Origin of male-biased sex allocation in orphaned colonies of the termite, Coptotermes lacteus

摘要: In eusocial insects, sex allocation often constitutes a ground for intracolonial conflicts. This occurrence provides ideal opportunities to test kin-selection theory. A vast literature on this topic is available social Hymenoptera, but the same field remains almost untouched in termites. preeminent case that of some species Coptotermes, where sex-allocation ratio nymphs shifts from near equity all-male when primary reproductives are replaced by neotenics. To shed light developmental origin shift, we compared various castes and instars primary- neotenic-headed mature colonies Coptotermes lacteus. The male-biased latter type colony results two concurrent events: first, youngest (larvae) 3:1 ratio; second, all female larvae become workers, while large fraction male proceed nymphal alate stages. Colony-founding experiments showed inbreeding itself cannot account bias at hatching. We suggest both genetic factors, due reproductive behaviour neotenics, environmental factors (colony condition resource availability) may influence process. Their exact nature respective impact have not yet been clarified.