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GROUNDBREAKING
SCIENTIFIC EXPERIMENTS,
INVENTIONS, A N D
DISCOVERIES OF T H E
ANCIENT WORLD
Recent Titles in
Groundbreaking Scientific Experiments, Inventions and Discoveries through
the Ages
G r o u n d b r e a k i n g Scientific Experiments, Inventions a n d Discoveries of
the 17 th C e n t u r y
Michael Windelspecht
G r o u n d b r e a k i n g Scientific Experiments, Inventions a n d Discoveries of
the 18 th C e n t u r y
Jonathan Schectman
G r o u n d b r e a k i n g Scientific Experiments, Inventions a n d Discoveries of
the 19 th C e n t u r y
Michael Windelspecht
GROUNDBREAKING
SCIENTIFIC EXPERIMENTS,
INVENTIONS, AND
DISCOVERIES OF T H E
ANCIENT WORLD
R O B E R T E. K R E B S A N D C A R O L Y N A. K R E B S
Groundbreaking Scientific Experiments, Inventions
and Discoveries through the Ages
Robert E. Krebs, Series Adviser
GREENWOOD PRESS
Westport, Connecticut • L o n d o n
Library of Congress Cataloging-in-Publication Data
Krebs, Robert E., 1922Groundbreaking scientific experiments, inventions and discoveries
of the ancient world / Robert E. Krebs and Carolyn A. Krebs.
p. cm.—(Groundbreaking scientific experiments, inventions and
discoveries through the ages)
Includes bibliographical references and index.
ISBN 0-313-31342-3 (alk. paper)
1. Science, Ancient. 2. Technology-History. I. Krebs, Carolyn A. II.
Title. III. Series.
Q124.95.K74 2003
509.3—dc21
2003045530
British Library Cataloguing in Publication Data is available.
Copyright © 2003 by Robert E. Krebs
All rights reserved. No portion of this book may be
reproduced, by any process or technique, without the
express written consent of the publisher.
Library of Congress Catalog Card Number: 2003045530
ISBN: 0-313-31342-3
First published in 2003
Greenwood Press, 88 Post Road West, Westport, CT 06881
An imprint of Greenwood Publishing Group, Inc.
www.greenlwood.com
Printed in the United States of America
The paper used in this book complies with the
Permanent Paper Standard issued by the National
Information Standards Organization (Z39.48-1984).
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For Evan, Kira, and Heather, who are the future...
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CONTENTS
Illustrations
xi
Series Foreword
xiii
Introduction
xvii
1. Agriculture and Animal Domestication
Background and History (Agriculture)
Background and Breeding (Animal Domestication)
Principal Domesticated Species and Why They
Were Chosen
Development of Animal Equipment
Summary
16
24
30
2. Astronomy
Background and History
Astrology
The Geocentric View of the Universe
The Heliocentric View of the Universe
Compilation of Astronomical Maps and Star Catalogs
Discovery of Eclipses, Comets, Novas, and Sunspots
Calculating the Earth's Circumference
Calculating the Length of the Solar Year
Calculating the Earth's Ecliptic
Tides
Instrumentation
Summary
33
33
39
41
45
47
49
52
53
53
54
55
59
3.
61
61
Biology, Botany, and Zoology
Background and History
1
1
12
vill
Contents
The Greeks of Ionia
Athens—the Center of Ancient Learning
Taxonomy
Zoology and the Classification of Animals
Botany and the Classification of Plants
Reproduction
Summary
62
64
66
70
74
76
79
4. Communication
Background and Historv
Language
Writing and the Alphabet
Paper
Printing
Postal Systems
Summary
81
81
83
87
96
100
101
103
5. Engineering and Machinery
Background and History
Simple Machines
Building Materials and Construction
Water Systems
Summary
105
105
106
115
132
146
6 . Mathematics
Background and History
The Mathematics of Mesopotamia (Sumerian,
Akkadian, and Babylonian)
The Mathematics of Egypt
The Mathematics of China
The Mathematics of Ancient Greece
The Mathematics of the Indus Civilizations
Roman Numerals
Abacus
Pi (TT) or Squaring the Circle or "Perfect Exhaustion"
Zero
Summary
149
149
7 . Medicine and Health
Background and History
Primitive Medicine
History of Disease
179
179
180
182
152
155
159
162
169
171
173
174
176
178
Contents
Medicine
Medicine
Medicine
Medicine
Medicine
Medicine
Medicine
Medicine
Summary
8.
in Mesopotamia
in Palestine (Israel)
in Egypt
of the Indus Civilizations
in China
in Ancient Greece
in Alexandria (Egypt)
in the Roman Empire
Personal and Household
Background and History
Body Ornamentation
Contraception
Glass
Heating, Cooling, and Refrigeration
Ink
Lighting
Locks
Mirrors
Pottery
Sanitation
Weaving
9 . The Physical Sciences
Background and History
Fire and Its "Discovery" as a Tool
The Three-Age System
Metallurgy
Alchemy and Chemistry
Philosophy of the Physical Sciences
Summary
ix
183
185
186
190
192
197
202
203
209
211
211
212
217
219
220
222
223
225
227
228
234
237
243
243
245
246
248
253
258
264
1 0 .Timekeeping
Background and History
Absolute Time
Relative Time
Calendars
Timekeeping Devices
Summary
267
267
268
270
271
287
292
1 1. Tools and Weaponry
Background and History
295
295
x
Contents
Dating the Origin of Tools and Weapons
Survival Tools
Colonizing (Working) Tools
Weaponry
Summary
296
298
302
306
318
12. Transportation, Trade, and Navigation
Background and History
Transportation
Trade
Navigation and Exploration
History of Shipbuilding
Summary
321
321
322
325
330
335
347
Glossary
349
Selected Bibliography
357
Name Index
363
Subject Index
367
ILLUSTRATIONS
Figures
2.1 Aristotle's Geocentric Universe
36
2.2 Lunar, Solar, and Annular Eclipses
50
2.3 Chinese Sighting Tube
56
2.4 Ancient Plane Astrolabe
57
2.5 Armillary Astrolabon
59
3.1 Aristotle's Ladder of Nature
68
4.1 Evolution of the Modern Western Alphabet
(ca. 2000
B.C.E.
to present)
94
5.1 Six Simple Machines
107
5.2 Three Types of Levers
108
5.3 Three Types of Pulleys
111
5.4 Archimedes' Screw
114
5.5 Interior of the Great Pyramid of Khufu
121
5.6 Four Steps in the Construction of an Arch
126
5.7 Three Styles of Vaults
127
5.8 Crane, Pulley, and Lewis
131
5.9 The Shaduf
135
6.1 Babylonian and Arabic Numerals
153
6.2 Egyptian Hieroglyphics and Arabic Numerals
157
6.3 Egyptian Hieratic and Arabic Numerals
158
6.4 Egyptian Fractions
158
6.5 Ancient Chinese and Arabic Numerals
161
Xll
Illustrations
6.6 Representation of a Lune
165
6.7 Conic Sections
168
6.8 Evolution of Arabic Numerals
171
7.1 A Trephined Skull
181
7.2 Meridian Lines and Acupuncture Points for the Gallbladder 195
7.3 Aesculapius's Cacluceus and the AMA Caduceus Symbols
199
8.1 Clay Pottery Lamp—circa 800
B.C.E.
224
8.2 Herodian Oil Lamp—circa 100 C.E.
225
8.3 Egyptian Lock
226
8.4 Beehive Kiln
230
8.5 Potter's WTieel—circa 1900
232
B.C.E.
8.6 Low Whorl Drop Spindle
239
8.7 Vertical Loom
241
9.1 Bronze Age Collar
250
10.1 Vernal and Autumnal Equinoxes
277
10.2 Mayan Calendar
278
10.3 Julian Calendar
282
10.4 The Shadow Clock
290
10.5 The Ancient Water Clock
291
11.1 Antler Horn Harpoons, circa 6000
B.C.E.
299
11.2 Bronze Age Arrowheads and Flint Dagger
300
11.3 Roman Sickle and Vallus
304
11.4 Querns
306
11.5 Akkadian Bronze Helmet
311
11.6 The Bow Catapult
313
11.7 Assyrian Mobile Assault Tower
317
12.1 Three Types of Wheels and Two Types of Axles
324
12.2 Penteconter, Bireme, and Trireme
342
12.3 Chinese Rudder
346
Table
10.1 Months of the Year
285
SERIES FOREWORD
The material contained in five volumes in this series of historical
groundbreaking experiments, discoveries, and inventions encompasses
many centuries from the pre-historic period up to the twentieth century. Topics are explored from the time of pre-historic humans, the age
of classical Greek and Roman science, the Christian era, the Middle
Ages, the Renaissance period from the years 1350 to 1600, the beginnings of modern science of the 17 th century, and great inventions, discoveries, and experiments of the 18 th and 19 th centuries. This historical
approach to science by Greenwood Press is intended to provide students with the materials needed to examine science as a specialized discipline. The authors present the topics for each historical period
alphabetically and include information about the women and men
responsible for specific experiments, discoveries, and inventions.
All volumes concentrate on the physical and life sciences and follow
the same historical format that describes the scientific developments of
that period. In addition to the science of each historical period, the
authors explore the implications of how historical groundbreaking
experiments, discoveries, and inventions influenced the thoughts and
theories of future scientists, and how these developments affected people's lives.
As readers progress through the volumes, it will become obvious that
the nature of science is cumulative. In other words, scientists of one historical period draw upon and add to the ideas and theories of earlier
periods. This is evident in contrast to the recent irrationalist philosophy
of the history and sociology7 of science that views science, not as a
unique, self-correcting human empirical inductive activity, but as just
another social or cultural activity where scientific knowledge is conjectural, scientific laws are contrived, scientific theories are all false, scien-
xiv
Series Foreword
tine facts are fickle, and scientific truths are relative. These volumes
belie postmodern deconstructionist assertions that no scientific idea
has greater validity than any other idea, and that all "truths" are a matter of opinion.
For example, in 1992 the plurality opinion by three jurists of the U.S.
Supreme Court in Planned Parenthood v. Case restated the "right" to abortion by stating: "at the heart of liberty is the right to define one's own concept of
existence, of meaning of the universe, and of the mystery of human life. "This is
a remarkable deconstructionist statement, not because it supports the
right to abortion, but because the Court supports the relativistic premise that anyone's concept of the universe is whatever that person wants
it to be, and not what the universe actually is based on: what science has
determined by experimentation, the use of statistical probabilities, and
empirical inductive logic.
When scientists develop factual knowledge as to the nature of nature
they understand that "rational assurance is not the same thing as perfect certainty." By applying statistical probability to new factual data
this knowledge provides the basis for building scientific hypotheses,
theories, and laws over time. Thus, scientific knowledge becomes selfcorrecting as wTell as cumulative.
In addition, this series refutes the claim that each historical theory is
based on a false paradigm (a methodological framework) that is discarded and later is just superseded by a new more recent theory also
based on a false paradigm. Scientific knowledge is of a sequential nature
that revises, adds to, and builds upon old ideas and theories as new theories are developed based on new knowledge.
Astronomy is a prime example of how science progressed over the
centuries. Lives of people who lived in the pre-historical period w7ere
geared to the movement of the sun, moon, and stars. Cultures in all
countries developed many rituals based on observations of how nature
affected the flow of life, including the female menstrual cycle, their
migrations to follow food supplies, or adaptations to survive harsh winters. Later, after the discovery of agriculture at about 8000 or 9000
B.C.E., people learned to relate climate and weather, the phases of the
moon, and the periodicity of the sun's apparent motion to the Earth as
these astronomical phenomena seemed to determine the fate of their
crops.
The invention of bronze by alloving first arsenic and later tin with
copper occurred in about 3000 B.C.E. Much later, after discovering how
to use the iron found in celestial meteorites and still later, in 1000 B.C.E.
when people learned how to smelt iron from its ore, civilization entered
Series Foreword
xv
the Iron Age. The people in the Tigris-Euphrates region invented the
first calendar based on the phases of the moon and seasons in about
2800 B.C.E. During the ancient and classical Greek and Roman periods
(about 700 B.C.E. to A.D. 100) mythical gods were devised to explain what
was viewed in the heavens or to justify their behavior. Myths based on
astronomy, such as the sun and planet gods as well as Gaia the Earth
mother, were part of their religions affecting their way of life. This
period was the beginning of the philosophical thoughts of Aristotle and
others concerning astronomy and nature in general that predated modern science. In about 235 B.C.E. the Greeks first proposed a heliocentric
relationship of the sun and planets. Ancient people in Asia, Egypt, and
India invented fantastic structures to assist the unaided eye in viewing
the positions and motions of the moon, stars, and sun. These instruments were the forerunners of the invention of modern telescopes and
other devices that made modern astronomical discoveries possible.
Ancient astrology was based on the belief that the positions of bodies in
the heavens controlled one's life. Astrology is still confused with the science of astronomy, and it still is not based on any reliable astronomical
data.
The ancients knew that a dewdrop of water on a leaf seemed to magnify the leaf's surface. This led to invention of a glass bead that could
be used as a magnifying glass. In 1590 Zacharias Janssen, a spectaclemaker, discovered that two convex lenses, one at each end of a tube,
increased the magnification. In 1608 Hans Lippershey's assistant
turned the instrument around and discovered that distant objects
appeared closer, thus the telescope was discovered. The telescope has
been used for both navigation and astronomical observations from the
17th century up to the present time. The inventions of new instruments, such as the microscope and telescope, led to new discoveries
such as the cell by Robert Hooke and the four moons ofJupiter by Galileo, who made this important discovery that revolutionized astronomy
with a telescope of his own design and construction. These inventions
and discoveries enabled the expansion of astronomy from an ancient
"eyeball" science to an ever-expanding series of experiments and discoveries leading to many new theories about the universe. Others
invented and improved astronomical instruments, such as the reflecting telescope combined with photography, the spectroscope, and
Earth-orbiting astronomical instruments resulting in the discovery of
new planets, galaxies, and new theories related to astronomy and the
universe in the 20 th century. The age of "enlightenment" through the
18th and 19th centuries culminated in an explosion of new knowledge
xvi
Series Foreword
of the universe that continued through the 20 th and into the 21 s t centuries. Scientific laws, theories, and facts we now know about astronomy
and the universe are grounded in the experiments, discoveries, and
inventions of the past centuries, just as they are in all areas of science.
The books in the series Groundbreaking Scientific Experiments,
Inventions and Discoveries through the Ages are written in easy to
understand language with a minimum of scientific jargon. They are
appropriate references for middle and senior high school audiences, as
well as for the college level nonscience major, and for the general public interested in the development and progression of science over the
ages.
Robert E. Krebs
University of Illinois at Chicago
INTRODUCTION
According to the big-bang theory, the universe was formed about 14 to
15 billion years ago. The solar system and planets, including Earth, were
formed about 4.5 billion years ago. And the first primitive organic matter and archaebacteria appeared on Earth about 3.5 to 4 billion years
ago. During the Mesozoic Era, about 150 million to 250 million years
ago, small primitive mammals existed along with the more dominant
dinosaurs. Once the dinosaurs became extinct, around the beginning
of the Cenozoic Era 65 million years ago, mammals, particularly large
mammals, flourished. It is estimated that about 200,000 species of mammals existed in the distant past, and about 6,500 species of protoprimates are presumed to have existed at one time. Today, biologists
recognize only about 200 species of living primates. Thus, only about
3.8 percent of all the primate species that lived throughout the Cenozoic Era (65 million years ago to the present) still exist.
Our early ancestors' entry onto the scene came as late as 4 to 5 million
years ago when a small African hominid emerged, now referred to as Australopithecus. It was not until about 2 million years ago that the Homo genus
evolved as the more advanced Homo habilis. Evolution then produced the
even more advanced Homo erectus about 1.8 million years ago. Homo sapiens, the branch of hominids to which humans belong, emerged about
250,000 to 400,000 years ago. However, the subspecies Homo sapiens sapiens, the hominids that most closely resemble modern humans, appeared
only about 120,000 years ago. The Cro-Magnon culture that closely resembled modern-day humans is only about 40,000 years old. Homo sapiens
(modern man) is the only species of the Homo genus still in existence.
This raises the question, "What is ancient?" Ancient means "old" or
"archaic." These are subjective terms indicating that ancient c^w actually
mean anytime from the beginning of the universe to the appearance of
xviii
Introduction
mammals on the Earth, to the comparatively recent days of the horse
and buggy, or even to last year's fashions. Some children may think of
their parents as "ancient" a n d / o r their grandparents as very "ancient."
Anthropologists may consider events prior to recorded history in
Mesopotamia or Egypt as ancient. For our purposes, "ancient" means
when humans first used fire, developed tools and weapons, or discovered how to control and alter their environment for their own purposes
and needs (e.g., through agriculture). Early humans no doubt
"invented" useful objects by applying learned technologies. They discovered many things about their environment, and conducted early
experiments by trial-and-error methods. Modern humans, by the way,
are still discovering things about their universe, inventing objects for
their use to control their environment, and experimenting by using
some of the same methods employed by our ancient ancestors.
Ancient humans also further developed the ability to categorize and
list things that could be useful a n d / o r harmful. This required a degree
of abstracting, generalizing, stereotyping, predicting, and relating cause
with effect beyond that which other animals were capable of. Also
involved was the development of a larger brain, an advanced level of
intelligence, and consciousness beyond their primate ancestors, which
most likely developed in conjunction with the improved flexible forearm and hand with opposable thumb. There is evidence that primates
other than ancient humans also developed some simple tools and
weapons for securing food and protection from predators. But early
humans, with their larger brains, advanced intelligence, and opposable
thumbs, developed the technology for producing improved stone tools
and weapons. The "ancient" period addressed in this book includes the
span of history of early discoveries, experiments, and inventions from
the Stone Age, the Bronze Age, and the Iron Age, through early civilizations in Africa, Asia, the Middle East, Europe, and the Americas to the
ancient and classical Greek and Roman civilizations. The "ancient"
period for this book also includes the early Christian Era up to about
476 C.E., which is the accepted date for the fall of the Roman Empire.
(Note: C.E. represents the "Common Era," which replaces A.D.; B.C.E.
stands for "Before the Common Era" and replaces B.C; and B.P. refers to
"Before the Present.")
Many ancient discoveries provided the background for additional discoveries, inventions, and experiments during the later Middle Ages and
Renaissance. These in turn provided the background for the advancement of science and technology during the Age of Enlightenment, and
even now ancient concepts affect the nature of our current social, eco-
Introduction
xix
nomic, and political lives. For instance, prehistoric domestication of
plants and animals and the ancient practice of selecting the "best" seeds
to store and plant, or the "best" animals to breed, led to the nature of
inherited characteristics discovered by Gregor Mendel, the concept of
organic evolution by Darwin, the nature of the DNA double helix by
Watson and Crick, and, more recently, the nature of the entire human
genome, which has great promise in potential cures for many human illnesses. (Words in bold type can be found in the Glossary.) Thus, the
ancient knowledge of breeding plants and animals is the forerunner of
modern genetic engineering. Another example is the ancient Greek
concept of the indestructible and indivisible "atom" devised by Leucippus and Democritus, which has been contemplated, revised, and reconfirmed by scientists through experiments that led to discoveries
concerning the nature of matter. New experiments are providing information regarding the structure of the atom and its ultimate parts. By
inventing new instruments and conducting new experiments, theoretical particle physicists expect to discover the "ultimate" particle of matter and sooner or later arrive at the "Grand Unification Theory" (GUT)
or the "Theory of Everything" (TOE) for the universe. Archaeologists
have traced the progressive inventions of ancient humans in developing
stone, and later metal, tools and weapons from simple handheld sharpened stones, to attaching handles to stones and metal blades, to using
pointed spears and arrows as missiles. These early tool and weapon
inventions not only improved over time, but also affected and changed
our lives over many centuries. Ultimately, the ancient concept of the
atom and ancient missiles (spears) were combined (nuclear weapons
carried by ICBMs), altering the nature of society and providing the possibility of ending civilization as we know it. These and many other
ancient discoveries, inventions, and experiments are presented in this
book.
This volume on the Ancient World for the series Groundbreaking Scientific Experiments, Inventions and Discoveries through the Ages gives
credence to the concept that science is not always clean and precise,
especially in its formative stages. This reference book is designed for
high school and undergraduate students, as well as the general public,
who are interested in learning more about the foundations of science
and technology that our early ancestors built and that succeeding generations added to and improved.
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1
AGRICULTURE AND
ANIMAL
DOMESTICATION
Background and History (Agriculture)
Given the timeline for the evolution of our species that is described in
this book's introduction, it is extraordinary that all of the agricultural,
technological, and cultural advancements that have so enriched our
lives have taken place since the Neolithic Period that began around
10,000 B.C.E., following the retreat of the last ice age. Fossils and artifacts from periods prior to the Neolithic Period indicate that archaic
humans, even those who more closely resembled modern-day humans,
fashioned stones to use as knives and scrapers. This was a hunting and
gathering society that used animals for nourishment, clothing, and in
some cases shelter, and relied on the flora of the period, such as berries
and nuts, as a supplement to their diet and for medicinal uses. Scholars
believe that the development of modern humans progressed in four
stages: (1) hunting/gathering; (2) nomadic, with some domestication
of animals; (3) farming; and finally, (4) civilization.
Agriculture, sometimes referred to as settled farming, is defined as
the deliberate clearing and cultivating of arable soil, planting and covering seeds, irrigating the fields, weeding unwanted or harmful vegetation, harvesting the resultant crops, and finally storing those crops for
future use. Its inception has had more of an impact on our environment
and culture than any other institution. Historians have not determined
an exact date for the beginning of agriculture or farming. Most agree
that farming began in several places and in different forms. For example, hunters and gatherers during the Upper Paleolithic Period of
40,000 years ago engaged in hobby or part-time farming. It was not a
full-time endeavor for them. Early humans followed herds of game, primarily mammoths and mastodons, across the plains that opened up
when glaciers receded. They then settled into temporary communities
2
Groundbreaking Scientific Experiments, Inventions, and Discoveries
during the hunt. Using a wooden stick or perhaps an antler from a slain
elk or deer, early humans scratched at the soil and "planted" the seeds
from plants native to that area and then ate the harvest. It may have
been more serendipitous than planned, but it provided them with a
source of food in addition to what they could gather or kill. (Humans
are one of the few omnivorous mammals. Both plant and animal proteins are staples of our diets, yet humans are able to survive on one without the other.) These communities were short-lived as early humans,
who were basically nomads, traveled on to the next hunting site.
The same was true for early farmers. As the soil was exhausted from
overcultivation, humans simply moved on to another location, leaving
the remnants and debris of their labors in their wake. At this time in our
history, humans did not behave as conservationists of either the land or
the animals who populated the continents. For instance, one theory
called the Pleistocene Overkill suggests that the predation and indiscriminate hunting practices of early humans destroyed vast numbers of
species of large mammals. During the climatic and geographic cataclysm of the last ice age, humans migrated from the African continent,
where hominids originated, through Eurasia and over the Beringia land
bridge between Siberia and Alaska into the Americas. As humans
learned to build and sail boats, the Australian continent, the Pacific
Islands, and South America also became populated through migrations.
Archaeological evidence confirms that the first settlers on New Guinea
and Australia reached these areas by boat approximately 40,000 B.C.E.
The movement of the human population from one continent to
another took place several times over centuries. For example, most
experts agree that humans were in the Americas at least 11,000 years
ago, but there is evidence to suggest that the Americas may have been
populated by early humans as early as 21,000 B.C.E.
The retreat of the glaciers left the landscape of the Earth with vast,
grassy plains, fertile river valleys, rivers and lakes with stocks of fish and
aquatic life, and woodlands populated with trees and plants and abundant communities of wildlife. Historic evidence suggests that the earliest forms of rice and millet were cultivated in southeast Asia about
10,000 B.C.E.—roughly 12,000 years B.P. (Before the Present). Alfalfa,
the oldest forage crop, reportedly was raised at about the same time in
what is present-day Syria. Thus, many experts place this as the time
when agriculture became viable. Others hypothesize that intensive agriculture began in the Middle East between 9000 and 7000 B.C.E.. All
agree, however, that life was essentially short and brutal during this
period. Characteristic of our species, early humans adapted in different
Agriculture and Animal Domestication
3
ways to a particular environment, utilizing the plant and animal
resources concentrated in that area. That adaptation did not mean that
life was easier for them than for their nomadic counterparts. On the
contrary, in many respects life was harder for early farmers. Dependent
on the variables of climate and limited by what could actually be grown,
farmers had poorer diets and suffered from more diseases while working harder. They also had to contend with pests who ate and damaged
the growing crops. Yet, this somew7hat more stable lifestyle was conducive to producing more offspring, thus their numbers grew rapidly.
Larger populations of farmers could support more than merely those
who worked the crops. However, their primitive methods of farming
and animal management exhausted the land in just a few seasons, which
forced these early settlers to move on to new territories, usually usurped
from the nomadic hunters. This great antagonism between farmers and
hunters was the impetus that eventually resulted in the replacement of
the hunting/gathering lifestyle with that of the cultivators of the land.
(The conflict of interest between farmers and cattle raisers continued
into modern times in the western portion of the United States.) This
change in lifestyle revolutionized the human condition and laid the
foundation for modern civilization including commerce, industry, the
arts, and science. Durable houses would be constructed and various
tools and implements would be developed to ease the labor of the
farmer and increase the production of crops. Crops would be grown not
only to feed the farmers but also for the members of other communities, to maintain animal populations for human consumption and
labor, to supply building materials and writing materials—in other
words, everything needed by humans to supply their ever-expanding
civilization and culture. Alfalfa is an example of a crop whose uses were
manifold. It is an excellent feed for animals (as well as humans). It nourishes the soil and augments crop production, while possessing medicinal benefits as well.
Farming certainly spread with the migration of people across the
continents, either on foot or by boat across the oceans, since our ancestors of some 30,000 years ago were first-rate sailors. Knowledge of agricultural practices, primitive and more advanced, often developed
independently without the transfer of knowledge from one society of
humans to another. This is believed to be the case in the Americas, for
example. In ancient times crops were indigenous to a particular region
or continent. However, when humans began to explore and conquer
other lands in later centuries, nonindigenous plants were then introduced and grown with varying degrees of success. The following