Although the northern cardinal and indigo bunting species in this picture differ in color (red and blue), they are both members of the same Cardinalidae family. In general, this family contains medium-sized to large-sized songbirds. They tend to possess stout, seed-crushing bills. (Wikipedia)
Northern Cardinal (Cardinalis cardinalis)
The Northern cardinal (Cardinalis cardinalis) is a bird in the family Cardinalidae. It is a common songbird in much of the eastern parts of the United States and Mexico. The male (photographed in this picture on the left) is striking red in appearance, while the female is a reddish-olive color, an example can be seen on this link (female cardinal).
Indigo bunting (Passerina cyanea)
The indigo bunting (Passerina cyanea) is a small seed-eating bird, also in the family, Cardinalidae. The male (photographed in this picture on the right) is bright blue in appearance. I’m not sure why it’s called an “indigo” bunting. I would’ve named it a “blue” or “cyan” bunting. Anyway, similar to the cardinal, the female is a much more muted with a brown appearance year-round. An example can be see here (female bunting) along with a couple of short videos of these beautiful songbirds singing.
The two images in this original “Northern cardinal and Indigo bunting” photograph were both taken in New York. I think that it looks great as a wrap-around print on a black, glossy ceramic mug, and is available for purchase.