This is an eastern red bat mum that has four nursing pups. (Yes, it’s the bat you brought us Laurie, we found another pup tucked under her wing!) She flies very well, as do two of her pups, the other two are not yet volant, but they all find each other the next morning. She is doing a great job raising these pups and we’re happy to help her get over that little glitch that found her grounded.
Eastern reds have four nipples. Both nipples on her left side are visible in this photo and it’s apparent that the lower one is offset, to the outside, from the midline of her chest. That offset allows all four pups to fit symmetrically so that all can nurse without overlapping. Overlapping would cause more jostling for position, attracting attention from predators, and so has been evolutionarily eliminated.