If you just look at their DNA, the various South American songbird populations all look pretty much the same. But their outward appearances and the songs they sing couldn't be more difficult. We're witnessing the birth of multiple new species.
There are lots of animals, including dogs and apes, that can communicate in something we might understand as sentences. But only one non-human species has complex enough communication that they actually need grammatical rules. Say hello to the Bengal finch.
Like humans, zebra finches form monogamous partnerships in order to rear children. And, very much like us, these birds are also known to indulge in "extramarital" sex, even when these affairs serve no obvious evolutionary purpose.
Reading Jeff VanderMeer's latest novel Finch, out this week, you're tempted to make up descriptors like "biosteam" and "spore noir." Inventive and haunting, the book is a hardboiled detective story set in a city overrun by spore-hacking mushroom people.