Magical Mystery Flower

This flower has magically appeared in our garden. In fact, there are two such flowers growing there. We think that they may have come from the birdseed because they are near one of the feeders. But we have no idea what kind of flower it is. The photo shows a black seed pod that was once green. And there are also little yellow flowers on the plant, which stands at least 6 feet tall.

If any of you know what this might be, please tell me!

Update: Thanks to the power of Google I know now that this is called a Velvetleaf plant and is technically a weed!