In many locations in Canada you can find numerous species of native sparrows. Two that are pretty common, but look very similar are Fox and Song Sparrows. When seen individually it's easy to get the two mixed up. Fox sparrows tend to be larger, and darker. Song sparrows rustier reddish in color and not as dark brown. When you look at the two together, the differences become more obvious. Have attached a pic of each that I took here. The first is a Fox and the second a Song. Both have the dark chest spot, sometimes well defined, sometimes not.