In 2003, Nasa found freshwater snails reproduced in space with 50% larger statoconia

Nasa researchers observed freshwater snails reproducing in space during a Shuttle mission. Their gravity-sensing organs, called statoconia, grew substantially larger in microgravity. Swordtail fish larvae also developed enlarged otoliths, which are similar gravity-sensing stones. This indicated a critical developmental period where altered gravity impacts stone size. The findings suggest these organs regulate to achieve a functional weight.