lecture 4: Communication Flashcards
Define communication
When one animal responds to the signals sent out by another animal.
Define Signals
Conspicuous behaviour patterns which are often remarkably striking and also often are combined with body structures. For example plumes, crests and claws.
What could Animal flashing colours mean?
Animal flashing colours, could mean mating season. Colours to attract females.
Acts of communication tend to?
They can be fixed in form, which act as releasers for other actions. Also it is shown to develop very similarly in all members of a species.
What is a signal?
A message sent
What is a sender?
Who sent the signal
What is a receiver?
Receiver - Individual who receives the signal, producing a probability of behaving in an altered way because of the signal.
What is a channel?
Channel - How the signal is transmitted. E.g. visual or chemical.
What is the context?
the setting in which the signal is transmitted and received.
What is Noise?
Any background activity in the channel that is irrelevant to the signal while being transmitted.
What is Code?
The entire range of possible signals.
Explain signals within species?
Distinct signals for a species is not often in large numbers
It can sometimes mean that the same signal means different things to different recipients.
A wealth of information can be conveyed from one to another.
How is the form of signals determined?
The message is decided by the animal which encodes in a signal it sends.
However the meaning is what the receiver makes of it.
Sight, sound and smells are mostly used by animals, as well as touch & taste at closer quarters. (Electric)
What questions can be used to determine acts of communication?
What is the purpose of behaviour?
Has the signal evolved for the purpose of communication?
What are the 3 different selection pressures which operate on the animals signals?
What form of signal will travel best in the environment between the signaller & receiver?
What signal will do the best to stimulate the senses and the brain of the receiver?
how far do the interests of the sender & receiver coincide?
What are the three different channels of communication?
Visual
Auditory
Sense (Olfactory)
For a brightly coloured animal, why must there be a greater benefit?
During the communication between members of the same species, the risk comes when the predators cur in on this as a means of finding food.
What signals travel best through the environment?
Animals who can rely on vision will stick to communicating through visual signals
For those who don’t rely on vision might rely on tactile signals or even scent.
Mammals will rely on their hearing, sight and smell while at a distance, however they could be tactile if they are sociable.
The medium that the signal has to pass through also plays a part.
What are the uses of vision and disadvantages?
Vision is used to detect changes in posture and colour, but is only important for predators that hunt by day. It is best for the targeting of prey. However because of this it is bad for communication in dense environments, especially since distance transmitted is limited by the size of the signaller
When is vision most beneficial?
Vision is at its best in a more private environment for short range communication, commonly between mates or rivals.
Explain visual signals
The amount of light available will influence this
Wavelengths can be affected by for example Seawater which can cause it to be scattered or absorbed.
Species such as the Warblers which are bright are easily seen in darker habitats.
Visual signals can work over long distances.
Explain Audition in the environment
Communication is never private
It can pass through the environment rapidly upon signaling covering long distances and even going around corners.
Effective way of advertising
Several bits of information can be quickly transmitted at once
The pattern of the sent frequency can be sent quickly with little delay.
Explain sound in the environment
Light will cause the sound to decay as it passes through it: High frequencies will lose their intensity, however low frequencies don’t and can travel more effectively over long distance.
Sound can travel better through water, fish and whales can produce amazing range with their sounds.
What upper frequency can humans not hear?
Ultrasound - Beyond the upper frequency of humans(i.e. above 20kHz).
What lower frequency can humans no hear?
Infrasound – below the lower frequency of human hearing range(i.e. below 20Hz).
Explain Olfaction (smells) in the environment?
Smells will diffuse slowly through the environment
Wind can affect the speed and direction of the smell
Little information can be carried but can only be resent once the original sent dissipates.
Long distance detection
The signal will stay even after the animal has moved and will stay persistent.
Animals will have different scent glands of which have different purposes.
Can be used as a territorial marker
Plenty of information can be detected in such signals, for example, who the individual is, its reproductive state as well as how long ago the animal was there.
Explain scent in the environment
For insects and mammals, chemical signals are very well developed
Some scents are designed to last only a short time but also persist while the signaller is absent. While others are relayed over time, in intervals.
Scenting is boundary specific.
Could develop a compromise between persistence & good dispersal.
Give an example of costs for communication
Increased risk of predation
What minimises the risk of predation during communication?
The intense selection pressure
An example of a method for this is the European songbird, they will emit the same seep alarm call once a hawk is spotted.
All of the same species will have an almost identical call
Indication of the species of the caller is not needed
Characteristics can make it difficult to localise
Predators with poorer hearing might struggle to hear at the frequence of the emitted sound.
What methods of communication can be used to be deceitful towards predators?
A bird can drag its wing along the ground, this is done to lure the predator away from the chicks.
Moths can have large eye spots which is seen to mimic a larger animal.
Bright colours are used by insects that taste nasty in order to show their distastefulness.
Selection will most likely favour the transmission of false information.
What ways do animals Maximize information and manipulation?
Accurate communication between mates is essential for potential copulation.
Signals will be produced by the animal when it is to their advantage
In order to maximise their own inclusive fitness, animals will be selfish.
Manipulation is mostly the best way to observer how animals act instead of sharing information.
What do male toads do as competition for copulation?
Male toads will fight in order to take up the position of the amplexus, once a male toad reaches amplexus they will call out.
Amplexus: sitting on top of the females, waiting to fertilise the newly released eggs.
Explain the two points of view for messages and their meaning
There are two points of view, first the animal of which sent the signal (message) and the receiver (meaning). However it can be different, will Vary from place to place as well as may have peculiar traits.
What are the reasons for communicating?
Most animal calls used are affective
To discover the reason you need to study the particular situation of which an animal produces a signal.
The advantages involved for the signaller must be able to outweigh the disadvantages.
Give examples of predators that vervet monkeys have calls for?
Snake
Leopard
Eagle
Calls have precise meaning.
What are Advertising displays?
Males will normally advertise for a mate
Sexual selection has caused Lavishness to rise
Correlates with mating success and development
Expensive features
Displays aren’t always handicaps
What is the Handicap principle?
“Look at me i must be an extraordinarily fit!” Amotz Zahavi
What are Ornaments?
Ornaments - Status badges
For a large amount of birds dominance is what is associated with the special patterns shown on feather colouration
Dominant male house sparrow, will be given way by the sub-ordinate birds because of the status badge
Ornaments determined by testosterone
Explain the dance of the honey bee
Direction is indicated by the orientation, the orientation is determined by the angle between the sun and the food source found.
The further away the food the slower the dance, however the closer the food the faster the dance.
What is metacommunication?
This is a form of communication that doesn’t communicate information itself, however it will make the following signalling components eligible.
An example of this is with dogs, lowered forward part of the body shows that signals to come will be playful.
Playful aggression is a very important component for development and has evolved over time some convention.
What stimulates the sense organs and brain?
The receiver still needs to detect the signal
There is a selection pressure on signals
Different situation could have caused it to be evolved
The receiver may detect features from the environment
In order for the signal to be effective, it must be stimulating
A lot of signals could create an effect by being supernormal
How far do the interests of the sender and receiver conicide?
Is there a conflict between the interests of the signaller
& those of the receiver?
If one fled without a fight, both would gain
Rise of cheating or resistance to being cheated could be developed.
If interests coincide, there is no scope for cheating.
Leads to selection pressures.
How does Mimicry, deception and honesty effect communication?
Some receivers can be duped into responding against their own interests.
Hedge sparrow & cuckoo
Plovers lure predators away
Black & yellow hoverflies
However it can’t persist if the deception is common, keeping it uncommon will mean it will persist.
Give example as communication as language
Chimps are sociable animals, using sounds gestures and facial expressions. Some may have a hidden wealth of meanings.
