Spira mirabilis, Latin for miraculous spiral, is another name for the logarithmic spiral. Although this curve had already been named by other mathematicians, the specific name (miraculous or marvelous spiral) was given to this curve by Jacob Bernoulli, because he was fascinated by one of its unique mathematical properties: the size of the spiral increases but its shape is unaltered with each successive curve, a property known as self-similarity. Possibly as a result of this unique property, the spira mirabilis has evolved in nature, appearing in certain growing forms such as shells and sunflower heads.
Sunset 11/12/16 ~ Normacot Overbridge, Longton, Stoke on Trent
Balanced Rocks at Andicuri Beach, Northern Aruba
The term 'protea' is used to cover a range of related plants in addition to the genus Protea, including Leucospermum and Leucadendron.. They are native to South Africa.
