Photo of the day No larger than a grain of sand, the sea butterfly (Thecosomata) is a type of swimming snail, or pteropod, named for the way it propels itself through the water flapping its miniature fins like butterfly wings. Today, this wondrous deep-sea creature is in danger. Human-generated greenhouse gases are causing our ocean to absorb more carbon dioxide and making the water more acidic in the process. This is dissolving the shells of sea butterflies, often killing the animal inside. Much like a canary in a coal mine, the decline in sea butterfly numbers is a critical warning sign that we must prioritize the restoration of ocean health, including a significant increase in protection of the High Seas, where sea butterflies and many other astounding species are found. only.one/read/photo-of-the-d… – at Mexico