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We here present the results of an analysis of the optical spectroscopy of 42globular cluster (GC) candidates in the nearby spiral galaxy M81 (3.61~Mpc).The spectra were obtained using the long-slit and MOS modes of the OSIRISinstrument at the 10.4~m Gran Telescopio Canarias (GTC) at a spectralresolution of $\sim$1000. We used the classical H$\beta$ vs [MgFe]$'$ indexdiagram to separate genuine old GCs from clusters younger than 3 Gyr. Of the 30spectra with continuum signal-to-noise ratio $>10$, we confirm 17 objects to beclassical GCs (age $>10$~Gyr, $-1.4<$[Fe/H]$<-$0.4), with the remaining 13being intermediate-age clusters (1-7.5~Gyr). We combined age and metallicitydata of other nearby spiral galaxies ($\lesssim18$~Mpc) obtained using similarmethodology like the one we have used here to understand the origin of GCs inspiral galaxies in the cosmological context. We find that the metal-poor([Fe/H]<$-$1) GCs continued to form up to 6~Gyr after the first GCs wereformed, with all younger systems (age $<8$~Gyr) being metal-rich.

Ages and metallicities of globular clusters in M81 using GTC/OSIRIS spectra