Walking upright allowed habilis to start developing craftwork skills. Carpentry or stone sculpting requires very precise hand-to-eye co-ordination. Skills like these need well developed motor-neurone skills and sophisticated hand and finger co-ordination – processes that probably encouraged the evolution of bigger brains. Recent studies have shown that relative to other mammals, Homo habilis had a brain at least four times larger than it should have been for his size and weight.

Cooler temperatures tend to mean that less water evaporates from the seas, resulting in reduced rainfall in many inland areas. Such conditions gave birth to the great grasslands of today which replaced forested areas that need larger quantities of rainwater to sustain them. The prairies of North America, the pampas of Argentina and the grassland steppes of Europe and Central Asia all emerged during this Ice Age.

Morris Talansky, a US businessman, testified yesterday that he had handed over around $150,000 (£76,000) to Ehud Olmert, now Israeli Prime minister, over 15 years – including multithousand-dollar payments in envelopes stuffed with cash.

Ariel Sharon's son should go to jail for corruption next month, on the day the comatose former prime minister turns 80, Israel's Supreme Court ruled yesterday.

Britain's human rights record has been heavily criticised in an EU report which calls on the government to sign key international conventions before lecturing other nations on their failings.

A halt to four and a half years of bloody conflict was called yesterday by Israel and the new Palestinian leadership, as both sides pledged to seize what Ariel Sharon declared to be an opportunity for "security, tranquillity and peace" in the Middle East.