Koalas are notoriously strange little animals. They’re hyper-specialists, tied to the fragrant eucalyptus groves of Australia, where they somehow make a living off of toxic leaves. They sleep all day; babies eat their mother’s poop; and they succumb to gruesome diseases that don’t seem to affect other animals very badly.

Now, a team of researchers has sequenced the koala genome, finding clues about how the animals survive on eucalyptus leaves, how they sniff out the least toxic leaves, and why they are so susceptible to some diseases like chlamydia.

The number of koalas in most parts of Australia has declined precipitously over the past few decades, as the eucalyptus forests they inhabit have been shaved down to make way for