The Burrabb are the non-terran originating species that I’ve spent the most time designing. They’ve been in my imagination in some form for decades. This version, from my 2001 Sentient 39 universe building exercise, is close to how I currently imagine them. Given that they’ve spread themselves across hundreds of systems and adapted themselves to a multitude of environments this could just be an example of one of the sub-races. The Burrabb have two sexes but a slightly more complex breeding cycle than human beings. Fertilization occurs in the mahas. At a certain point the (fetus? larva?) developing cubs leave the maha and finish their development in pouches in the herras. Imagine a social structure of a pride of marsupial lions in which the (not)male gives birth and the (not)females finish the gestation. Only not quite that. The mahas are about twice the size of the herras. A burrabb family has a single maha and two to ten herras.