1, the law of new branches sprouting.

The growth of trees, because of the appearance of new branches, often needs a "rest" time to grow itself, and then it can sprout new branches. Therefore, a tree seedling will grow a new branch after a certain interval, such as one year; In the second year, the new branches "rested" and the old branches were still sprouting; Since then, the old branches germinate at the same time as the branches that have been "rested" for one year, and the new branches that were born that year are "rested" in the second year. In this way, the number of branches of a tree every year constitutes Fibonacci series. This law is the famous "Rudvig's Law" in biology.

2. The secret of the number of petals

By observing the petals of Trillium, Rosa davurica, Sanguisorba americana, cosmos, Jin Fenghua, aquilegia, lily and iris, we can find that their petals all have Fibonacci numbers: 3, 5, 8, 13, 2 1, ...

Among them, lily has 3 petals, plum blossom has 5 petals, delphinium has 8 petals, marigold 13 petals, sunflower has 2 petals1or 34 petals, and daisy has 34 petals, 55 petals and 89 petals.

Fibonacci spiral: 13 spiral rotates clockwise, and 2 1 spiral rotates counterclockwise.

The Fibonacci spiral formed by sunflower seeds can sometimes reach 89 or even 144.

Cause analysis: This seems to be the "best way" for plants to arrange their seeds. It can make all seeds have the same size but proper density, so as not to squeeze too many seeds at the center of the circle and be sparse at the circumference.

3. Arrangement of leaves, branches and stems of plants

The leaves from one position to the next are called a cycle. The number of times a leaf rotates in a cycle is also Fibonacci number. The ratio of the number of leaves to the number of leaves rotating in a period is called leaf order (for example, most leaf order ratios are shown as Fibonacci series).

4. Rabbit reproduction

Generally speaking, rabbits can reproduce two months after birth, and a pair of rabbits can give birth to a pair of rabbits every month. If all rabbits don't die, how many pairs of rabbits can you breed in a year?

5. The way to climb stairs

There is a flight of stairs with 10 steps, and it is stipulated that each step can only span one or two steps. How many different ways are there to climb 10 steps?

This is a Fibonacci sequence: there is a way to climb the first step; There are two ways to climb two steps; There are three ways to climb three steps; There are five ways to climb the fourth step ... 1, 2, 3, 5, 8, 13 ... So there are 89 ways to climb the tenth step.

6. Other Fibonacci series

The arrangement of pinecones, pineapples and leaves, the number of petals of some flowers (typically sunflower petals), beehives, dragonfly wings, transcendental number E (more can be deduced), golden rectangle, golden section, equiangular spiral, twelve-average law, etc.

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9. The way leaves grow

For many plants, every leaf grows near the central axis. In order to make the best use of space (considering that leaves are long one by one, not at the same time), the included angle between each leaf and the previous leaf should be 222.5 degrees, which is called the "golden angle" because its ratio to the whole circumference of 360 degrees is the golden section number of 0.6 1800.