Many fish use electric signals

Press, 8 September 1982, Page 22

Many fish use electric signals

Electric communication in fish is one item in this week's “8.8. C. Science Magazine” (Concert programme, 7.30 tonight). A few fish are able to produce large electric discharges to stun their prey. Recent work has shown, however, that a great many fish make use of lower-powered electric signals for communication and navigation. Studies of these signals show some remarkably sophisticated developments enabling fish to distinguish between species, individuals and sexes. The programme will look at how some of these systems are used. The other subjects discussed in “8.8. C. Science Magazine” will be research into a new possible treatment for some types of cancer using a group of chemicals called porphyrins which form an essential constituent of the blood; and the value to solar astronomers of total eclipses as an aid to our understanding of the Sun.Total solar eclipses are infrequent, but one is due to cross the Indian Ocean and the South Pacific next year. Law of Sea

The Law of the Sea has been adopted at the United Nations, and will come into force when it has been ratified by 60 nations. The hope is that the treaty will bring order to mining minerals on the ocean bed, the extent of territorial waters, countries’ precise rights over their coastal water and continental shelves, fishing and marine conservation and the freedom of ships to pass through narrow straits. The United States voted against it and industrial countries like West Germany, Britain and the Soviet Union abstained. The 8.8. C. asks in a “Your World” programme (Concert programme, 8.40 tonight), "What will the law mean?”