01897naa a2200265 a 450000100080000000500110000800800410001902400350006010000160009524501320011126000090024352011190025265000110137165000160138265300150139870000240141370000160143770000200145370000160147370000180148970000220150770000220152970000220155177300580157320655602022-05-19       2017    bl uuuu     u00u1 u    #d7 a10.1038/s41467-016-0012-y2DOI1 aGRÜTER, C.  aRepeated evolution of soldier sub-castes suggests parasitism drives social complexity in stingless bees.h[electronic resource]  c2017  aThe differentiation of workers into morphological castes represents an important evolutionary innovation that is thought to improve division of labor in insect societies. Given the potential benefits of task-related worker differentiation, it is puzzling that physical worker castes, such as soldiers, are extremely rare in social bees and absent in wasps. Following the recent discovery of soldiers in a stingless bee, we studied the occurrence of worker differentiation in 28 stingless bee species from Brazil and found that several species have specialized soldiers for colony defence. Our results reveal that worker differentiation evolved repeatedly during the last ~ 25 million years and coincided with the emergence of parasitic robber bees, a major threat to many stingless bee species. Furthermore, our data suggest that these robbers are a driving force behind the evolution of worker differentiation as targets of robber bees are four times more likely to have nest guards of increased size than non-targets. These findings reveal unexpected diversity in the social organization of stingless bees.  aAbelha  aParasitismo  aEvolução1 aSEGERS, F. H. I. D.1 aMENEZES, C.1 aVOLLET-NETO, A.1 aFALCÓN, T.1 aZUBEN, L. von1 aBITONDI, M. M. G.1 aNASCIMENTO, F. S.1 aALMEIDA, E. A. B.  tNature Communicationsgv. 8, art. n. 4, 23 Feb. 2017.