354 



Relations within the Species 



10 20 30 m 



Fig. 9.17. Wood-ant trackways and nests at Picket Hill, Oxfordshire, England. 

 • =: nests, o = former nests, B = birch trees, G = gorse bushes, x = nests of wil- 

 low wrens. (Elton, 1932, Copyright, Cambridge Univ. Press.) 



Photo R. H. Beck, Am. Museum of Nat. Hist. 



Fig. 9.18. Territorial dispute in penguin colony, Bleaker Island, Falklands. 



