a family of ceratosaurs that
grew to 10 feet (3 meters) long and lived during Late Triassic to Early
Jurassic Periods. This family of dinosaurs is marked by comparatively short
necks, five-fingered hands and long, slender hind legs.
Translation: Before Elegant Jaws
Procompsognathidae (pro-komp-so-NAY-thih-day) is the most primitive of
the coelurosaur families. They were bipedal carnivores with long necks
and tails and four-fingered hands. Procompsognathids lived during the Late
Triassic Period. Lukousaurus and Procompsognathus
Translation: Before Sauropods
Prosauropoda (pro-saw-uh POH-dah) is one of two branches of Sauropodomorpha.
As the name indicates, prosauropods were primitive progenitors of sauropods.
Prosauropods were herbivorous, bipedal, semi-bipedal, or quadrupedal dinosaurs,
with thick, five-toed hind limbs and five-fingered forefeet. Prosauropods
bore a large thumb-claw on their first toe. Their size ranged from small
to very large, and they bore small heads atop long necks.
Translation: First Horned Faces
Protoceratopsidae (pro-toe-sair-uh-TOPS-ih-day) is a family of Neoceratopsia.
Like later ceratopsians, members had parrot-like beaks and well-developed
frills, but small or non-existent horns. Quadrupedal herbivores, protoceratopsians
grew up to 7 feet (2.1 meters) long. This family of dinosaurs lived during
the Late Cretaceous Period. Microceratops, Montanoceratops,
Translation: Parrot Lizard
Psittacosauridae (sit-uh-ko-SAWR-ih-day) is a family of ceratopsians. Bipedal
plant eaters, they had large heads, and beaks for a snout. Psittacosaurids
grew up to 6 feet (1.8 meters) long and lived during the Cretaceous Period.