To have arrived on this earth as a product of a biological accident, only to depart through human arrogance, would be the ultimate irony.

The greatest problem we face is the growing number of people living in poverty. The related sense of hopelessness has to be impacting on every part of environmental management.

Sadly, I am not able to take part in the fieldwork myself so much anymore, as both of my legs were amputated following an airplane crash twelve years ago.

It occurred to me that if I did not handle the crash correctly, there would be no survivors.

Echoing the criticism made of his father's habilis skulls, he added that Lucy's skull was so incomplete that most of it was 'imagination made of plaster of Paris', thus making it impossible to draw any firm conclusion about what species she belonged to.

It has taken biologists some 230 years to identify and describe three quarters of a million insects; if there are indeed at least thirty million, as Erwin (Terry Erwin, the Smithsonian Institute) estimates, then, working as they have in the past, insect taxonomists have ten thousand years of employment ahead of them. Ghilean Prance, director of the Botanical Gardens in Kew, estimates that a complete list of plants in the Americas would occupy taxonomists for four centuries, again working at historical rates.

The whole story is about change. We are very lucky that the earth's history is recorded in fossilized remains. And we can see the changes. Unfortunately, there will always be gaps in our knowledge, but there is no doubt that we and everything living today has evolved.