Vegetative to reproductive phase transition in phototropic plants is an important developmental process and is sequentially mediated by the expression of micro-RNAMIR172. To obtain insight into the evolution, adaptation, and function ofMIR172in photophilic rice and its wild relatives, we analyzed the genescape of a 100 kb segment harboringMIR172homologs from 11 genomes. The expression analysis ofMIR172revealed its incremental accumulation from the 2-leaf to 10-leaf stage, with maximum expression coinciding with the flag-leaf stage in rice. Nonetheless, the microsynteny analysis ofMIR172s revealed collinearity within the genusOryza,but a loss of synteny was observed in (i)MIR172A inO. barthii(AA) andO. glaberima(AA); (ii)MIR172B inO. brachyantha(FF); and (iii)MIR172C in O.punctata(BB). Phylogenetic analysis of precursor sequences/region ofMIR172revealed a distinct tri-modal clade of evolution. The genomic information generated in this investigation through comparative analysis ofMIRNA,suggests matureMIR172s to have evolved in a disruptive and conservative mode amongst allOryzaspecies with a common origin of descent. Further, the phylogenomic delineation provided an insight into the adaptation and molecular evolution ofMIR172to changing environmental conditions (biotic and abiotic) of phototropic rice through natural selection and the opportunity to harness untapped genomic regions from rice wild relatives (RWR).