Human Being

Human beings, unlike any other creatures, use art and lan­guage to preserve a knowledge of history. The museum guide is describing ancient Chinese buildings and ways of life.

Human cultural development - Human cultural development can be divided into three phases. The earliest societies, hunted wild animals and gathered wild plants for food. Agricultural societies, controlled their food sources by farming. Industrial societies, use advanced technology, resulting in both major achievements and complex problems.

Physical differences between human beings and apes - The bodies of human beings are suited to walking on two feet. On the other hand, the bodies of apes are suited to walking on four limbs or climbing. Some of the re­sulting physical differences between people and apes.

The human head rests on the spinal column. A gorilla's head hangs from the end of the spinal column.

Human beings have a curve in the lower spine to absorb the stress of walking on two feet. A gorilla's lower spine is straight.

A human being has shorter arms than legs. A gorilla's arms are longer than its legs.

The human foot is used chiefly for support of the body. A gorilla's feet can grasp things as well as support the animal's body.           

Human being has the most highly developed brain of any animal. The human brain gives people many special abilities, the most outstanding of which is the ability to speak. Language has enabled human beings to develop culture, which consists of ways of behaving and think­ing. These ways are passed on from generation to gen­eration through learning. Culture also includes technol­ogy—that is, the tools and techniques invented by people to help satisfy their needs and desires. The richness and complexity of human culture distinguish human beings from all other animals.

The human brain helps make people the most adapt­able of all creatures. They behave with the most flexibil­ity and in the greatest variety of ways. The human body is highly adaptable because it has few specialized fea­tures that could limit its activities. In contrast, a seal has a body streamlined for swimming, but it has difficulty moving about on land. People cannot swim as well as a seal, but they can also walk, run, and climb. Human adaptability enables people to live in an extremely wide variety of environments—from the tropics to the Arctic.

People are inquisitive and have long sought to under­stand themselves and their place in the world. Through­out much of human existence, religion has helped pro­vide such understanding. All societies have assumed that one or more gods influence their lives and are re­sponsible for their existence. Since ancient times, phi­losophy [the study of truth and knowledge) has also pro­vided definitions of what it means to be human.

Today, religion and philosophy remain important parts of people's efforts to understand the nature of human existence. But many other fields of study also help human beings learn about themselves. For exam­ple, anthropology is the study of human cultures and of human physical and cultural development. Linguistics is the scientific study of language. Specialists in psychol­ogy study human and animal behaviour and mental processes. Sociology deals with the groups and institu­tions that make up human societies, and history is the study of past human events. Each of these fields has a separate article in World Book.

This article describes the physical and cultural char­acteristics that distinguish human beings from other ani­mals. It also traces human physical and cultural develop­ment. For more information on the life of early human beings, see Prehistoric people.

Characteristics of human beings

Scientific classification. Biologists classify all living things in groups, including class, order, family, genus, and species. Human beings belong to the class of ani­mals called mammals. There are about 4,000 species of mammals, including such animals as cats, dogs, ele­phants, and otters. All mammals have a backbone, hair, four limbs, and a constant body temperature. Female mammals are the only animals with special glands that produce milk for feeding their young.

Human beings, along with apes, monkeys, lemurs, and tarsiers, make up the order of mammals called pri­mates. Scientists classify human beings and apes in the superfamily Hominoidea. The family Hominidae consists of human beings and their closest prehuman ancestors.

Human beings are the only living members of a genus called Homo, the Latin word for human being. This genus consists of one living species—Homo sapiens-and several extinct human species that are known only through fossil remains. The Latin words Homo sapiens mean wise human being. All existing peoples belong to the subspecies Homo sapiens sapiens.

Physical characteristics. Human beings and the other primates share many physical features. For example, both human beings and apes rely on their excellent vision for much of their information about the environment. They have large eyes, sensitive retinas, and stereoscopic vision (the ability to perceive depth). Human beings and apes also have a highly developed nervous system and a large brain. Human beings and many other primates have long, flexible fingers and opposable thumbs, which can be placed opposite the fingers for grasping. In addition, their fingers and toes have nails instead of claws.

Many of the physical characteristics that distinguish human beings from other primates are related to the ability of people to stand upright and walk on two legs. This ability chiefly requires long, powerful legs. The human rump has strong muscles that propel the body forward and balance the trunk alternately on each leg when a person walks. In contrast, apes spend most of their time climbing and swinging in trees or walking on all four limbs. Their rumps have relatively weak muscles and their arms are longer and stronger than their legs.

The human spine, unlike the spine of any other animal, has a curve in the lower back. This curve helps make upright posture possible by placing the body's centre of gravity directly over the pelvis. The human foot is also specially adapted for walking on two legs. Apes use all four limbs to support their weight, and they can grasp objects almost as well with their feet as with their hands. In human beings, however, the feet support the entire weight of the body, and the toes have little ability to grasp or to move independently.

The human brain is extremely well developed and at least twice as large as any ape's brain. Because of the brain's size, the human skull is rounder than any other primate's skull.

Human beings live longer and develop more slowly than other primates. The human life span varies from an average of about 40 years in many developing countries to more than 70 years in most industrial nations. A human infant is born completely helpless and depends on its parents for many years. Most human beings reach full maturity only between 18 and 25 years of age. Slow growth and development allow for a much longer pe­riod of learning and brain growth than exists in any other species.

Cultural characteristics. Some animals have simple aspects of culture. For example, young chimpanzees learn from older members of their group how to make some tools. They catch termites by peeling a twig and inserting it into a termite mound. They also chew leaves to make sponges for soaking up water to drink.

Certain animals, including apes and monkeys, com­municate by making a wide variety of sounds. These sounds express emotion and may communicate simple messages, but they apparently do not symbolize any ob­ject or idea. Language distinguishes human culture from all forms of animal culture. Through elaborate use of symbols, language enables people to express complex ideas and to communicate about objects and events that are distant in time and place. By using language, human beings have developed the ability to reason and to solve problems on a far higher level than any other animal. Language also enables human beings to pass on knowl­edge and skills from generation to generation.

Human physical development

The Bible describes how God created the world and all its living things, including the first human beings, in six days. Many people accept this description as fact.

Evidence from fossils has convinced most scientists that human beings developed over millions of years from ancestors that were not completely human. How­ever, the fossil record does not yet provide enough in­formation to trace human development in detail. As a re­sult, not all experts agree on how human beings developed. This section describes human physical de­velopment as most anthropologists believe it occurred.

Prehuman ancestors. Anthropologists believe human beings, chimpanzees, and gorillas all developed from a common ancestor that lived from 4 million to 10 million years ago. Many scientists once thought that the earliest direct ancestor of human beings was Ramapithecus, which lived from 8 million to 14 million years ago. During the 1970's and early 1980's, however, discov­eries of Ramapithecus fossils suggested that the crea­ture was an ancestor of the orangutan, a kind of ape.

More than 4 million years ago, a humanlike creature called Australopithecus appeared in Africa. Fossil re­mains of the australopithecine skeleton indicate that these creatures stood fully erect and walked on two legs. The australopithecines were about 120 to 150 cen­timetres tall and had a brain about a third the size of a modern human brain.

Early human beings. Most scientists regard the spe­cies Homo habilis (skilful human being) as the first type of human being. These primitive people appeared about 2 million years ago in Africa and are believed to have developed from the australopithecines. Archaeological evidence shows that Homo habilis used stone tools. Homo habilis fossils have been found at Lake Turkana, Kenya, and other areas in eastern Africa.

Most scientists believe that Homo habilis developed into a more advanced type of prehistoric human being known as Homo erectus (erect human being). Homo erectus appeared about 1 ^ million years ago in Africa and spread to Asia and Europe. It had a larger brain than its ancestors. From the neck down, Homo erectus re­sembled the human beings of today. But it had a low forehead and a large jaw like Homo habilis and the aus­tralopithecines. Homo erectus made and used a wider variety of stone tools than Homo habilis. It learned how to make fire about 500,000 years ago and was probably the first human species to do so. Fossils indicate that Homo erectus may have hunted large animals, and this sort of hunting would have required planning and coop­eration.

Human beings of today. The first members of the species Homo sapiens (wise human being) appeared be­tween about 400,000 and 300,000 years ago. These peo­ple basically resembled Homo erectus but had a larger brain and smaller jaws and teeth. As time passed, Homo sapiens developed a rounded skull and long, straight limbs. Homo sapiens looked like today's human beings by at least 40,000 years ago, and perhaps as early as 100,000 years ago. Most anthropologists classify all people who have lived in the last 40,000 years as Homo sapi­ens sapiens.

Human cultural development

Human culture has developed in three major phases. These phases have been based on (1) hunting and gath­ering societies, (2) agricultural societies, and (3) indus­trial societies.

Hunting and gathering societies. For almost the entire prehistoric period of human existence, people lived by hunting game and gathering fruit, nuts, roots, seeds, and other plant foods. Archaeological evidence suggests that the hunters and gatherers lived in widely separated groups of 25 to 50 people. These primitive people wandered over large areas in search of food. They lived in harmony with their environment and used their natural resources efficiently.

The first inventions probably included weapons and cutting tools for butchering animals, plus containers for gathering plant foods. As people improved their hunt­ing skills, they obtained large amounts of meat by killing huge mammals, including elephants.

Agricultural societies became possible after people began to domesticate wild animals and plants about 9000 B.C These farming activities greatly increased the amount of food available in any area. Permanent villages started to appear, and then towns and cities developed. The larger and more dependable supply of food sup­ported a continually increasing population.

Agriculture made it unnecessary for everyone to help in the production of food. Some people became special­ists in other fields, such as manufacturing or trade. Gov­ernments were established and systems of writing were created. Thus, the invention of farming opened the way for the development of civilization.

Industrial societies appeared in their modern form during the A.D. 1700's, after people learned to run ma­chinery with energy from coal and other fuels. Today, petroleum, coal, natural gas, and nuclear fuel furnish most of the energy used by industrial societies. These fuels have brought a great expansion of technology.

The processes and products developed by industry have greatly improved the standard of living for count­less people. These developments have also helped make possible many other advances, including tremen­dous increases in human knowledge and in the variety of artistic expression. But not all nations and economic classes have received the full benefits of industrial prog­ress. Industrial technology also has produced many neg­ative side effects. For example, its wastes pollute the en­vironment, and its production methods sometimes create monotonous, unfulfilling jobs.

Industrial societies today face many major challenges. New technologies must be developed to use the world's limited natural resources more efficiently. New, nonpol­luting sources of energy are needed. In addition, people must find ways to control population growth and to ex­tend the benefits of modern technology to all the world's people. Related articles. See Prehistoric people and its list of re­lated articles. See also the following articles: Ape, Culture, Primate, Civilization, Human body, Races and Human.