Historical Geology Understanding Our Planet\'s Past

crocodiles, and primitive mammals. The dinosaurs included herbivorous hadrosaurs and triceratops along with the carnosaurs that ...

Figure 169The paleogeography of the Cretaceous period, showing a major inland sea Figure 170Cretaceous Mancos shale and Mesa Ver ...

Apparently during the middle Cretaceous, Australia, while still attached to Antarctica, wandered near the Antarctic Circle and a ...

Moreover, those species already in decline, including the dinosaurs and pterosaurs, might have been dealt a final death blow fro ...

The impact sent 500 billion tons of debris into the atmosphere. Glow- ing hot bits of crater debris flying past and back through ...

plankton disappeared along with most marine life in the upper portions of the ocean. Sixty-five-million-year-old sediments found ...

T his chapter examines the evolution of the mammals and the chang- ing landscapes during the Tertiary period. The Cenozoic era, ...

THE MAMMALIAN ERA The first mammals were tiny, shrewlike creatures that appeared in the late Trias- sic about 220 million years ...

mals into new environments. During this time, rodents, the largest group of mammals, appeared in the fossil record. During the r ...

Free ebooks ==> http://www.Ebook777.com only half had lived in the proceeding Cretaceous while almost two-thirds are still li ...

the extreme environmental swings over the last 3 million years, when glaciers spanned much of the Northern Hemisphere. The numbe ...

also have a coat of insulation, comprising an outer layer of fat and fur to prevent the escape of body heat during cold weather. ...

Figure 176Diprotodon was the world’s largest marsupial. Figure 177Tertiary plants of the Chickaloon Formation, Cook Inlet region ...

appear to have evolved by about 25 million years ago. Grasses were the most important angiosperms, providing food for ungulates ...

Whales presented a mystery as vast as the animals themselves.The ances- tor of modern whales appears to have been a four-legged ...

Ridge is an undersea volcanic mountain range that runs 3,000 miles south from the Bay of Bengal,India.It formed when the Indian ...

the ocean floor more than 90 million years ago, when a series of volcanic eruptions released immense quantities of basalt onto t ...

an area of about 200,000 square miles, in places reaching 10,000 feet thick. Periodically, volcanic eruptions spewed out batches ...

by following volcanic rocks for 400 miles across Idaho’s Snake River Plain. During the last 2 million years, it was responsible ...

Free ebooks ==> http://www.Ebook777.com Arizona north into Utah and east into Colorado and New Mexico. Initially, the area su ...