Topic 10: Animal Communication – Study GuideCommunication ALWAYS involves 3 components: Production, Transmission, and Reception of a signal. A signal is the physical form, packet of energy, or matter in which a message is encoded.There is still some debate over what constitutes “communication” among animal behavior researchers. This debate sometimes revolves around the “intention” of the signaler – whether the signaler consciously intended a message to be sent or not. “Information” is not the same thing as a “message.” An animal can gain information from the environment for instance, but a message encoded within a signal implies intent on the part of the sender.Remember that the success or accuracy of signals and messages is completely dependent on the ability of a receiver to detect the signal with its sensory systems! So a signal can take many forms (visual, olfactory, electrical, acoustic, etc.) and this is highly dependent on the habitat or environment, but the receiver must be able to detect it. The “mode” of a signal refers to the sensory systems involved in receiving the message. Many communication systems are multi-modal, meaning that they use multiple sensory systems. Human communication uses both language(words) AND non-verbal cues such as body language, facial expressions, and intonation. Lyrebirds use acoustic and visual signals simultaneously to convey messages to conspecifics.[The field of animal communication is so vast that I’ve had to make choices regarding which examples to present in class or on the PPs. The two criteria I usedwere: those examples that are classics in the field (every student of animal behavior should know) and research that has or is currently the subject of study by UT professors and students.]Honeybee Waggle Dance. This is a complex communication system used by honeybee scouts to simultaneously convey the distance and direction of a good pollen or nectar source to other members of the hive. This was first elucidated by Karl von Frisch.The Round Dance is performed by a scout bee to indicate the presence of nectar or pollen at a relatively short distance from the hive.The Waggle Dance is performed on a vertical surface in a dark hive. It is basically a repeated figure 8. The distance to a nutrient source is conveyed by the number or duration of the waggle portion which is the middle of the figure 8. The direction in which the hivemates should fly is conveyed by the angle of the waggle portion relative to the vertical (gravity). An angle outside the hive is defined by the sun’s position, hive (the point of the angle), and the source of nectaror pollen. It is this angle that is communicated to the hivemates. The forager or scout bee can perform the waggle dance over several hours and changes the angle of the dance as the sun appears to change position in the sky so that the information received by the hivemates regarding direction is accurate.Karl von Frisch and his students tested the accuracy of the waggle dance through a series of experiments in which they provided a sugar source to a scout bee and thenwhile the scout was waggle dancing, they put out optional sugar sources at either different directions or distances from the hive. Although not perfect, the overall trend is that the waggle dance provides relatively accurate information.(You are strongly encouraged to access videos that explain the waggle dance. There is also a game encoded in the power points that can be of use in understanding the variables of the waggle dance.)How does such a complex behavior evolve? Martin Lindauer (one of von Frisch’s students) suggested a series of increasingly complex communication systems by comparing closely related species of bees. Stage 1: No distance or direction information. Buzzing by scout and the scent of flowers on the body which arouses the other recruits to leave the nest in search of the flowers.Stage 2: Distance and directional information indirect or passive. Scout bee leaves mandibular secretions on the substrate which can be followed by the hivemates.Stage 3: Separate distance and directional information. Distance communicated by pulses of sound, then the hivemates follow the scout outside the hive. The scout performs a zig-zag flight in the direction of the flower source.Stage 4: Distance and directional information conveyed simultaneously. Waggle dance.Leaf-cutter Ant Pheromonal and Stridulation cues. Leaf-cutter ants cut leaves(duh!), but they do not eat them. The location of good leaf sources is communicated by stridulation (rubbing body parts together, e.g. the gasters of leaf-cutter ants) cues if the leaves are close, and by pheromonal cues if the leaves are far away. Stridulation cues can also indicate relative quality of leaves – tender leaves are preferred. The leaves harvested by leaf-cutter ants are part of a complexagricultural system. Leaves are chewed into a pulpy mulch (like compost for a human gardener) and fungus is grown on the mulch. The fungus produce proteinsand sugars which is what the ants actually eat. Mold can devastate the fungus garden, but workers have mats of bacteria on their bodies which produce anti-biotics that help kill the mold. So, in this complex system there are living things: ants, leaves, fungus, mold, bacteria, and non-living things: proteins, sugars, anti-biotics; but only one animal: Leaf-cutter ants.Visual Communication. The type and number of photoreceptors restrict the ability of animals to see only within certain wavelengths of the electromagnetic spectrum. Animals can see wavelengths of light that are invisible to humans. Many insects such as bees can see ultraviolet light which is not detectable by humans.Visual communication can only be accomplished if the receiver can see the signaler. So, at night, in turbid waters, in the deep ocean, in heavy forests, etc. visual communication is useless or restricted. There is a negative correlation in birds between the number of color patches on a male (using visual communication)and the brightness of the habitat – more color patches in darker habitats and vice versa.If an animal changes the color of its body to indicate a message, then the duration of the color change must be commensurate with the message. A permanent color change should indicate a permanent message, such as the age of the animal. A semi-permanent change might indicate reproductive receptivity or position in a