The human brain isn't used to dealing with numbers which are either extremely large or extremely small. But those are exactly the types of numbers you encounter in science. In Astronomy, the distances between stars and galaxies are unimaginable. In the evolution of life, the time that has elapsed since life first started on Earth is unbelievable. In genetics, the size of the cells, of the chromosomes within them and of the DNA bases within those chromosomes are incredibly small. So, here are some facts and figures way outside the everyday experience of human life. I hope that they will inspire you to want to find out more.

WARNING! Some of these statistics may blow your mind.


The Universe

Life on Earth

Scientists keep changing their mind about when life first started on Earth. And each time they change their minds they push the date further and further back. Current estimates put the origin of life on earth at between three and four thousand million years ago.

For the first two thousand million years, life consisted of nothing more than single cells in the proverbial primeval swamp.

The DNA "book" which makes up a human being has three thousand million letters, all combinations of four bases, called A, C, G and T. This "book" exists in every single cell of the human body. Scientists are in the process of recording this "book" so that it can be read.

If all the DNA in all the cells in a single human being were stretched out, it would reach to the moon and back eight times.

There are thought to be 30,000,000 different species on Earth.

It has been estimated that the species which exist today constitute only 1% of all the species that have ever existed.

Every cell in your body contains the equivalent of 46 immense data tapes reeling off digital characters via numerous reading heads working simultaneously.

Genes are pure information -- information that can be encoded, recoded and decoded, without any degradation or change of meaning...Since it is digital copying the fidelity of the copying can be immense. They are copied down the generations with just enough occasional errors to introduce variety.

Science links


Hubble Telescope. Here you can see the latest photos sent back from the Hubble Telescope out in space.
Astronomy Picture of the Day
The Solar System. A guide to the planets.

Genetics and evolution

Richard Dawkins. This was an unofficial site which promoted the books, writings, and activities of one of today's most outspoken, and often humorous, scientists. It now operates as an archive of speeches and articles by Dawkins up to 2001.

General Science

Planet Science, the award-winning site of New Scientist magazine. You have to register but it is free.
The Why Files, a very chatty US site which gives you the background on science stories which are in the news.

And some books......

"River Out of Eden", "The Blind Watchmaker" "Climbing Mount Improbable" and "The Selfish Gene" by Richard Dawkins.
"The Language of Genes" by Steve Jones.
"In Search of the Big Bang", "In Search of the Double Helix" and "In Search of Schrodinger's Cat" (about Quantum Physics) by John Gribbin.
"The Origin of Humankind" by Richard Leakey
"Life -- an unauthorised biography (a natural history of the first four billion years of life on earth)" by Richard Fortey.

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