Transcript: About six hundred million years ago in the oceans of the Earth the first multicelled organisms developed. These are distinct from colonies of simple cells like stromatolytes which existed much earlier. A multicelled organism is a large number of cells acting in concert within a single creature. In the evolution of life, the transition from prokaryotes to eukaryotes, cells with nuclei, spurred a huge amount of biological diversity. The transition from single-celled nuclei, eukaryotes, to multicelled organisms spurred an even larger amount of diversification. The diverse functions of cells led to specializations of their function. The cells were independent, and the organism was able to adapt better to the environment. The ceaseless experimentation of multicelled organisms lead to new capabilities. As just one example, consider the cells that evolved on the surface of a creature that were able to detect light. Eventually those cells could aggregate and form, over hundreds of millions of years, eyes.