Acommon visual behavior is the âhead jerk.â This motion is generally observedwhen an individual otter approaches a raft of sea otters. The approaching otternoses and sniffs the other otters while jerking its head from side to side.
Axis tilt is the vertical angle at which the ball rotates. Axis tilt is what is commonly known as spin. Axis tilt is determined by the position of the thumb during the release. If the hand turns too early, the thumb exits on top of the ball. Bowlers with a high degree of axis tilt will be able to see the top of their hand during the release and follow through.
The tilt of the Earth's spin axis with respect to the plane of its orbit about the sun (the ecliptic plane) is important for a habitable Earth. The Earth's spin axis is tilted 23.5Â° with respect to the ecliptic, giving moderate seasons and preventing temperature extremes anywhere on the planet. This illustration, patterned after Ward and Brownlee, summarizes the effects of different tilt angles with respect to the ecliptic plane.