A tammar wallaby joey stays close to its mother as it explores its enclosure at the Smithsonian's National Zoo on May 30, 2008. Tammar wallabies are marsupials -- like kangaroos -- and after birth ...

This has allowed invasive predators to wreak havoc on many vulnerable species. The tammar wallaby (Notamacropus eugenii), for ...

But seals aren't the only animals with extreme milk. If hooded seals drink the fattiest milk, then tammar wallabies prefer their milk loaded with sugar. It can contain as much as 12% sugar ...