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Humankind has always been inquisitive, needing to understand why things behave in a certain way, and trying to link observation with prediction. For example, since prehistoric times we have observed the heavens and tried to make sense of the seasonal changes in the position of the sun, moon and stars.
Astronomers statue outside the Griffith Observatory, Los Angeles
In about 4000 BC, the Mesopotamians tried to explain their observations by suggesting that the Earth was at the centre of the Universe, and that the other heavenly bodies moved around it. Humans have always been interested in the nature and origins of this Universe.
But they weren't only interested in astronomy. The extraction of iron, which led to the Iron Age, is a chemical process which early metallurgists developed without understanding any of the science involved. Nevertheless, they were still able to optimise the extraction by trial and error.
Before this, copper and tin were extracted (which led to the Bronze Age) and later, zinc. Exactly how each of these processes was discovered is lost in the mists of time, but it is likely that they were developed using observation and experiment in a similar way to that used by today's scientists.
Early humankind also observed that certain plants could be used to treat sickness and disease, and herbal medicines were developed, some of which are still used by modern pharmaceutical companies to provide leads for new synthetic drugs.
The first people to try and develop the theory behind their observations were the Greeks: people such as Pythagoras, who concentrated on a mathematical view of the world. Similarly, Aristotle and Plato developed logical methods for examining the world around them.
It was the Greeks who first suggested that matter was made up of atoms - fundamental particles that could not be broken down further.
But it wasn't only the Greeks who moved science on. Science was also being developed in India, China, the Middle East and South America. Despite having their own cultural view of the world, they each independently developed materials such as gunpowder, soap and paper.
However, it wasn't until the 13th century that much of this scientific work was brought together in European universities, and that it started to look more like science as we know it today.
Progress was relatively slow at first. For example, it took until the 16th century for Copernicus to revolutionise (literally) the way that we look at the Universe, and for Harvey to put forward his ideas on how blood circulated round the human body. This slow progress was sometimes the result of religious dogma, but it was also a product of troubled times!
THE BIRTH OF MODERN SCIENCE
It was in the 17th century that modern science was really born, and the world began to be examined more closely, using instruments such as the telescope, microscope, clock and barometer. It was also at this time that scientific laws started to be put forward for such phenomena as gravity and the way that the volume, pressure and temperature of a gas are related.
In the 18th century much of basic biology and chemistry was developed as part of the Age of Enlightenment.
The 19th century saw some of the great names of science: people like the chemist John Dalton, who developed the atomic theory of matter, Michael Faraday and James Maxwell who both put forward theories concerning electricity and magnetism, and Charles Darwin, who proposed the (still) controversial theory of evolution. Each of these developments forced scientists radically to re-examine their views of the way in which the world worked.
The last century brought discoveries such as relativity and quantum mechanics, which, again, required scientists to look at things in a completely different way. It makes you wonder what the iconoclastic discoveries of this century will be.
The table below, which is taken directly from The Open University course S103 Discovering Science, sets out the time-scale of some of the major events in Earth history and developments in science and technology. It shows something of the parallel development of human communication and of science and its technological applications, set in the context of Earth history as a whole.
The years before present (BP) shown in this table are, of course, approximate, in that they merely imply 'about that long ago'. As far as the older times are concerned, clearly no scientist could prove that the Earth was formed exactly 4 600 000 000 years ago, or that the first human settlements were established 12 000 years ago.
|Years BP||Events in Earth History|
|4 600 000 000||Earth and planets in the solar system formed|
|3 800 000 000||first evidence of life|
|440 000 000||evolution of first land plants|
|400 000 000||evolution of first land animals|
|3 000 000||evolution of first hominids (human-like creatures)|
|Developments in science and technology||Developments in communication|
|35 000||fluent human speech|
|12 000||first human settlements|
|9 000||use of stone tools|
|6 000||first primitive writing based on pictures (Egypt and Mesopotamia)|
|5 800||first use of bronze (alloy of tin and copper)|
|3 700||first alphabet developed (Palestine)|
|3 500||first use of iron|
|2 600||era of Greek science, based on philosophy (Aristotle, Pythagoras)|
|1 000||Chinese invented printing|
|700||experimental science of William of Occam|
|500||Earth orbits the Sun (Copernicus)||first printing press (Caxton)|
|400||circulation of blood (Harvey)|
|300||theory of gravity (Newton); invention of telescope|
|200||Industrial Revolution (in Britain)|
|150||Theory of evolution by natural selection (Darwin); early railways||photography invented|
|100||first powered flight; theory of special relativity (Einstein)||wireless telegraphy invented|
|50-60||first fully-electronic computer|
|40-50||structure of DNA (Watson and Crick); first human in Earth orbit (Gagarin)|
|30-40||first human on the moon (Armstrong)||computers with silicon chips|
|0-20||Human Genome Mapping Project; multiple organ transplants||lap-top computers; communications networking; the Internet; artificial intelligence|