KnowraPlacentaliaLinked fromLinked fromThe 23 pages that link to Placentalia, each with the reason it gives.All 23Broader topic 3Related 1Narrower topic 10Compared with 9ViviparityBroader topic: They are the most familiar example of viviparity with extensive maternal-fetal exchange.Evolution of mammalsBroader topic: Placental mammals became the most species-rich living mammal group.EutheriaBroader topic: Living members of Eutheria belong to this group, though the clade also includes extinct relatives.