FY2009

Annual Report on the Environment/ Annual Report on the Sound Material-Cycle Society/ Annual Report on the Biodiversity

Our Responsibility and Commitment to Preserve the Earth – Challenge 25 –

Introductory Chapter

The Course of the Earth

— Where Is the World Headed and Where Does Japan

Find Itself? —

If we liken the history of the earth to one year, human history spans just about four hours. The history of mankind since the Industrial Revolution in the 18th century is equivalent to only about one second. In the rich and exquisite ecosystem that life born on the earth has built up over ages, humans have achieved amazing development by making use of a variety of resources. As a consequence of that development, however, human activities have grown to assume such proportions as to exponentially consume

## 1 Mankind Born on the Earth

Life is thought to have come into existence on this earth some 4 billion years ago. And then, unicellular bacteria are believed to have spread all over the earth, and in particular, cyanobacteria are known to synthesize organic matter from water and carbon dioxide through photosynthesis and at the same time produce oxygen. In the Cambrian period (from 600 million years ago), the major phyla of multicellular animals that now exist are said to have come out en masse. Oxygen generated by underwater activities of photosynthetic organism built up in the atmosphere and the subsequent formation of the ozone layer blocked off ultraviolet rays and appears to have made it possible for living organisms to come ashore some 500 million years ago. Until then, land is believed to have been literally barren. Subsequently, fish species are said to have prospered in the Devonian period of the Paleozoic era (from some 410 million years ago) and then amphibian species in the Carboniferous period (from some 360 million years ago). During the mid-Triassic period, when the reptiles are believed to have extended their habitat to underwater and into the air, mammals came into existence, and ancestors of primates are believed to have been born about 85 million years ago. Some 65 million years ago, the extinction of dinosaurs and other giant reptiles created the opening in living space and then mammals are believed to have expanded their habitat explosively.

Regarding the evolution from apes to humans, the molecular evolutionary theory assumes that the phyletic line of gibbons became differentiated from the phyletic line that led to humans 18 million to 12 million years ago, and the phyletic line of orangutans differentiated 12 million years ago. Further, the natural blessings and alter the global environment in that “last second.” Where is the earth we live on heading?

In this Introductory Chapter, we go over the history of the earth and the history of mankind and give an overview of global trends, based on macro data, of changes in the world population, conditions of resources and economic activities in recent years, and also examine the situation in Japan. Further, we consider the impact on the global environment through an analysis of such trends.

phyletic line of gorillas differentiated eight million to four million years ago, and then the phyletic line of chimpanzees, which differ only 1-2% from humans in terms of DNA base sequence, is said to have diverged five million to four million years ago. The Homo genus is believed to have differentiated from the Australopithecine genus in Africa about two million years ago, and Homo sapiens, the modern humankind, is said to have appeared 400,000 to 250,000 years ago.

Many organism species have adapted themselves to changes in the environment by transforming their body shapes over many generations. However, the subsequent alteration of the environment by humans has been taking place much faster than the speed necessary for such adaptation. Humankind is also one of organism species, human beings are no different from other living organisms in that they cannot adapt themselves to the environment they are rapidly altering by transforming their body shapes.

Human beings are believed to have improved their living conditions in the course of evolution. For example, it is thought that the use of simple pebble tools increased the amount of quarries, and the economy of efforts to catch preys made their living easier. And archanthropines, using their advanced techniques to make stone implements, succeeded in attaching blades to pebble tools and making a fire. From the time of archaic humans to that of new humans, tools became diversified and techniques were refined, and rich mental activity is also believed to have developed. Primitive agriculture and livestock husbandry, which are thought to have started in the New Stone Age, made further advances in ancient times, and the invention of metalware has changed the