Stagodont marsupials, placentals and multituberculate mammals scurried underfoot. Placental mammals have a corpus callosum, unlike monotremes and marsupials. Neither marsupials nor monotremes possess a baculum. Modern monotremes have a low body temperature compared to marsupials and placental mammals, around . The interclavicle is absent in marsupials and placental mammals. The second subclass is divided into two infraclasses&colon; pouched mammals (the marsupials) and placental mammals. Pre-natal development differs between marsupials and placental mammals. Wombats are short-legged, muscular quadrupedal marsupials that are native to Australia. Phalangeriformes, which are more closely related to other Australian marsupials, such as kangaroos. Most marsupials, including bandicoots, have a bifurcated penis. Examples include, pigs, cattle, horses, primates, dogs, cats, rabbits, mice, marsupials, and humans. Genetic analysis suggests a divergence date between the marsupials and the placentals at . A variety of early mammals were present including multituberculates, marsupials, and insectivorans. Phalangeriformes are quadrupedal diprotodont marsupials with long tails. Unlike most other marsupials, the koala does not clean her pouch.