MANY years ago at the foot of a forest-covered hill was a small town, and just above the town on the hillside was a little house in which lived an old woman and her grandson.
The old woman, who was very industrious, earned their living by removing the seeds from cotton, and she always had near at hand a basket in which were cotton and a long stick that she used for a spindle. The boy was lazy and would not do anything to help his grandmother, but every day went down to the town and gambled.
One day, when he had been losing money, the boy went home and was cross because his supper was not ready.
"I am hurrying to get the seeds out of this cotton," said the grandmother, "and as soon as I sell it, I will buy us some food."
At this the boy fell into a rage, and he picked up some cocoanut shells and threw them at his grandmother. Then she became angry and began to whip him with her spindle, when suddenly he was changed into an ugly animal, and the cotton became hair which covered his body, while the stick itself became his tail.
As soon as the boy found that he had become an ugly creature he ran down into the town and began whipping his companions, the gamblers, with his tail, and immediately they were turned into animals like himself.
Then the people would no longer have them in the town, but drove them out. They went to the forest where they lived in the trees, and ever since they have been known as monkeys. 
Mabel Cook. Philippine Folk Tales. London:
 Here we have an old
type of tale explaining where monkeys came from. See note 2, p. 130. (Referenced
note states: "Monkeys are numerous throughout the Philippines, and
it is doubtless their human appearance and actions that have caused the
different tribes to try to account for their origin from man. Here we
have the most likely way that the Bukidnon can see for their coming.")