Question: how can you tell the difference between male and female hummingbirds?
Answer: Adult male Ruby-throated Hummingbirds (above left) have pointed rectrices (tail feathers) that are all dark with no white tips; the tail is forked. However, young males (above right)--like females of any age--have white tips on the outer three rectrices on each side; each feather is rounded and the tail is fan-shaped.