I've started a new game and have gone back to check on all other tribes, now none of them are getting any. Even my initial tribe that got a bunch before.
_________________________
Windows Vista Home Premium/Toshiba Satellite A135/Intel(R) Core(TM) 2 CPU/1.6 GHz/1014 MB Ram/DirectX10/VRAM 224 MB/1280x800(32 bit)-60 Hz Display