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PASSAGE 1

Animal Communication

Scientists have identified several distinct forms of communication animals use to either
send or receive information in their environments. These methods of communication
inherent to various animals are genetic adaptations to specific environments, providing
animals with necessary tools for survival and perpetuation of their species.
Electro-communication, the ability to produce and receive electric signals, is a method
of communication used by some aquatic species for courtship, and marking territorial
boundaries, as well as a means of aggression and defense. Several species of fish are
known for possessing an electric organ that gives them the ability to create electric
fields and receive electric signals by the means of electro receptors located throughout
their bodies. One of the most well-known examples is the electric eel, which is able to
stun its predators and prey by generating electric shocks that may contain up to several
hundred volts of electricity.

Another unique form of animal communication is referred to as thermal communication.
Some species have the ability to sense infrared radiation which allows them to detect
prey even in total darkness. Although this physiological adaptation is most commonly
seen in serpents such as rattlesnakes, boas and pythons, other types of animals are
also found to possess this ability including several species of beetles, vampire bats
and bed bugs. In the case of snakes, heat-sensitive pit organs in their face can detect
and respond to the slightest thermal fluctuation in the environment, allowing them to
accurately measure the distance of the heat source.  Some snakes are even known to
detect potential prey at a distance of about one meter and use their facial pit organs for
orienting and striking towards it.
 Seismic communication refers to the ability to detect vibrations emitted in a particular
environment. Elephants demonstrate this ability through the strong rumbling sounds
they produce, which are not only transmitted through the air, but also through the
ground. A Other elephants are able to pick up these rumbling sounds in the ground and
discern the location of elephants producing the vibrations. B Studies have also shown
that elephants can respond to seismic vibrations created by their environment. C
Elephants are able to follow seismic vibrations to an area of rainfall when they search
for water. D

Echolocation is the ability of an animal to send out sound waves which hit objects and
then bounce back as vibrations to the animal. Consequently, these allow animals to
identify where objects are located in their surroundings. Bats, toothed-whales and
dolphins have all shown the ability to use echolocation. In the case of dolphins, they
produce high-frequency clicks to echolocate objects nearby. In addition to determining
the shape and size of an object, this ability allows dolphins to determine the speed,

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