Charles Darwin's Observations on the Behaviour of Earthworms and the Evolutionary History of a Giant Endemic Species from Germany, Lumbricus badensis (Oligochaeta: Lumbricidae)

Figure 5

Precopulatory behaviour and mating in the common earthworm (Lumbricus terrestris), observed during dark summer nights with special equipment. Both partners remain anchored in their burrows (distance of the holes ca. 7 to 8 cm) (a) and evaluate each other in an extensive courtship process (b), (c), (d). Copulation occurs via the reciprocal attachment of the clitella (see Figure 4) and results in the exchange of sperm (e), (f), (g). After 1 to 3 hours the worms separate and retreat into their burrows (h) (adapted from [32]).