What mysterious ways do animals experience touch beyond direct contact? How do creatures from wasps to elephants use touch to survive and thrive?
Ed Yong’s fascinating book An Immense World reveals how the sense of touch in animals extends far beyond what humans can imagine. From detecting vibrations in the ground to sensing distortions in water, animals use remarkable methods to perceive their environment and connect with others.
Keep reading to discover the extraordinary touch abilities that help creatures navigate their world, find food, escape danger, and build relationships.
The Sense of Touch in Animals
Humans primarily touch with their hands. The sense of touch in animals works differently, as they use other body parts and methods. This includes methods that sense from afar, without the need for direct contact. Yong explains that animals can touch by sensing currents, flow, and vibrations in water, air, and soil. Here are a few ways they do this.
1) Some animals use distortions in their environment. For example, the red knot, a type of shorebird, can detect clams buried deep in the sand by using its bill to create a pressure wave of water that distorts if it hits something hard. The bird uses touch sensors on its bill to feel those distortions, allowing it to touch remotely.
Another example is harbor seals, which hunt fish using touch sensors on their whiskers that can feel the invisible wake left by fish as they swim. Fish also use sensors on their bodies to detect distortions in the water they’re displacing as they swim, allowing them to sense their surroundings in all directions so they can detect predators, prey, and their own kind (this is why they’re able to swim in schools).
2) Others use vibrations to touch. Yong says tree frog embryos can feel the vibrations of a snake chewing on their egg cases, which causes them to hatch (and, hopefully, escape!). They can distinguish these snake vibrations from other vibrations, such as those caused by rain and wind. Meanwhile, elephants can feel seismic vibrations in the ground with their feet, allowing them to sense the presence of not-yet-visible predators or other elephants.
3) Some species have specialized body parts to touch. The emerald jewel wasp kills cockroaches by stinging them in the brain, turning them into zombies that the wasps can lead by the antennae to their lair to act as a nest and food for their young. The wasp is able to do this because its stinger is sensitive to touch and can feel the roach’s brain inside its body.
| The Social Purpose of Touch In addition to using various forms of touch to detect prey and predators, animals—including humans—use physical touch as a means of deepening social bonds and promoting emotional and physical health. Research demonstrates that primates such as rhesus monkeys and chimpanzees groom each other not only for hygiene purposes, but also to decrease stress and aggression (female chimpanzees break up fights between males by grooming first one, then the other) and to garner social favors (a chimp is more likely to share food with another chimp that’s previously groomed it). In humans, studies show that romantic partners are more likely to report higher levels of relationship trust and satisfaction the more they engage in “grooming” behaviors, such as wiping away the other’s tears or running their hands through the other’s hair. In addition, both animal and human babies require physical touch for development and even survival. Studies of rats and monkeys demonstrate that babies taken from their mothers experience anxiety, depression, and, in the case of rats, a weakened immune system. Research also shows that premature human babies, who have an increased risk of death in their first few weeks, are 51% less likely to die if they’re given “kangaroo care,” which consists of a parent repeatedly holding their baby against their bare chest for extended periods. |
