Steven Crane Compiled Section Handouts. Human Behavioral Biology 2012

Do it differently and you probably won't have any offspring.

But what argument runs counter to that idea?

• Species do need to do it in their own way. Don't want to waste time mating with other species.

Know the basic vocab

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  Libido; attractivity v. proceptivity v. receptivity; motivation v. performance (ex. erectile dysfunction); desire v. arousal v. orgasm.
  

How do you do the randomized reporting to learn about "taboo" sexual behaviors?

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  Example from the '80's of whether a man had slept with another man.
  
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  You're the man responding:
  
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    If yes, just mark yes.
    
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    If no, flip a coin. Heads you mark yes (so you marked "the taboo answer" just due to the coin flip, not actual behavior). Tails you mark no.
    
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  Now you're the researcher
  
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    Take the number of "nos" you got and double it. That's the real number of no's. The rest are real "yeses"
    
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    For example: in actuality, 10% of the men had slept with another man.
    
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      Those 10% mark yes.
      
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      The other 90% have not, but 45% will mark no and 45% will mark yes.
      
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      So your responses will come in: 55% yes, 45% no.
      
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      You know that the "nos" are only half what they should be, so you know it's actually 90%no and 10% yes.
      

Why do females have orgasms? Some theories:

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  Sperm facilitation (increased vaginal fluid)
  
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  Post-coital exhaustion and sperm motility
  
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  Reinforcement quality – no evidence of higher fertility in orgasm-prone women though 
  
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  Some twin evidence for genetic influence, with caveats
  
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  Spandrel: necessary for males so same physiology in females. Parallel of nipples in men.
  

What are four intercourse-related male-male competitive strategies?

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  Copulatory locks
  
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  Sperm plugs
  
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  Spiders cementing other spiders' genitals
  
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  Other insects insert their own sperm into testes of other males (fun fact!)
  

For human sexual behavior, what behaviors were once thought to be unique but now not so much?

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  Things that once were unique, but now are not: nonreproductive sex, foreplay, variety, homosexuality, rape, masturbation, fantasy, foreplay
  

And what actually does seem to be unique?

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  Sex in private, egalitarian sex, marriage (and cheating), romantic love, the expectation of sustained romantic love
  
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    Ex. Divorce period = 2-4 years € humans are serial monogamous (move from one monogamous relationship to another with inter-birth interval)
    
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  Compared to other species, we’re kinda boring. Other species have hermaphroditism, sequential hermaphroditism, pseudohermaphroditism, parthenogenisis