Science News | Watch what monarch caterpillars do when fed toxic milkweed sap | Science News @ScienceNewsMag | Uploaded March 2024 | Updated October 2024, 9 hours ago.
Age makes a big difference in monarch caterpillars' willingness to drink the defensive toxin-rich "milk" that wells up from wounds in milkweed plants, lab experiments show. It's dangerously gluey for the youngest and tiniest stage of monarch caterpillars. As they grow through five stages, they eventually switch from rejecting a pipette of it to eager drinking, as seen in this video. The finding suggests that rather than nipping milkweed leaves to let the sap run out and disarm the plant, the biggest caterpillars may actually be seeking it.
Read more: sciencenews.org/article/monarch-caterpillar-milkweed-butterfly-binge
Video: A. Betz, R. Bischoff and G. Petschenka/Proceedings of the Royal Society B 2024