Dr. Reem Alajmi Presented by: Insect communication Dr. Reem Alajmi Presented by:

Contents Introduction Types of insect communication - Visual communication. - Chemical communication. - Tactile communication. - Acoustic communication. - References: The principles of Insect Physiology. The insects structure and function. Internet.

Introduction Communication: It is the exchange of information between individuals Most insect language is innate. And most of their language is inherited, so each individual born with a distinctive vocabulary that shared only with other members of its own species. Insects may send a communication signals by: 1- Doing something (e.g. make a noise, release a chemical or flash a light). 2- By physical makeup (e.g. wing pattern, body colour)

Why insects communicate? 1- Recognition of kin or nest mates. 2- Locating or identifying a member of the opposite sex. 3- Facilitation of courtship and mating. 4- Giving directions for location of food. 5- Regulating spatial distribution of individuals, aggregation or dispersal; establishing and maintaining a territory. 6- Warning of danger; setting off an alarm. 7- Expressing threat or submission. 8- mimicry.

-Like other animals, insects use their five senses to acquire information about their environment (taste, touch, vision, hearing, olfaction (smell)). So insect communicate by:

Visual Communication

Some insects use bright colours, eyespots or other The colour patterns and other markings of the wings (butterflies and moths) facilitate species recognition (like football players). Some insects use bright colours, eyespots or other distinctive patterns to scare a way predators. used in courtship dialogue between a male (usually flying) and a female (usually perched in the vegetation). Each species has a unique flash pattern and response time. For example, Males of Photinus pyralis emit a signal J shape flash during a rising flight movement and the female responds with a single flash after a tow second intervals. However, the male of Photinus consumilis emit a series of 3.5 short flashes and a female respond after a double flash. E.g. Fire flies pulses of light are used in courtship dialogue between a male (usually flying) and a female (usually perched in the vegetation). Each species has a unique flash pattern and response time. For example, Males of Photinus pyralis emit a signal J shape flash during a rising flight movement and the female responds with a single flash after a tow second intervals. However, the male of Photinus consumilis emit a series of 3.5 short flashes and a female respond after a double flash.

Some insect use dance-like body movements to attract a mate or to communicate with nest mate. Most visual communicate are effective during daylight, but some insect can generate their own light and use visual signals that can be seen at night.

Fire flies pulses of light are used in courtship dialogue between a male (usually flying) and a female (usually perched in the vegetation). Each species has a unique flash pattern and response time.

Males of Photinus pyralis emit a signal J shape flash during a rising flight movement and the female responds with a single flash after a tow second intervals. However, the male of Photinus consumilis emit a series of 3.5 short flashes and a female respond after a double flash.

Some insect can communicate using wavelength in the ultraviolet light. female cabbage butterflies have an ultraviolet reflecting scales on the dorsal wing surface, when they fly, each down stroke of the wing create a brief flash U.V. that male recognize them for mating.

In alfalfa butterflies, males have U. V In alfalfa butterflies, males have U.V. reflective scales and missing scales is a sign for male ageing.

Chemical communication

It is the most common way of insect communication. These chemicals are divided into 2 groups. 1- Phermons: Chemical signals that carry information from one individual to another member of the same species. These includes sex attractants, alarm substance and many other intraspecific messages. 2- Allelochemicals: chemical signals that travel between individual of different species. These includes defensive signals such as repellents, compounds used to locate suitable host plant, and other signals to regulate interspecific behaviours.

Functions of Phermones: -Phermones communications found in 1600 insects species. Functions of Phermones: 1- Queen bee emit phermones that affects the development of workers bee. 2- Ant use phermones to recruit nest mates to a food source.

3- When laying their eggs, some flies moths and beetles use certain phermones to repel insects of the same and competing species, thereby protecting their progeny.

4- Aphids give alarm phermones that urge neighbouring aphids to flee from nearby predators.

5- Many insect females use phermones to attract male for mating. 6- Some male moths use phermones to entice female to mate with them. Scorpionflies male attack female by mating pheromone

some common exocrine glands that occur in ants Currently, over 70 distinct exocrine glands can be distinguished in the social insects (at least 45 in ants, 21 in bees, 14 in wasps and 11 in termites).

Chemicals can be known by tasting or smelling by insect. There are special receptors (Chemical receptors ). Olfactory receptors are usually thin-walled pegs, cones, or plates with numerous pores through which airborne molecules diffuse.   Dendrites of sensory neurons branch profusely within these pores and may respond to very low concentrations of detectable compounds (e.g. sex phermones).   Some receptors respond to a wide range of substances while others are highly specific. Olfactory receptors are most abundant on the antennae, but may also be associated with the mouthparts or external genitalia.

*Taste receptors are commonly described as thick-walled hairs where the dendrites of several (usually up to five) sensory neurons are exposed to the environment through a single opening (pore) in the cuticle.   *Each neuron appears to respond to a different range of compounds (e.g. sugar, salt, water, protein, acid, etc.).   Taste receptors are most abundant on the mouthparts, but may also be found on the antennae, tarsi, and genitalia (especially near the tip of the female's ovipositor).

For many insects, love is truly blind For many insects, love is truly blind. Using sex phermones in a tube made really try to mate with that tube.

Tactile communication

Many insects depend on physical contact because they have poor vision and sound receptor. Blister beetles (family Meloidae), courtship begins with a series of antennal taps by the male on each side of the female body, and she signal her receptivity by lifting her wing covers and allowing him to clump on her back. Social insects, such as ants, often stroke and groom each other with their antennae and mouth parts. However, both touch signals and chemical signals may be involved in these behaviours.

Bees dance

Bees communicate by dance language. Bees use dance as a form of communication for distance and direction of food sources or nest sites. 1- Round dance (running in a circle, is performed for close sites)

2- Transitional (or sickle) dance, For sites at an intermediate distance from the hive. This dance involves running in a semicircular (or moon) shape. 3- Waggle dance, the most complex of the dance types performed by honeybees.

Bee Waggle Dance The waggle dance is a language used by honey bee Apis mellifera. Which give the bees the ability to communicate the food sources locations. The dance consists of different units or words of honey bee language, these units consists of : 1- The pattern of the dance is conveying distance information. 2- The number of interactions of the dance that bee performs convey distance information as well. For example 100m = 9-10 interactions, 500m = 6 interactions, and 1500 m= 4 interactions.

The liveliness of the dance conveys information about the quality of the food source. (The more excited the bee appears the better the quality of the food). The angle of the dance conveys the direction of the food source The bee will stop her dance and give out a food sample at other bee request. Bee produce a sound to get attention of bees and to keep their attention. The distance measurement by measuring the energy used in the fly.

Acoustic communication

Sounds are caused by vibrations that can pass through air, water, and solid structures because sound waves move rapidly through air, acoustic signals can be quickly started, stopped, or modified to send a time sensitive message.

Although people can hear crickets, many insects make supersonic sounds that are above a person's range of hearing. These supersonic sounds have more than 20,000 vibrations each second. some grasshopper and moths produce ultrasonic sounds as 80000 hertz. Entomologist can study these sounds by using Audi-transducer.

Most insects detect sounds with a tympanic membrane in their abdomen (e.g. grasshoppers and moths) or in the tibia of the front legs (e.g. crickets) Grasshoppers rub their legs against their wings to advertise their presence. Many true bugs, beetles and ants make sounds by rubbing various other body parts together

Vibrational communication is widespread in insect social and ecological interactions. - Insects used water surface or plant surface to produce vibrational sounds. Plants are the most widely used substrate for transmitting vibrational signals. Plant species can vary in their signal transmission properties.

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