Many historical and contemporary sources claim that the golden ratio is rather ubiquitous in nature. Some examples are:
The growth pattern of leaves;
The geometrical surfaces of some vegetables and shells;
The proportions of the bones of some animals.
However, while we can't deny the presence of geometrical patterns in nature, we can't confirm the exactness of the proportions of the examples above: some present huge variations, while others only approximate the golden ratio. Read more