But what exactly makes us so special? It all comes down to a temporary, high-tech organ called the . 1. The Placenta: Nature’s Ultimate Life Support
Unlike (who give birth to tiny, underdeveloped "joeys" that must finish growing in a pouch), placental mammals take their time. placental mammal
: Crucially, it keeps the mother's and baby's blood from mixing. This prevents the mother's immune system from attacking the fetus as a "foreign parasite". But what exactly makes us so special
: We stay in the womb for a much longer period. This allows us to be born more mature and independent. placental mammal