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We studied foraging behaviour of two sympatric rodents (Meriones meridianus and Dipus sagitta) in the Gobi Desert,northwestern China.The role of foraging behaviour in promoting species coexistence was also examined.We used giving-up densities (GUDs) in artificial food patches to measure patch use of rodents and video trapping to directly record foraging behaviour,vigilance,and interspecific interactions of rodents.We collected data for 59 recognizable individuals (23 M.meridianus and 36 D.sagittta) for a total of 562 tray visits.Four potential mechanisms of coexistence were evaluated: (1) microhabitat partitioning; (2) spatial heterogeneity of resource abundance with a trade-off in foraging efficiency vs.locomotion; (3) temporal partitioning on a daily scale; and (4) a seasonal rotation of foraging efficiency.Compared to D.sagitta,M.meridianus generally possessed higher GUDs,spent less time on patches and conducted less visits per tray per capital,regardless of microhabitats.However,M.meridianus possessed advantages in average harvesting rates and direct interference against D.sagitta.Our results only supported the fourth of the mechanisms listed above.We proposed another potential mechanism of coexistence: a trade-off between interference competition and safety,with M.meridianus better at interference competition and D.sagitta better at avoiding predation risk.This mechanism was uncommon in desert rodent systems studied before.