This story is a myth from the Mandaya tribe of Mindanao, Philippines.
In the very early days before there were any people on the earth, the limokon (a kind of dove ) were very powerful and could talk like men though they looked like birds. One limokon laid two eggs, one at the mouth of the Mayo River and one farther up its course. After some time these eggs hatched, and the one at the mouth of the river became a man, while the other became a woman.
The man lived alone on the bank of the river for a long time, but he was very lonely and wished many times for a companion. One day when he was crossing the river something was swept against his legs with such force that it nearly caused him to drown. On examining it, he found that it was a hair, and he determined to go up the river and find whence it came. He traveled up the stream, looking on both banks, until finally he found the woman, and he was very happy to think that at last he could have a companion.
They were married and had many children, who are the Mandaya still living along the Mayo River.
Source: Mabel Cook Cole, Philippine Folk Tales (Chicago: A. C. McClurg and Company, 1916), pp. 143-144.
Notes by Mabel Cook Cole:
This origin story is of a very different type from those of the Bukidnon and Bagobo. While the others show foreign influence, this appears to be typically primitive.
The limokon is the omen bird of the Mandaya. It is believed to be a messenger from the spirit world which, by its calls, warns the people of danger or promises them success. If the coo of this bird comes from the right side, it is a good sign, but if it is on the left, in back, or in front, it is a bad sign, and the Mandaya knows that he must change his plans.