An international team of scientists has reconstructed the tree of life for all major lineages of passerines (perching birds).
The team, led by Louisiana State University researcher Carl Oliveros, extracted and sequenced DNA from 221 specimens representing 137 passerine families.
The scientists used these sequence data to understand how passerine species are related and to study when and how passerines diversified in relation to Earth’s history.
“In addition to inferring how these species are related, our in-depth study found that changes in global temperature or colonization of new continents were not the sole drivers of passerine diversification, as previously suggested,” Dr. Oliveros said.
“Instead, our results indicate more complex mechanisms were at play to spark bursts of passerine speciation around the globe.”
The researchers reviewed the evolutionary relationships they reconstructed among all passerine families and found two African species, the green hylia (Hylia prasina) and the tit-hylia (Pholidornis rushiae), belong to a distinct new passerine family.
They also found molecular support for the recognition of five additional families that have been proposed in other studies, bringing the total number of passerine families to 143.
“By sequencing DNA from invaluable specimens using new technologies, we can begin to understand how species evolved over the course of millions of years at a resolution that is unprecedented,” said study co-author Dr. Brant Faircloth, also from Louisiana State University.
“This study is an exciting prelude to the types of analyses we can do for all bird families and all bird species, moving into the future,” Dr. Oliveros said.
The study was published in the Proceedings of the National Academy of Sciences.
Carl H. Oliveros et al. Earth history and the passerine superradiation. PNAS, published online April 1, 2019; doi: 10.1073/pnas.1813206116