82
F
rom the beginning of
recorded history, people
have attempted to identify
organisms according to their uses.
Egyptian wall paintings from
c. 150 0 bce show, for example, that
people understood the medicinal
properties of many plants. In the
text History of Animals, written
in the 4th century bce, the Greek
philosopher and scholar Aristotle
made the first serious attempt to
classify organisms, studying their
anatomy, life cycles, and behavior.Features of classification
Aristotle divided living things into
plants and animals. He further
grouped about 500 species of
animals according to obvious
anatomical features, such as
whether they had blood, were
“warm-blooded” or “cold-blooded,”
whether they had four legs or more,
and whether they gave birth to live
offspring or laid eggs. He also noted
whether animals lived in the sea,
on land, or flew in the air. Most
significantly, Aristotle used names
for his groupings that were later
translated into the Latin words
“genus” and “species”—terms
that are still used by modern
taxonomists to this day.Aristotle placed animals in a scala
naturae (ladder of nature), with 11
grades distinguished by their mode
of birth. Those in the top grades
gave birth to live, hot, wet offspring;
those in the lower grades to cold,
dry eggs. Humans were at the very
top of the scale, with live-bearing
tetrapods (four-legged creatures),
cetaceans, birds, and egg-laying
tetrapods lower down. Aristotle
placed minerals on the bottom
grade of his scale, with plants,
worms, sponges, larva-bearing
insects, and hard-shelled animals
on the levels above.IN CONTEXT
KEY FIGURE
Aristotle (c. 384–322 bce)BEFORE
c. 1500 bce Different
properties of plants are
recognized by ancient
Egyptians.AFTER
8th–9th centuries ce Islamic
scholars of the Umayyad and
Abbasid dynasties translate
many of Aristotle’s works
into Arabic.1551–58 Conrad G essner’s
History of Animals classifies
the animals of the world into
five basic groups.1682 John Ray publishes his
History of Plants, which lists
more than 18,000 species.1735 Carl Linnaeus devises a
system of binomial names, the
first consistent classification of
organisms, according to which
he names every species listed
in his Systema Naturae.If any person thinks the
examination of the rest
of the animal kingdom
an unworthy task, he must
hold in like disesteem
the study of man.
AristotleIN ALL THINGS
OF NATURE THERE
IS SOMETHING
OF THE MARVELOUS
CLASSIFICATION OF LIVING THINGS
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