Quantitative Matching of Clutch Size in Reciprocating Hermaphroditic Worms (Current Biology)

Picchi et al. show that hermaphroditic polychaete worms not only conditionally reciprocate egg clutches, but are also able to adjust the quality of their clutches to those previously received by their partners. This study suggests that cognitively unsophisticated animals can exhibit fine-tuned forms of reciprocation.