性別比








性別比是指族群中雄性（男性）對雌性（女性）的比率。在人类中，出生男女的性别比大约为105:100。




目录






  • 1 類型


  • 2 人類以外生物的性別比


    • 2.1 自然環境


    • 2.2 自行控制


    • 2.3 人為控制




  • 3 相關條目


  • 4 參考來源





類型


性別比有以下幾個種類：



  • 第一性別比：指懷孕時的性別比

  • 第二性別比：指新生嬰兒的性別比

  • 第三性別比：指所有成熟個體（此指出生後至死亡）的性別比[1]



人類以外生物的性別比



Disambig gray.svg  關於人類的性別比，請見“人類性別比”。


自然環境



自行控制



人為控制


人類可能會無意間影響其他生物的性別比、或是會出於某些理由刻意控制某種生物的性別比。



相關條目



  • 有性生殖的演化

  • 重男輕女



參考來源




  1. ^ Nancy S. Coney and W. C. Mackey. 1998. "The woman as final arbiter: a case for the facultative character of the human sex ratio," Journal of Sex Research 35 (May): 169-175.




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