Here's a phot of an adult male that I took at Ryan's school one afternoon (and since the place is full of House Finches, Song Sparrows and other potential host species, I can only imagine it was either originally raised there or was scoping out future possibilities).
Either way, it was definitely giving me the eye...
...and eventually decided to yell at me.
Here's an example of nest parasitism in action...I took this photo back in July during our trip to Pacific Grove, CA, up in Northern California. This is a juvenile Brown-headed Cowbird about to be fed by a White-crowned Sparrow.
First...the incessant begging...
...and then the sparrow uses its parenting skills on the other species.
Cowbirds may not be the most popular subject, but I do find their MO to be rather fascinating...makes me wonder about the very first Cowbird to do this in the distant past and what the circumstances were that led up to it.