Why do sharks not bite divers who are right next to them?
In: Biology
Humans are relatively new creatures from the shark’s perspective. Sharks have been living on this planet (450 million years) for about 1500 times longer than humans have (300,000 years). Human’s appearance on the planet is but a tiny blip on the evolutionary timeline relative to other organisms.
Virtually all living things are concerned with only a few criteria: Can we survive in this surrounding environment? How difficult will that survival be in the longterm?
For the majority of a large shark’s existence, the answers to those questions have been “Yes” and “Not difficult at all” (until we arrived, of course)
To be more specific, a shark’s survival depends generally on how easy it can acquire food and how easy it can evade very particular circumstances that result in the shark either getting trapped to the point it cannot move, or being killed by the very few existing apex predators ABOVE sharks in the food chain (by us for example).
Survival is the absolute top priority to virtually all living things on the planet. That survival, from a large shark’s perspective, involves being very cautious when approached by other living things that are either new to them or appear to have a potential to cause harm to them. When that living thing approaching the shark is us humans, most sharks will likely behave like the previous statement. Sharks will only bite or attack humans if they are near death starving (not likely since they are an apex predator of the ocean) OR if their survival feels threatened by the human in that moment.
Us humans are most certainly not on a great white shark’s typical food menu like seals are. This assertion has many evidences for confirmation such as, surfers who are bitten very badly by a great white shark but still survive because the shark 1. Thought the surfer paddling on the board was a seal (a seal and a paddling surfer look almost identical from the perspective of the shark beneath) and 2. The shark swam away immediately when it realized it had bitten something that most certainly was not a seal.
The majority of other shark-human conflicts are going to be territorial. This again, however, has a direct relationship with the thought of being threatened.
One last bit of information worthy of note regarding great whites is that they rely on the smell of blood in the water to search for food. They have an incomprehensible sense for blood (in terms of blood to water ratio by volume). A great white shark will thus instinctually be activated (aggression-wise) at the smell of blood. Assuming that human divers are not cut or bleeding underwater when near a great white shark, the degree to which the shark becomes aggressive will be less.
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