Songbirds are birds who belong to the clade Passeri (Passeriformes) and have a complicated and beautiful bird song. There are several thousand species of songbirds worldwide. They evolved approximately 30 million years ago on Gondwana, in what would become Australia, New Zealand, New Guinea, Sri Lanka, India, and Antarctica. At this time, songbirds would have been isolated from the rest of the world by the ocean. How did they come from being a small group living only on one island continent to living all over the world? About 25 million years ago, Wallacea formed. Wallacea was a string of islands stretching from (present-day) Australia to Asia. The songbird ancestors could fly from island to island until reaching Asia, and from Asia, the rest of the world. As songbirds reached new environments, they quickly began to adapt to their new homes, spurring a flourishing of new songbird species. They diversified amazingly quickly. Songbirds account for over half of all birds in the world. They reached that amount in just 25 million years when the most common ancestor of all birds lived just 95 million years ago. One theory about the rapid diversification of songbird species points to an additional chromosome that songbirds have, which is absent in other groups of birds. It’s this chromosome that may allow songbirds to sing so elaborately and learn the songs of other birds. The genes encoded on these chromosomes seem to be vocal learning abilities similar to those allowing human speech. And the genes are evolving rapidly. New species are formed through mutations of genes. The faster that the genes of songbirds mutate, the faster new species of songbirds are formed. This could be why they are so varied in so short a time. Songbird species vary in how they can learn new songs. Some species have only a short window of time after hatching in which they are able to pick up new songs, which some species are capable of continually learning throughout their lives. The number of songs a bird can learn varies by species, as well. About a third of songbirds have only one song, while about 20% have a handful. A few birds have hundreds or even thousands of songs in their repertoire! Large repertoires of songs may be favored by females when selecting mates, some evidence suggests. This would gradually move the species in the direction of learning more and more varied songs. However, some songbirds may stick to a few similar songs in order to identify locals and newcomers. If a new bird comes into the territory and doesn’t sing the same song that the local birds do, they might be a threat. Personalize a gift for someone special at no additional cost on Zazzle. The below banner contains an affiliate link for which I may earn a small referral. If you have any requests or questions, please feel free to leave them in a comment below. You can stay up to date with our blog on our Facebook, Twitter, and/or Pinterest. We publish a new blog about animals, fossils, or art every Tuesday and Friday, so until next time, thank you for reading and goodbye!