Animals That Employ Spitting for Defense
Many animals use spitting as a defensive tactic. This behavior involves expelling irritating, disorienting, or unpleasant substances to deter threats.
Spitting cobras are well-known for their ability to accurately spray venom at an aggressor’s eyes. These snakes can eject venom up to several meters, aiming for the sensitive mucous membranes of an attacker. The venom, while not typically lethal when sprayed, causes immediate and intense pain, inflammation, and temporary blindness, allowing the cobra to escape.
Llamas and camels employ a less toxic but effective defensive spit. When threatened, they regurgitate foul-smelling, partially digested stomach contents and project them at the perceived threat. This projectile is not harmful but is highly unpleasant due to its odor and texture, serving as a strong deterrent.
Bombardier beetles utilize a remarkable chemical spray for defense, which can be considered a form of spitting. These beetles possess two separate glands in their abdomen that store hydroquinone and hydrogen peroxide. When threatened, these chemicals are mixed in a reaction chamber with enzymes, producing a boiling, noxious, and irritating spray that can be accurately aimed at attackers.
Animals That Spit to Hunt
Beyond defense, some animals use spitting as a precise hunting strategy. This offensive use often involves dislodging or incapacitating prey from a distance.
The archerfish is a prime example of an animal that spits to hunt, targeting insects above the water’s surface. These fish position themselves strategically beneath overhanging vegetation, observing their prey. They then shoot a powerful, precise stream of water, knocking the insect into the water for consumption. They adjust the force and direction of their shot based on the distance and angle to the prey, demonstrating sophisticated hydrodynamics. This unique technique allows them to access food sources unavailable to many other aquatic predators.
The Science of Animal Spitting
Spitting in the animal kingdom involves various biological and physical mechanisms. The expelled substances vary widely, from toxic venom to water or regurgitated food.
Venom spitting in cobras relies on specialized fangs that have small, forward-facing orifices at their tips. Muscles surrounding the venom glands contract rapidly, forcing the venom through these openings under high pressure. The cobra’s ability to aim precisely involves complex muscular control of the head and neck, allowing them to track and target moving threats.
The projectile spitting of llamas and camels involves the rapid expulsion of stomach contents through their mouths. This action is driven by strong muscular contractions of the stomach and esophagus, combined with a sudden opening of the mouth. The unpleasant nature of the expelled material, rather than its force, is the primary deterrent.
Archerfish use a unique combination of oral structures and muscular force to create their powerful water jets. They rapidly compress their opercula (gill covers) and mouth, forcing water through a narrow groove on the roof of their mouth. The shape of this groove and the rapid muscular contraction create a focused, high-velocity stream that can overcome surface tension and gravity to reach their aerial targets.