Mating and the sub-steps of sperm transfer. (A) A male with his tail positioned over a hermaphrodite's vulva after response, backing, turning, and vulva location. The inset shows the male tail after spicule insertion. Arrowhead denotes the tip of the spicules. The bracket denotes the approximate portion of the male shown in schematic in B. (B) Time (t) is equal to 0 when the spicules are tonically inserted into the vulva. The time it takes from t = 0 to completion of each sub-step is shown to the right of that step. Continued transfer was not timed, as it is simply the difference between the time from release to the cessation of transfer. For all times given, the minimum number of animals tested is 33. Note: 'valve' region is shown as open throughout this schematic as no morphological changes can be detected using the microscope we used to analyze sperm-transfer behavior.