来自《耶鲁大学开放课程：心理学导论 第14集》

• 
  
  forcing some males to go mate-less
  这迫使一些雄性伴侣减少
• 
  
  and giving rise to competition to see
  并引起雄性之间看
• 
  
  who can mate with the most females.
  谁可以与最多的雌性交配的竞争
• 
  
  For females, however, females can always find mates.
  对于雌性 不管怎样 总能找到雄性
• 
  
  So, sheer numbers don't count.
  所以单纯的数量并不重要
• 
  
  But there's competition to mate with the right males,
  但雌性竞争的是与恰当的雄性交配
• 
  
  those whose offspring have the best chance of surviving.
  那样的后代存活率高
• 
  
  The competition now explains the puzzle we started with.
  这些竞争解释了我们之前的谜团
• 
  
  It explains why males are typically larger,
  解释了为什么雄性体型都比较大
• 
  
  and often why males have evolved special weapons.
  为什么通常雄性会进化出特殊的武器
• 
  
  These special weapons evolved for fighting other males
  这些特殊武器是为了与其他雄性
• 
  
  for reproductive access.
  竞争生殖权利而进化的