In 1202, an Italian mathematician, best known as Fibonacci, proposed the following problem:
- A pair of young rabbits takes a month to reach maturity
- Once mature, it will produce one other pair of rabbits each month
- How many pairs of rabbits will we have at the end of one year?
Table 1 below illustrates the development of the rabbit population in the first 6 months. The small rabbit pairs are ones that are less than a month old. We can see that, in February, we have the same original pair. It has simply matured and will produce a new pair in March. If we examine the pairs in May, we find that we have:
- The three pairs from April; and
- Two new pairs, since we had two mature pairs in April
| Month | Num of pairs of rabbits |
| Jan | 1 |
| Feb | 1 |
| Mar | 2 |
| Apr | 3 |
| May | 5 |
| Jun | 8 |
As a general rule, each month’s population will be:
- The previous month’s population, plus
- The new rabbits, produced by the mature pairs. Rabbits are mature only if they were present two months ago.
To illustrate this formula, take a table 2 below. The first two months have one pair in each of them. After that, you can obtain the number of pairs in each subsequent month by adding up the numbers from the last two months.
Let’s take, by way of an example, the calculation for month 10:
Continuing in this way, the answer to our problem is: 144 pairs of rabbits will be present at the end of one year.
The Fibonacci sequence
The Fibonacci sequence is a never ending sequence of numbers. Basically, we extend table 2 above by always adding the last two numbers in the table. The numbers that make up the sequence are known as Fibonacci numbers.
I highly recommend that you watch the following video, Spirals, Fibonacci and being a plant. In it, you will see fascinating occurrences of the Fibonacci numbers in nature.
Fib poetry
Fib Poetry is an attempt at emulating Haiku: A poem with a strict structure. In Fib Poetry, the number of syllables on each line follows the Fibonacci Sequence. Here is an attempt at writing a Fib Poem:
Two
Young
Fo-xes
Run, run fast
They spot a chick-en
And they de-cide to let it go!
If you have any observations or comments, please leave a comment.
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