00330nam a2200133 a 450000500170000008200200001710000060003711000150004324500500005825000120010826000390012030000210015971000160018020251203091600.0  a591.51,bD, beh  d_  aKrebs, JR.  aBehavioural ecology: an evolutionary approach  a3rd ed.  aOxfordbBlackwell Scientificc1991  axi, 482p, 23 cm.  aDavies, NB.