I know this is a weird question, but I was watching a documentary on elephants the other day. Shown was a newborn calf nursing, and I noticed that the elephants nipples were placed just behind the front legs. I’d never really thought about it, but had rather expected that rather than individual nipples, elephants would have udders like cows and horses. Thinking about it, I realized primates and whales have similar nipple placements while pigs, dogs, cats, mice, squirrels, have multiple nipples in rows which makes sense as they typically have large litters. Hippos, cows, deer, horses, giraffes, and goats all have udders located just in front of their rear legs consisting of two or four teats. Possums have their nipples arranged in a ring on their abdomen. The platypus and spiny echidna lack nipples entirely and secrete milk from patches of skin on their abdomens. Anyway, is there a name for the different types of nipple placement and are their any other animals that have their nipples in front?
Primates, including Humans, actually have two rows of nipples, forming along a pair of lines (that have a name I can’t recall) running roughly from the armpit to the groin; it just happens that in most cases (but by no means all*), only the top pair of nipples are ‘switched on’ during development.
*Some people (myself included) have additional nipples, but nearly always somewhere along the formation line.
When I first saw the title, I tought it said ‘nipple replacement in animals’.
The “milk ridge”, IIRC.