Evolution of Humans and Society – Prehistoric Period

Learning Objectives

• To understand the history of the world.
• To understand the evolution of humans.
• To learn about the different stages of prehistoric periods.
• Introduction

We live in an age of humans and technology. Today, mobile phones have brought the world into our hands. Through the knowledge and abilities gained by humans, such advanced technological development has become possible. Therefore, studying the continuous growth and development of humans from prehistoric times is considered a fundamental necessity of knowledge.

Knowledge about the prehistoric world has gradually developed. Through stone tools, language development, and other discoveries, we gain an understanding of early human life.

Concept

A concept is an idea or understanding that may vary from person to person.

Communication

Communication is the process of expressing ideas, experiences, and emotions through language. It is connected with the intellectual development of humans.

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1.1 Origin of the Earth and Geological Ages

Human history is closely related to the history of the Earth. Important information has been obtained from geology, archaeology, and biology regarding the Earth and its development.

The Earth was formed about 4.54 billion years ago. Gradually, conditions became suitable for the growth of living organisms. Later, plants and animals appeared. This created opportunities for the evolution of humans. Geologists have divided Earth’s history into eras, periods, and ages for better understanding.

Evolution of Human Beings

Human beings are one among millions of living organisms found on Earth. The scientific study of the origin and development of humans is called Human Evolution.

Early humans evolved from ape-like ancestors over millions of years. According to scientific studies, the process of human evolution took place gradually through different stages.

Stages of Human Evolution

Early ape-like ancestors existed around 600 to 542 million years ago.

Primitive vertebrates evolved during 542–251 million years ago.

Mammals developed during the later stages.

Human-like species evolved about 65 million years ago.

Australopithecus

The earliest human ancestors were called Australopithecus. They lived in Africa and were able to walk on two legs. Their brains were smaller compared to modern humans.

Homo Erectus

Later, Homo Erectus evolved. They were more intelligent, used simple tools, and learned to use fire.

Neanderthals

The Neanderthals were another group of early humans. They lived in caves, hunted animals, and used stone tools.

Homo Sapiens

Modern humans belong to the species Homo sapiens. They developed advanced thinking ability, language, culture, agriculture, and civilization.

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Importance of Studying Human Evolution

Studying human evolution helps us understand:

The origin and development of human beings.

The similarities between humans and other living organisms.

Changes in human life and culture over time.

The development of intelligence, language, and social life.

Evolution and Prehistoric Age

The prehistoric age is divided into different stages based on the tools used by humans.

Stone Age

Humans mainly used stone tools during this period. It is divided into:

1. Old Stone Age

2. Middle Stone Age

3. New Stone Age

Metal Age

Later, humans learned to use metals such as:

Copper

Bronze 

Iron

This development led to the growth of civilizations and modern society.

Anthropology:

The study of the origin and development of rocks, the earth’s surface, and the relationships formed due to natural and cultural activities.

Ancient Museums:

The museum established by Ennigaldi in Mesopotamia around 530 BCE is considered one of the earliest museums. Ennigaldi was the daughter of Nabonidus, the Neo-Babylonian king.

The Capitoline Museum in Italy is regarded as the oldest surviving museum.

The Ashmolean Museum at Oxford University is considered the world’s oldest university museum. It was established in 1677 CE.

Charles Darwin and Human Evolution

The theories of Herbert Spencer and Charles Darwin (1809–1882 CE) scientifically explained human origin through the concepts of “natural selection” and “survival ability.”

Darwin’s famous works:

On the Origin of Species – published in 1859

The Descent of Man – published in 1871

Natural Selection

Through this process, organisms that are better adapted to nature survive and produce more offspring.

Adaptation

Organisms adapt themselves according to the surrounding environment and conditions.

Variations.

Differences found among individuals of the same species are called variations.

Heredity:

The transfer of characteristics from parents to offspring is called heredity.

Cultural Evolution:

Human beings gradually developed language, religion, culture, and social institutions through cultural evolution.

1.3 Archaeological and Anthropological Sources for the Study of History

To understand the life of ancient people, historians depend on archaeological and anthropological evidence. Archaeology studies ancient objects, monuments, tools, inscriptions, coins, pottery, and remains left behind by humans.

Importance of Archaeology

Archaeological findings help us understand:

Human life and culture

Agriculture and settlement patterns

Religion and social organization

Technology and trade

Human Evolution

Humans evolved from early hominids over millions of years. Scientists believe that Africa is the birthplace of early human beings.

Stone Age

Humans used stone tools during the early stages of civilization. Archaeologists have identified several phases of the Stone Age based on the types of tools used.

Important Note:

The fossil remains of early humans found in Africa are considered to belong to Homo sapiens. Based on these pieces of evidence, it is believed that the history of humans dates back nearly 64,000 years. Among the tools used by prehistoric people, stone tools and bone tools were important.

Humans moved from place to place and adapted themselves to different environments. By observing nature and animals around them, they learned many things. They gradually understood the importance of food, shelter, and protection from enemies.

About 26 million years ago, in Africa, a group of mammals called primates evolved. Among these, two-legged hominids/gorillas emerged around 2 million years ago. These gradually developed intelligence and became the earliest humans. They later spread across Asia and Africa.

Important Note

Chimpanzees and bonobos (which resemble chimpanzees) are our closest relatives.

Early Human Evolution

In Africa, fossils and evidence related to early humans have been discovered. The map shows the important sites where such evidence was found.

Homo Species

“Homo” refers to the human species and includes different groups of humans.

Hominids

“Hominids” refers to human-like primates such as gorillas, chimpanzees, and australopithecines, from which humans evolved.

Captions in the Images

Fossils of early humans (Australopithecus)

Human fossils found in Africa 

Sources of Energy and Their Conservation:

Sunlight, flowing water, wind energy, biomass, fossil fuels, and nuclear energy are the major sources of energy. Fossil fuels, nuclear energy sources, and natural gas are the main energy sources used today. Thermal power plants, hydroelectric power plants, and nuclear power plants generate electricity using these energy sources.

Conventional Energy Sources:

The energy sources mainly used today are called conventional energy sources. These provide about 3.3 million megawatts of electricity. Thermal power plants are the primary conventional energy sources. They produce around 2 to 2.6 million megawatts of electricity. Thermal power plants use coal, oil, and natural gas as fuels. Due to their use, environmental pollution and global warming problems are increasing.

Coal (Coal) as an Energy Source:

Coal is the most commonly used fossil fuel in thermal power plants. It is mainly formed from plants that were buried under the earth millions of years ago.

In India, coal and uranium reserves together amount to about 1.8 million tons. However, their excessive use is reducing the reserves and causing environmental problems. Therefore, these resources should be used carefully.

These resources are limited in nature and are called non-renewable energy sources (conventional energy sources). Once used, they cannot be reproduced quickly. It is estimated that coal reserves in India may last for only about 250,000–60,000 years.

Non-Conventional Energy Sources

Nuclear Energy:

Atoms contain a central nucleus. Energy released from atoms is called nuclear energy. Nuclear reactors use this energy.

Biomass:

Energy obtained from living organisms is called biomass energy (such as wood, crop waste, and cow dung).

Solar Energy:

The energy and heat obtained from the Sun are called solar energy. Solar energy is the most important source of renewable energy. It is used for generating electricity, heating water, drying agricultural products, and cooking.

Solar cookers and solar cells are used in homes, schools, hospitals, and industries. Solar energy is widely used in villages and remote areas.

Biomass energy is inexpensive and environmentally friendly. It is mainly used as fuel in villages and rural areas.

Energy resources are classified into renewable and non-renewable resources based on their availability and usage.

Resources that can be reused and replenished are called renewable resources. Wind energy, solar energy, and hydroelectric power are examples of renewable resources.

Wind Energy:

Wind power plants produce about 3,98,000 MW of electricity worldwide. About 3 lakh MW of electricity is generated using wind energy.

Hydroelectric Power:

The electricity generated by the force of flowing water is called hydroelectric power.

The electricity generated from water resources is renewable and environmentally friendly.

Scientists are researching and developing energy resources from waves, tides, and ocean currents.

Research is also being conducted on renewable energy resources such as algae and microorganisms. These resources are considered future energy sources.

Radioactive Elements:

Energy is produced from radioactive substances. Uranium and thorium are the main radioactive elements used for electricity generation.

Radioactive Energy:

Radioactive elements are found underground. These elements release energy continuously. Uranium produces about 3,85,000 MW and thorium about 1,98,000 MW of energy.

The total estimated uranium reserves in India are about 28,000 tonnes.

These resources are limited and expensive. Hence, they should be used carefully and conserved.

Non-Conventional Energy Sources

Nuclear Energy:

Atoms contain a central nucleus. Energy released from atoms is called nuclear energy. Nuclear reactors use this energy.

Biomass:

Energy obtained from living organisms is called biomass energy (such as wood, crop waste, and cow dung).

Solar Energy:

The energy and heat obtained from the Sun are called solar energy. Solar energy is the most important source of renewable energy. It is used for generating electricity, heating water, drying agricultural products, and cooking.

Solar cookers and solar cells are used in homes, schools, hospitals, and industries. Solar energy is widely used in villages and remote areas.

Biomass energy is inexpensive and environmentally friendly. It is mainly used as fuel in villages and rural areas.

Energy resources are classified into renewable and non-renewable resources based on their availability and usage.

Resources that can be reused and replenished are called renewable resources. Wind energy, solar energy, and hydroelectric power are examples of renewable resources.

Wind Energy:

Wind power plants produce about 3,98,000 MW of electricity worldwide. About 3 lakh MW of electricity is generated using wind energy.

Hydroelectric Power:

The electricity generated by the force of flowing water is called hydroelectric power.

The electricity generated from water resources is renewable and environmentally friendly.

Scientists are researching and developing energy resources from waves, tides, and ocean currents.

Research is also being conducted on renewable energy resources such as algae and microorganisms. These resources are considered future energy sources.

Radioactive Elements:

Energy is produced from radioactive substances. Uranium and thorium are the main radioactive elements used for electricity generation.

Radioactive Energy:

Radioactive elements are found underground. These elements release energy continuously. Uranium produces about 3,85,000 MW and thorium about 1,98,000 MW of energy.

The total estimated uranium reserves in India are about 28,000 tonnes.

These resources are limited and expensive. Hence, they should be used carefully and conserved.

Importance of Saving Energy:

Saving energy means reducing unnecessary use of energy and using it efficiently. This helps in conserving natural resources.

By using renewable energy sources and reducing wastage, we can protect the environment and ensure energy availability for future generations.

Simple measures such as switching off electrical appliances when not in use and using energy-efficient devices help in energy conservation.

It is estimated that about 3,00,000 MW of electricity is wasted annually due to improper use. Out of this, about 60,000 MW can be saved through proper conservation methods.

Saving energy means reducing unnecessary use of energy and using it efficiently. This helps in conserving natural resources.

By using renewable energy sources and reducing wastage, we can protect the environment and ensure energy availability for future generations.

Simple measures such as switching off electrical appliances when not in use and using energy-efficient devices help in energy conservation.

It is estimated that about 3,00,000 MW of electricity is wasted annually due to improper use. Out of this, about 60,000 MW can be saved through proper conservation methods.