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HORSES
From page 25
No one knows for sure how far horses can see, mainly because such tests are impossible to do accurately. Horses see primarily by monocular vision, meaning that they see different things out of each eye. Horses have a wide monocular( panoramic) view of the horizon and can see about 340-360 ° around it. Binocular vision( seeing the same out of both eyes) is used on a limited basis and primarily when the horse is looking straight ahead. Having binocular vision in
front of 60-70 ° means the horse needs to move the head to see where it is going. It can only focus fully for a short distance ahead- about 2m. This is a problem in jumping- it focuses then must remember and trust it ' s memory of the object. As the eyes are on the sides of its head, the horse does not normally see objects in depth. It sees them like we do with one eye closed. It sees them with less detail than humans but is more sensitive to movement. Blinkers, therefore considerably dull a horse ' s visual sense and limit its ability greatly. Eyes are perfectly placed for cropping pasture, which it does for half its life, so the horse ' s visual area is more towards the ground than the sky. The horse can raise its head quickly and focus on objects at various distances away
Horses have a well-developed sense of smell. from it. A horse ' s vision is its primary detector of danger. Colour vision is still debated. Some work shows the horse can see colour starting from yellow, green, blue and red in that order. Nevertheless, the bright colours used to paint showjumping obstacles are more likely to startle the
Horses’ ears rotate, and flatten, to attenuate their hearing rider than the horse, which will see less of the colour and more of the light-and-dark contrast between the colours used. A horse needs time to adjust its vision between light and dark, which becomes a consideration when expecting a horse to enter a dark horsebox on a bright, sunny day.( Hint: Never paint the inside walls of your box in a dark colour or obscure the windows, and turn the box so that the sun is behind the open box when loading to maximise the light flooding the interior.) The horse has a blind spot behind its head which increases when the head is lifted. Soitisimportantto allow the horse to move its head to see objects in its way. Horses are generally reluctant to enter dark enclosures but quieten down when in there and feel safe looking out into the light. Horses are often blindfolded to quieten them. Don ' t look a strange horse in the eye. It ' s a threatening pose. A horse will habitu-
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