Yes the black Austrolop! rooster fathered them all. I have a mixture of hens, 2 rhode island reds, 2 white leghorns, 4 barred rock, and one solid black hen (she's probably an austrolop also as she has the dark legs). It is funny to see the offspring of the white leghorn because they are white but all were born with some black spots and the spots are now fading as they mature. Some are retaining a few black feathers.