The Differentiation of Populations | 225 



Geospiza difficilis 

 Geospiza scandens 



Geospiza conirostris 

 Platyspiza crassirostris 



Camarhynchus psittacula 



Camarhynchus pauper 

 Camarhynchus parvulus 



Cactospiza pallida 



Cactospiza heliobates 



Certhidea olivacea 



Pinaroloxias inornata 



Feeds on large variety of soft, 



generally small seeds. 14 



Medium; forages on ground. Pre- 

 sumably takes soft seeds. 7 



Medium; rests mostly on Opuntia 



cactus. Feeds on a small variety 



of moderately hard seeds, also 



soft plant tissues and nectar. 11 



Large; habits poorly known but 



similar to G. scandens. 3 



Large; mostly in dense brush 



and high trees. Feeds mainly on 



fleshy fruits, soft to moderately 



hard seeds, young leaves, and 



flowers. 10 



Medium; forages in trees, brush, 



and occasionally on ground. 



Primarily insectivorous, ex- 



cavating fairly deeply into woody 



tissues, usually on larger 



branches. 11 



Same as C. psittacula, which it 



replaces on Charles Island. 1 



Small; forages in trees, brush, 

 on cactus, and on ground. 

 Primarily insectivorous, excavat- 

 ing less deeply than C. psittacula, 

 usually on smaller twigs and in 

 lichens. 12 



Medium; tanager-like habits. 

 Probes with stick or cactus spine; 

 primarily insectivorous. 7 



Medium; habits poorly known, 

 primarily insectivorous. Re- 

 stricted to coastal mangroves. 2 



Small; warbler-like. Forages at 



all levels in trees, occasionally 



at ground level. Takes only 



animal food, especially small 



larvae. 16 



Medium; reported feeding on 



ground and in trees. Presumably 



takes insects, nectar, and some 



fruits. 1 



Source: Modified from Bowman ( 1961 ', 



