Why are humans the only animal that has to cut the umbilical cord upon giving birth to their young? No other animals in nature have to do this. Or am I missing something?
Humans: yes you could leave the cord unsevered,but then it would be attached to the baby and placenta until it drooped off, with blood splattered all over the place. More convenient to cut it.
Animals....not all animals have umbilical cords, but those that do usually severe it by biting.
"Sqad, how long after birth would a human umbilical cord/placenta drop off? And would it drop of at the naval?"
I don't know the answer to either question as there are very few doctors (if any) have seen a live foetus attached to a placenta by the umbilical cord for more than a minute or so.......sorry.
Sorry if it's unclear - if baby is delivered and cord not severed then placenta delivered and all are left attached - then 3-10 days later the cord would dry up and drop off, quite close to baby.