Meeting Abstract
Sacoglossan sea slugs are a group of small herbivorous marine gastropods which typically are dietary specialists on green macroalgae. Several species of sacoglossan engage in kleptoplasty, the process of sequestering chloroplasts stolen from algae inside of the slug’s own cells in order to photosynthesize. Because they gain energy from sunlight through photosynthesis, it is expected that photosynthetic sacoglossan species will spend more time in direct light than non-photosynthetic species. Phototaxic behavioral experiments were conducted on two species of long term photosynthetic sacoglossans and three species of non-photosynthetic sacoglossans. The photosynthetic species were significantly more likely to spend time in the light, demonstrating that photosynthesis provides a strong incentive for light exposure despite potential risks of predation. On the contrary, non-photosynthetic species either prefer shade or do not exhibit a strong phototaxic response. Examining differences between these two groups of slugs provides valuable insight into the impact that the evolutionary novelty of kleptoplasty has had on the ecology and behavior of these animals.
