Is it all predators or just pursuit and ambush style predators? They are the ones that really need depth perception. There must be a real cost to depth perception, so animals would have to have a need for it, even if they are not predators. Sharks have the lateral line senses, which is a lot better in the water then vision.
I don’t think there’s a hard rule you can put on it. Sharks are ambush predators, but they need a wide field of vision to scan above and below for prey. Monkeys are mostly herbivores or opportunistic omnivores, but they have forward facing eyes to jump through trees. It’s just about what they animal needs their eyes to do, and forward facing eyes are mostly used for trying to grab another animal.
Is it all predators or just pursuit and ambush style predators? They are the ones that really need depth perception. There must be a real cost to depth perception, so animals would have to have a need for it, even if they are not predators. Sharks have the lateral line senses, which is a lot better in the water then vision.
I don’t think there’s a hard rule you can put on it. Sharks are ambush predators, but they need a wide field of vision to scan above and below for prey. Monkeys are mostly herbivores or opportunistic omnivores, but they have forward facing eyes to jump through trees. It’s just about what they animal needs their eyes to do, and forward facing eyes are mostly used for trying to grab another animal.