What we don’t know

125 questions still unsolved

Happy Birthday, Science! The famous US-journal celebrates its 125th anniversary with a special issue dedicated to 125 great unsolved scientific mysteries of our time. Rather than a comprehensive inventory, this list is a significant sampling of the major questions facing science today.

Founded by Thomas A. Edison, Science debuted on July 3rd 1880, with 12 pages of articles on the possibility of electric-powered railroads, the latest observations of the Pleiades and advice to science teachers on the importance of studying animal brains. Issues over the following decades included articles by Albert Einstein, Edwin Hubble, Louis Leakey and other great scientific thinkers. Today, Science's correspondents based around the world file stories on their laptops.

Among these 125 questions Science's editors have identified are the following examples:

• What is the universe made of?

In the last few decades, cosmologists have discovered that the ordinary matter that makes up stars and galaxies is less than 5 percent of everything there is. What is the nature of the „dark“ matter that makes up the rest?

• What is the biological basis of consciousness?

In contrast to René Descartes' 17thcentury declaration that the mind and body are entirely separate, a new view is that whatever happens in the mind arises from a process in the brain. But scientists are only just beginning to unravel those processes.

• Why do humans have so few genes?

To biologists' great surprise, once the human genome was sequenced in the late 1990s, it became clear that we only have about 25,000 genes – about the same numbers as the flowering plant Arabidopsis. The details of how those genes are regulated and expressed is a central question in biology.

• How much can human life span be extended?

Studies of long-lived mice and worms have convinced some scientists that human aging can be slowed, perhaps allowing many of us to live beyond 100, but others think our life spans are more fixed.

• Will Malthus continue to be wrong?

In 1798, Thomas Malthus argued that human population growth will inevitably be checked, for example by famine, war or disease. Two centuries later, the world's population has risen sixfold, without the largescale collapses that Malthus had predicted. Can we continue to avoid catastrophe by shifting to more sustainable patterns of consumption and development?

• What controls organ regeneration?
• How can a skin cell become a nerve cell?
• How does earth’s interior work?
• …

Questions like these show us that there is still plenty of room for discoveries in the future. Further information: www.sciencemag.org

Vocabulary

issue Ausgabe
to dedicate widmen
comprehensive umfassend
inventory Bestandsaufnahme
to debut zum ersten Mal auftreten, debütieren
to file ablegen, abheften
matter Stoff, Materie
consciousness Bewusstsein
to unravel enträtseln
span Spanne
famine Hungersnot
sixfold sechsfach
sustainable nachhaltig

Heftnummer: 2005/03
Autor: Paeschke, Alexa