Confocal merged images of fertilization chambers of twice-mated females. Green sperm was transferred by the first male (tGFP1 line) and the red sperm (DsRedEx1 line) by the second male. In 3A, the fertilization chamber was dissected 24h after the remating and immediately observed. In 3B, the fertilization chamber was dissected seven days after the remating. The two squares at the bottom of each picture show, from the left, the single red and green unmerged images, respectively. Scale bar = 15 µm.