Like all ciliates, "Paramecia" reproduce asexually, by binary fission. Newborn "M. microlepis" may be feed firstly paramecia and rotifers. "Paramecia" feed on microorganisms like bacteria, algae, and yeasts. "Paramecia" live mainly by heterotrophy, feeding on bacteria and other small organisms. Paramecia are found in freshwater environments, and are especially in scums. These paramecia are rejuvenated in the sense of having a restored clonal lifespan. In research, adult zebrafish are often fed with brine shrimp, or paramecia. The same study suggested a molecular mechanism for learning in the "Paramecia". "Paramecium" strains possessing the particles are known as "killer paramecia". Fortuitously Raab also observed that light was required to kill the paramecia.