Humans have invented all kinds of weapons, but the bow and arrow have been used by tribes living in East Asia since the Paleolithic and in the Neolithic it had spread to hunting tribes all over the world. The Japanese yumiya, which gave birth to kyudo (Japanese Archery), is depicted on bronze vessels from the Stone Age, which already shows the long bow.
In Kyudo, two arrows are paired as one, and this is called one te. The two are each named haya (first arrow) and otoya (second arrow). Bird feathers are used for the arrow and the feathers look shiny and beautiful on the front and dull on the back. It is also symmetrical with the main shaft as the center, but if you look at the cross section it is not completely flat but slightly slanted toward the back. When attaching the feather, you tear the feather with the main shaft in the middle, but often you get surfaces that are slanted toward different sides. For one arrow you attach three feathers that are slanted in the same direction. You would get one arrow with the shiny side of the feathers pointing to your right side (outwards) and one arrow with the shiny side pointing to your left side (inside). The arrow with the shine on the right is the haya and the other one with the shine on the left is the otoya.
The haya is also called aniya (older brother arrow) and otoya is called ototoya (younger brother arrow). Thus the haya is shot first, followed by the otoya. The reason is that the haya has the beautiful, shiny side pointing outward, to the shooter’s right. The right side is where the kamiza (seat of honor). It is considered good courtesy to show the more beautiful arrow first, and thus the haya is shot first.
Since the haya’s surface is facing outward, it is slanted inward. This means that when the haya is shot is flies while spinning clockwise. The otoya spins anticlockwise as it flies. Because of the slant, the air resistance is different between the two sides. The shiny surface has less air resistance, thus creating the spin. This is the same reason a top stabilizes when spinning. This spin gives the arrow the gyro effect and enables the arrow to fly in a straight line. All peoples have been using some sort of bow and arrow, but almost all of them have bird feathers attached to their arrows. This seems to be some incredible ancient wisdom.
Since ancient times, the Japanese have used eagle and hawk feathers for their arrows. The feathers of the steller’s sea eagle, the golden eagle, the goshawk, the mountain hawk-eagle have all been treasured and used for arrows, as well as the feathers of the pheasant and the swan. In recent times, because of international regulations, turkey feathers have become the most popular.