Columbia Encyclopedia

(Encyclopedia) Pachycephalosaurus păkˌĭsĕfˌəlōsôrˈəs [key] [Gr., = thick-headed lizard], bipedal herbivorous dinosaur of the late Cretaceous period, approximately 68–65 million years ago. Its disting...

(Encyclopedia) Ankylosaurus ănˌkələsôrˈəs [key], [Gr.,=crooked lizard], genus of heavily armored, herbivorous quadripedal dinosaurs, the best known of which is the species A. magniventris, the largest and hea...

(Encyclopedia) Wollemi pine wŏlˈəmīˌ [key], primitive tree, Wollemia nobilis, of the conifer family Araucariaceae, named after Wollemi National Park in New South Wales, Australia, where it was discovered in 199...

(Encyclopedia) Plesiosaurus plēˌsēəsôrˈəs [key], genus of extinct predatory marine reptiles that arose in the Triassic period of geologic time and continued into the Jurassic and Cretaceous periods. Plesiosau...

(Encyclopedia) Agassiz, Alexander ăgˈəsē [key], 1835–1910, American naturalist and industrialist, b. Neuchâtel, Switzerland; son of Louis Agassiz, stepson of Elizabeth Cary Agassiz. He came to the United Stat...

(Encyclopedia) Deccan dĕˈkänˌ [key], region of India. Sometimes defined as all India S of the Narmada River, it is in a more limited sense the plateau of central peninsular India, including approximately all Kar...

(Encyclopedia) Tyrannosaurus tīrănˌōsôrˈəs, tĭr– [key] [Gr.,=tyrant lizard], member of a family, Tyrannosauridae, of bipedal carnivorous saurischian dinosaurs characterized by having strong hind limbs, a m...

(Encyclopedia) Apatosaurus ăpˌətəsôrˈəs, āˌpătˌə– [key], [Gr.,=deceptive lizard], quadruped saurischian dinosaur, estimated to be from 70 to 90 ft (21 to 27 m) in length and to weigh up to 30 tons (27 ...

(Encyclopedia) Geologic Timescale 1 Not an era but the time preceding the Cambrian. ...

(Encyclopedia) Mesozoic era mĕzˌəzōˈĭk [key] [Gr.,=middle life], major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 65 to 225 million years ago. Great crustal disturb...