I believe that the race from the moon which was technologically advanced created the devil fruits and the Gomu Gomu no mi was the first one.
It was consumed by the person who goes on to become the figure around which the legend of Nika started and through the power of rubber which can be synonymous with freedom in the one piece world, have lead to the spawning of other fruits
It was consumed by the person who goes on to become the figure around which the legend of Nika started and through the power of rubber which can be synonymous with freedom in the one piece world, have lead to the spawning of other fruits