When two animals communicate, one animal, called the sender, produces a change in the behavior of a second animal, the receiver. Behavioral ecologists believe that communication behaviors evolve because the fitness of the sender is increased by the effect the message has on the receiver.

Animals communicate by four main mechanisms: sight, sound, touch, and chemical signaling..

The methods used by a particular animal largely depend on the animal’s environment. Most land animals that are active in the daylight hours, like these birds, have good eyesight and hearing, so much of their communication uses sight and sound. Animals that are active at night, like bats, or animals that live in environments where visibility is reduced, often communicate using touch and sound. Whales and dolphins live in seawater with reduced visibility, so sound is important to these creatures.

Simpler animals, like flatworms, can absorb chemicals directly through their outer covering; they use chemical signaling extensively.

Visual communication is important to most vertebrates, including humans. Wolves and dogs use visual behaviors, such as lowering their tails and lying on their backs to show submission. This kind of visual communication is called a display.

Another kind of visual communication is called a badge. A badge involves appearance, such as the showiness manifested by the members of one sex of a species. A striking example is the male peacock.

Animals use sounds, or auditory communication, to convey such things as danger, readiness to reproduce, and species recognition. Whales, like this humpback, use low frequencies to communicate through water for distances of more than one hundred miles.

Land-dwelling animals also use sound to communicate. The rich songs of many bird species communicate everything from warnings and marking of territories to finding mates.

Although all primates use vocal communication to some extent, no animal seems to rival the complexity and informational content of human speech.

Touching, or tactile communication, is also a common way for animals to communicate. It is used in social bonding, infant care, grooming, and mating.

Monkeys and apes pick bugs out of each other's fur as part of grooming and as a display of affection.

Several methods of communication are used during the bee dances, first described by the zoologist Karl von Frisch in the early 1900s. He found that bees use two types of dances to provide information about the location and direction of food to others in the hive. This round dance is a circular pattern when food is nearby. The waggle dance, a figure eight pattern, communicates that food is farther away.

The bees use a variety of communication methods during their dance. They vibrate their wings, they regurgitate some of the nectar from the food source, and they waggle their abdomens from side to side.

Chemicals can cause behavioral reactions when smelled or eaten. Special chemical signaling compounds called pheromones are used in communication between animals of the same species.

Ants secrete a pheromone to guide other ants to food by leaving a marked trail behind them.

Releaser pheromones, like the ant pheromone, trigger immediate behaviors.

Other pheromones, called primer pheromones, cause physiological changes.

Queen bees, ants, and termites secrete primer pheromones that their workers eat. The chemical prevents the workers from developing to reproductive maturity. In fact, the workers are actually sexually underdeveloped females.

Let’s see if you can identify the types of communication used in the examples shown here.

Drag the label for each behavior onto the appropriate picture. Then click Submit

Correct Answer: That’s right!

Incorrect Answer: That’s not quite right.

All: The howling wolf is an example of auditory communication. The stickleback’s behavior consists of a visual display, and is an example of visual communication. The skunk signals by spraying – this is chemical signaling. Finally, the subordinate fox licks the dominant fox’s face in a gesture of submission – this is tactile communication.

Now that we’ve seen the different communication methods animals use, let’s look at how some of them are used during mating: one of the most important social interactions of animals.

Copyright 2006 The Regents of the University of California and Monterey Institute for Technology and Education