Page 95 - The Restless Earth Fossils

4 Fossils

Macroscopic An object that is visible without magnification.
Mass extinction events Periods of time during which a large
number of species disappear from the fossil record within a
relatively short time.
Mesozoic era Period of time from 251 to 65 million years ago
(The Age of Dinosaurs).
Meteorites Extraterrestrial objects that strike the Earth; large
ones are called asteroids.
Microfossils Microscopic fossils.
Microscopic An object that is visible only with magnification.
Mitochondrial dna DNA found in the mitochondria
of cells.
Mold Impression of a living thing in rock. (Casts are made
using molds.)
Molten Melted rock.
Morrison Formation Jurassic Age group of reddish rocks com-
mon in the American West.
Mudstone Mud turned to stone under heat and pressure.
Mummy Dried or freeze-dried remains of a once-living thing.
natural selection Selection by nature of only the most fit
organisms to reproduce.
neandertals Archaic, now-extinct humans who lived in
Europe and Asia during several periods of glaciation.
pachycephalosaurs Type of Cretaceous dinosaurs with bony
head shields.
paleobotanist Paleontologist who studies fossil plants.
paleontologist Scientist who studies fossils.
paleozoic era Period of time from 542 to 251 million years
ago.
periods Subdivisions of geological eras.
permineralization Crystallization of minerals out of solution
as water evaporates.
petrified Commonly used term to describe the mineralization
of wood.

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