Page 78 - (DK) The Ultimate Visual Dictionary 2nd Ed.

PREHISTORIC EAR TH

Quaternary period QUATERNARY POSITIONS OF
PRESENT-DAY LANDMASSES

THE QUATERNARY PERIOD (1.6 million years ago–present) forms the North Europe Asia
second part of the Cenozoic era (65 million years ago–present): it has America
been characterized by alternating cold (glacial) and warm (interglacial)
periods. During cold periods, ice sheets and glaciers have formed
repeatedly on northern and southern continents. The cold
environments in North America and Eurasia, and to a lesser
extent in southern South America and parts of Australia, have
caused the migration of many life-forms toward the Equator.
Only the specialized ice age mammals such as Mammuthus
and Coelodonta, with their thick wool and fat insulation,
were suited to life in very cold climates. Humans developed
throughout the Pleistocene period (1.6 million–10,000 years
ago) in Africa and migrated northward into Europe and Asia.
Modern humans, Homo sapiens, lived on the cold European
South
continent 30,000 years ago and hunted other mammals. The America Africa Australia
end of the last ice age and the climatic changes that occurred India
about 10,000 years ago brought extinction to many Pleistocene
Antarctica
mammals, but enabled humans to flourish.

EXAMPLES OF QUATERNARY PLANT GROUPS

A PRESENT-DAY BIRCH A PRESENT-DAY SWEEETGUM FOSSIL LEAF OF A SWEETGUM FOSSIL LEAF OF A BIRCH
(Betula lenta) (Liquidambar styraciflua) (Liquidambar europeanum) (Betula sp.)

EXAMPLES OF QUATERNARY ANIMAL GROUPS

PROCOPTODON DIPROTODON TOXODON MAMMUTHUS
Group: Macropodidae Group: Diprotodontidae Group: Toxodontidae Group: Elephantidae
Length: 10 ft (3 m) Length: 10 ft (3 m) Length: 10 ft (3 m) Length: 10 ft (3 m)

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