These octopuses use specialized muscles to open and close little sacs of pigment in their skin called chromatophores — and this little guy was probably responding to the black tabletop beneath its tank. (theverge.com)
The most abundant photosynthetic organism in the world sheds countless little sacs into the oceans, which could be having a dramatic impact on marine ecosystems, according to a new study. (sciencemag.org)
Our little Sac - area bake sale raised a few thousand, too. (eatthelove.com)