Download The theory of signal selection

The theory of signal selection
The handicap principle as a test for the information provided by signals
• Peahens prefer males with a long tail since the burden of the tail tests the information of the male quality.
• Neurotransmitters are toxic chemicals because their toxicity tests the quality of the interacting neurons.
• Signals are selected by a different selection mechanism (the handicap principle) that is different from the selection mechanism of all other traits.
• Natural selection functions by two distinct selection mechanisms
• The investment in signals (the handicap) is an essential component for creating a signal. The greater is the investment in a signal the better information it provides.
• The investment in any other trait is necessary to achieve the trait. But individuals gain if they can achieve the trait with less investment. •
Support to the theory:
• Signals, unlike other traits, lose their function when the investment in them is easy to the extent that everyone can signal alike.
• Money as a signal of wealth loses its value, its value is inflated, if all have easy access to it.
• Lace was a signal of wealth when lace was handmade and expensive, but lost its function as a signal of wealth when produced easily and cheaply by machines.
• The handicap principle should be understood as a test to the information provided by the signal.
• Properties of the test provide better understanding of the information provided by the signal than the response of the receiver to the signal.
• The signal, as a test, displays differences that would not be apparent without it.
For example: Although it is well known that a subgroup of students is the best in a class, once they are tested the differences among them becomes apparent. • Unless they were tested they would considered to be of equal quality
• I shall discuss only three social interactions in relation to the handicaps they impose:
• Testing the social bond.
• Suicide.
• Altruism
• If time allows‐ I shall discuss also human culture in relation to the interaction between the two selection mechanisms.
Trust, Testing the social bond
• Imposing a handicap tests the strength of a social bond.
• Love gestures, such as hand holding, deprives the holders from the freedom of using their hands.
• When children go to bed their parents read them a story which the children know very well. They prefer it to a new story because it enables them to assess (provides a standard) their parents’ bond with them.
Neurotransmiters as handicaps
• Neurotransmitters (chemicals deposited by a neuron connecting to another) in the brain are toxic because they are more efficient in producing reaction and can better assess the quality of neuronal connections.
• The same handicaps by noxious neurotransmitters that make efficient signaling in the young brain, by testing the neural connections, cause neurodegenerative diseases in old age.
Suicide
• The fact that suicide is a call for help is well known but why it should involve the risk of death is not appreciated.
• People climb the Everest although it is involved with a 10% risk of death.
• The risk suicidal individuals take in attempting suicide display reliably that they are desperate and seek help.
Altruism
• Competition among altruists to act as altruists
cannot be explained by models of indirect selection.
• Altruism provides social prestige to the altruist
• .Social prestige attracts collaborators and deters rivals
ALTRUISM
• Risking life in battle.
• Competition among pilots of fighting aircrafts to take a risk
• King Saul and David, The risk taken by David, The prestige David received and its importance.
• The importance of social prestige even in family life
• Altruism can be explained as a handicap that increases social prestige.
• If this is the case there is no room for models of indirect selection to explain the evoluition
of altruism, since altruism provides direct gain to the altruist
Evolution by the interaction of the two selection mechanisms.
• Signals increase fitness by increasing investment in the signal. • Other traits increase fitness by increasing efficiency to achieve a trait, i.e. by decreasing investment.
• Horns cannot evolve by the accumulation of small mutations that aims at producing horns in hornless species.
• They start from symmetrical protrusions that display the direction of gaze.
Art and basic research as signals
• The transition from stone culture to the culture of metals.
• The structure of the atom starting as investment in basic theoretical researc
resulted in the use of the atom as a source of energy.
• Kennedy and the technology of the 21st century.