Otherwise, 'we' simply wouldn't be here!!!! A. Problem

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The Origins of Mating Behavior

• Evolutionary Psychology
• Dr. Kelley Kline
• FSU-PC

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I. Mating Evolutionary Roots

• Darwin observed that many animals exhibited
  physical behavioral characteristics that
  appeared to hinder the animals chances for
  survival (e.g., colorful plumage of a peacock).
  Yet these characteristics appear to be selected
  for in nature.
• Class What was Darwins answer about why this
  phenomenon should occur, if it appeared to
  threaten the animals chances for survival?
• Darwin argued that some features are selected
  for and thrive in nature due to their
  reproductive benefits of passing on the genetic
  line, rather than survival benefits. THIS IS
  CALLED SEXUAL SELECTION!!

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II. What are the two forms of Sexual Selection?

• 1. Competition for a mate.
• 2. Preferences for a mate.

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A. Competition for mates

• Intrasexual selectionoccurs when members of the
  same sex compete with each other for access to
  members of the opposite sex.
• (E.g., two stags locking horns in combat, two
  lions fighting for access to viable females, two
  males getting into a bar room brawl fighting over
  a woman, etc.)
• Class Why do members of the same sex compete
  with each other for mates according to
  evolutionary theory??
• Characteristics that lead to success in these
  contests evolve because the winners are able to
  mate more often and consequently are more likely
  to pass on their genes.

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What are some characteristics exhibited by
intrasexual competitors that may increase their
chances of winning?

• Greater strength, intelligence, cunning,
  attractiveness, derogating rivals, etc.
• E.g., The stronger male lion will successfully
  either kill/scare the other male lion away,
  thereby granting the victor access to the females
  in the pride.

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B. Preferences for mates

• Intersexual selection members of one sex choose
  a mate based on preferences for particular
  qualities in that mate.
• Characteristics preferred by members of the
  opposite sex, evolve to become more common over
  time. Why Class???
• These characteristics evolve because animals
  possessing them are chosen more frequently to be
  mates, and as a result, their genes are more
  likely to be passed on.
• --Animals lacking desired characteristics are
  chosen less frequently to be mates.

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III. Sexual Strategies

• Like successful foraging for food, finding water,
  and building shelter, we dont approach mating
  behavior without a plan.
• Human mating behavior has evolved so that we
  choose mates who are desirable, reproductively
  viable, likely to invest in us, so forth. Why
  Class???
• In our evolutionary past, those who failed to
  mate successfully failed to become our ancestors.
  We all are products of an ancestral line who
  competed successfully for desirable and
  reproductively viable mates. Otherwise, we
  simply wouldnt be here!!!!

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A. Problems solved by Sexual Strategies

• We have several mating strategies we employ that
  are designed to solve specific mating problems.
• ClassWhat are some of the basic mating problems
  that need to be solved?
• Selecting a desirable mate
• Attracting a mate
• Replacing a mate
• Keeping a mate (mate retention, mate guarding)

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B. There are two basic types of sexual
strategies

• 1. Short term mating (casual sex) involves
  mechanisms designed to procure a mate for a short
  period of time.
• 2. Long term mating involves mechanisms
  designed to procure a mate for a long period of
  time (possibly life).
• Note We will learn that often similar tactics
  are used in both types of sexual strategies
  making it difficult for the individual to
  determine which type is being sought. For
  example, males often use deception (being overly
  friendly, generous with money gifts, to achieve
  short term mating goals, when the female may
  misperceive these gestures as pursuing long term
  mating goals.)

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Points about sexual strategies

• We are not always consciously aware of the sexual
  strategies we employ in mating.
• When we become aware of the strategies we are
  using to procure mates, it often impedes our
  performance.
• Buss, has examined these strategies in a study of
  over 37 countries and has found robust evidence
  to support these tactics as hard-wired in our
  systems. Its not a cultural phenomenon.

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1. Selection a Mate

• ClassWhat factors come into play when we select
  a mate???
• Its adaptive to select mates who
• Are willing to provide abundant resources
• Protect us our offspring
• Devote time, energy, money, effort in us.
• This increases the chances that our offspring
  will thrive and survive.
• Thus, we have evolved preferences to seek mates
  possessing these qualities.

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According to the evolutionary theory, do men
women seek the same characteristics in a mate??

• Class what do you think???
• No, men and women have different reproductive
  costs, which impacts the preferences they develop
  for future mates.
• As women have a greater physical investment
  bearing caring for children (40 week gestation)
  then men do, they seek more long term mates.

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2. Attracting a Mate

• Its not enough to select a mate, but we have to
  engage in behaviors to attract the mate we are
  interested in.
• Factors that have worked over time to procure
  mates are
• Competition
• Showing off ones attractive qualities (e.g.,
  peacock showing a peahen his gorgeous plumage,
  males flexing their muscles for female passerby)
• Derogating rivals
• Ingratiating oneself to the mate.
• Showing willingness to invest/commit (expending
  resources, being friendly/chivalry)

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Why do these factors work in attracting mates?

• If these tactics led to more frequent fruitful
  mating, then individuals using these tactics,
  would be more likely to reproduce pass on their
  genes.
• (e.g., elephant seals have evolved to become
  large and heavy, thereby strengthening their
  chances of mating with females in the harem
  warding off other male competitors.)

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3. Keeping a mate

• Just because we may select and attract a mate
  successfully, doesnt mean we will hold onto the
  mate indefinitely.
• We may lose mates because
• Another suitor may poached (stolen)
• One mate may defect due to the failure of the
  other mate to fulfill the defecting mates needs.
• A more desirable mate may come along.

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Mate Retention, Infidelity, costs

• Males who dont guard access to their mate, may
  risk raising a child who is not their biological
  heir. Hence, sanctioning his mates access to
  other males, is one way to decrease paternity
  uncertainty.
• Tactics employed mate guarding, restricting
  females access to other males, derogating
  rivals, violence towards other males.
• Females who dont guard their mates, may risk
  losing a male his resources to another female
  her offspring.
• Tactics employed mate guarding, keeping
  oneself physically attractive, befriending female
  competitors to keep them in check, derogating
  rivals.

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4. Replacing a mate

• Sometimes a mate shouldnt be retained, but
  discarded and replaced.
• Why class??
• We rid of mates when
• They stop offering resources (money, sex,
  support, etc.)
• They are cheating
• They are infertile
• They are hostile or harmful to us
• The benefits of losing the mate outweigh the
  costs (depends on what our market value is
  following the break-up)

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Reentering the mating market costs and benefits

• Class, what are the relative costs and benefits
  that occur for men and women as they reenter the
  mating market??
• How do the presence of children and age of a mate
  impact their relative value on the mating market??

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Conflict between the Sexes

• Men and women clash over resources (money,
  status, power) sexual access (frequency, etc.).
• Male desire for short term mating strategies get
  in the way of womens long term strategies.
• Men and women both complain about portion of
  domestic work and who gets off easier.

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Culture Context

• Although this course will focus on the
  evolutionary theory as it applies to mate
  selection, the influence of society and culture
  is still important in explaining our behavior.
• Its important to note that our mating behavior
  and social system have changed far more rapidly
  than our evolutionary history, such that over
  time our preferences/desires in mating may change.