I. In 1859, scientists believed that the cell (the basic unit of life) was a simple, jelly-like mass. If the cell was simple, then the possibility that life could have evolved incrementally appeared feasible.
II. Today powerful technologies have revealed that the cell is actually a world of spectacular complexityfilled with machinery made of molecules.
III. The bacterial flagellum.
In the 19th Century scientists thought that the cell was a simple glob of protoplasm that was not hard to explain.
During the last half century our knowledge about the cell has increased dramatically.
Each cell is packed with circuits, assembly instructions, and miniature machines, the complexity of which, Charles Darwin could never have imagined.
The bacterial flagellar motor becomes visible when magnified 50,000 times through an electron micrograph.
Howard Berg, a Harvard professor, has called the bacterial flagellar motor the most efficient machine in the universe.
- Molecular Machines
- Bacterial Flagellum
“If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous successive slight modifications, my theory would absolutely break down.”
“Natural selection acts only by taking advantage of slight successive variations. She can never take a great and sudden leap, but must advance by short and sure, though slow steps.”