What is man's single greatest achievement?

One opinion: the discovery of time

Man's single greatest achievement is the discovery of time. With out this discovery agriculture would not have flourished as it has, and our ability to navigate space ships or in and out of the Earth's orbit would be non-existent. It is our discovery of time and our understanding of orbital variations that has and will continue to mark the upward surge of mankind.

Our greatest achievement is our ability to come together as a group, as a community, and as a society. Civilization and all significant human achievements would not have been possible otherwise. The passing and exchanging of knowledge is a function of our ability to work together. The accrued knowledge accumulated from the achievements of pass generations made all modern achievements possible.

1961, first man in space, marking the first time any natural creature that we know of has left the biOSphere and 1969 with the moon landing. Signifying the first creatures in the history of earth to settle a different planetoid. Not only leaving their natural environment but leaving the planet upon which they evolved is in my opinion our greatest achievement.

5, July 1996 Dolly the Sheep is cloned with success, living a long healthy life. With the ability to clone, man has reached a level of technology that allows the creation of life though a none natural process. In a sense the only other creature known to have this ability is that of a god or God.