In the world of snails, the outcome of a “mutual encounter” is that both parties can “carry offspring“. Being a “hermaphrodite“, these snails often exchange sperm when they are “close together“. If one refuses to exchange sperm, the other instantly withdraws.
According to a recent report published in the journal Current Biology by expert Nils Anthens from the University of Tübingen, the reason for this “negotiation” among snails is quite practical.
As a “hermaphrodite” species, a snail can be both Female and Male. However, due to the complex and laborious process of sperm production, snail sperm is considered quite valuable. Based on research established over the past 20 years, snails typically prefer to fulfill the role of Female during reproduction. Therefore, if one of the two snails (at that moment) refuses to release sperm, the other immediately ceases any further interaction, aptly reflecting the saying “no payment, no service“.
The experiment involved over 200 individuals of a tropical marine snail species. In a group of 50 snails, experts prevented sperm production, meaning these 50 snails could still engage in mating, but could not release sperm in the final stages. When these 50 snails were paired with normal snails (those with functional sperm-producing organs), the healthy snails frequently withdrew, unwilling to continue the mating process.
This behavior reinforces the hypothesis (which has been around for 20 years) that hermaphroditic snail species require mutual sperm exchange, and the reproductive process of these species adheres to a natural and straightforward principle: No consent means no cooperation (meaning if one stone rolls away, the other must roll back).
