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Published: January 12, 2012

What is a big discovery in ornithology?

John Bates, Curator and Section Head, Life Sciences, Negaunee Integrative Research Center

We often get asked to pick the biggest discoveries in our fields.  To me, this is only a part of what we are trying to do, but big things are worth crowing about.  So this is something I consider a big discovery that for reasons I do not fully understand has never got the recognition it deserved.  I may not be remembering the details with complete accuracy, but this is a story about discovering a new family and an adaptive radiation at the same time.

We often get asked to pick the biggest discoveries in our fields. To me, this is only a part of what we are trying to do, but big things are worth crowing about. So this is something I consider a big discovery that for reasons I do not fully understand has never got the recognition it deserved. I may not be remembering the details with complete accuracy, but this is a story about discovering a new family and an adaptive radiation at the same time.

Back in 2000, Tom Schulenberg, who is now at the Cornell Lab of Ornithology, was working for our Environmental and Conservation Programs. To me, he’s the person at the center of the discovery. At the University of Chicago, Tom did his doctoral work on Vangas, gathering DNA sequence data to better understand evolution of this well known and ecologically diverse radiation of Malagasy birds. But I am not writing about Vangas here, although they are an interesting story in their own right, Tom and others have just published a new phylogeny of vangas. No, I’m talking about the discovery of the family Bernieridae. 

Tom is both a skilled ornithologist and a birder, so while he was in Madagascar, not surprisingly, he did all he could to get to know all the birds of the island. He also collected specimens and tissue samples of many of those species. So did Field Biologist Steve Goodman, as he and Malagasy colleagues worked to document diversity around the country. As collection manager, Dave Willard would send subsamples of these tissues (we call them tissue loans, but the subsamples generally get used up)  to qualified researches making requests to include them into their gene sequencing projects to document parts of the evolutionary tree of songbirds. Tom has always taken an active interest in what such projects were uncovering. 

Madagascar has a number of brown, green and gray insectivorous perching birds, and what had always been most interesting about them is that they were morphologically and behaviorally similar to birds from Africa and Asia. So similar, that some were placed in the same genera with African species. The Madagascar birds included species placed in the same genus Phyllastrephus, as some African greenbuls (Pycnonotidae). Others small insectivores were placed in the Old World warblers, the Sylviidae. Still others that were larger and brown were placed with the Bulbuls (Timaliidae). Madagascar is full of mysteries, but these relationships made sense and had been accepted for over 100 years (with the exception of a couple of authors whose hypotheses had been ignored). That is until Tom started to think about this and knew that several people had gathered DNA sequence data for separate family-level projects on Greenbuls, Old World Warblers, and bulbuls. He contacted Alice Cibois, one of these researchers, who at the time was a post-doctoral fellow at the American Museum of Natural History. He suggested that she should get sequences of the Madagascar species placed in these three families and do a combined analysis with non-Malagasy birds. Basically, Tom had a hunch, and Alice’s subsequent analyses proved him right. 

The citation for their paper is:

Cibois, A., Slikas, B., Schulenberg, T.S., & Pasquet, E. (2001) An endemic radiation of Malagasy songbirds is revealed by mitochondrial DNA sequence data. Evolution, 55, 1198–1206.

Top to bottom: Cryptic Warbler (Crytposylvicola randrianasoloi) placed originally in Sylviidae, Long-billed Tetraka (Bernieria madagascariensis) placed originally in the Pycnonotidae (genus Phyllastrephus), White-throated Oxylabes (Oxylabes madagacariensis) placed originally in the Timaliidae. The 2001 paper of Cibois et al. used genetic data to document that all three are part of a radiation of birds endemic to Madagascar.

These Malagasy birds formerly spread across three different families were each other’s closest relatives. They formed a monophyletic group, a group endemic to Madagascar and a radiation of 11 species. Thus an adaptive radiation of species that were ecologically convergent on, but evolutionarily unrelated to greenbuls, warblers and bulbuls from Africa and Asia was "discovered." There have been lots of really exciting ornithological discoveries made using genetic data, but to find a new family and discover a new adaptive radiation at the same timehas to be on of the list of the most exciting things anyone has found in ornithology in the last 25 years.

John Bates
Curator and Section Head, Life Sciences

Contact Information

The tropics harbor the highest species diversity on the planet.  I am most intrigued by evolution at the tips of the tree of life.  My students and I study genetic structure in tropical birds and other organisms to address how this diversity evolved and how it continues to evolve as climates change and humans continue to alter landscapes.

We study comparative genetic structure and evolution primarily in the Afrotropics, the Neotropics, and the Asian tropics.  I am an ornithologist, but students working with me and my wife Shannon Hackett and other museum curators also have studied amphibians and small mammals (bats and rodents) and more recently internal, external and blood parasites (e.g., Lutz et al. 2015, Block et al. 2015, Patitucci et al. 2016).  Research in the our lab has involved gathering and interpreting genetic data in both phylogeographic and phylogenetic frameworks. Phylogenetic work on Neotropical birds has focused on rates of diversification and comparative biogeography (Tello and Bates 2007, Pantané et al 2009, Patel et al. 2011, Lutz et al. 2013, Dantas et al. 2015).  Phylogeographic work has sought to understand comparative patterns of divergence at level of population and species across different biomes (Bates et al 2003, Bates et al. 2004, Bowie et al. 2006, I. Caballero dissertation research, Block et al. 2015, Winger and Bates 2015, Lawson et al. 2015).  We also have used genetic data to better understand evolutionary patterns in relation to climate change across landscapes (e.g., Carnaval and Bates 2007) that include the Albertine Rift (through our MacArthur Grants, e.g., Voelker et al. 2010, Engel et al. 2014), the Eastern Arc Mountains (Lawson dissertation research, Lawson et al. 2015), the Philippines (T. Roberts and S. Weyandt dissertation research) and South America, particularly the Amazon (Savit dissertation research, Savit and Bates 2015, Figueiredo et al. 2013), and we are entering into the genomic realm focusing initially on Andean (Winger et al. 2015) and Amazonian birds (through our NSF Dimensions of Diversity grant). Shane DuBay is doing his dissertation research in the Himalayas on physiological plasticity in Tarsiger Bush Robins.  Nick Crouch, who I co-advise at U. Illinois, Chicago with Roberta Mason-Gamer, is studying specialization in birds from a modern phylogenetic perspective.  We seek to create a broader understanding of diversification in the tropics from a comparative biogeographic framework (Silva and Bates 2002, Kahindo et al, 2007, Bates et al. 2008, Antonelli et al. 2009).  João Capurucho (U. Illinois, Chicago, co-advised with Mary Ashley)  is studying phlylogeography of Amazonian white sand specialist birds and Natalia Piland (Committee on Evolutionary Biology, U. Chicago) is studying the impact of urbanization on Neotropical birds.  New graduate student Valentina Gomez Bahamon (U. Illinois, Chicago) is also working Boris Igic and me, after doing her Master Degree in her native Colombia on genomics and the evolution of migrating Fork-tailed Flycatchers (Tyrannus savana).  Jacob Cooper (Committee on Evolutionary Biology, U. Chicago) is studying the diversification of birds in Afromonte forests

Josh Engel and I are working up multi-species phylogeographic studies of birds across the Albertine Rift, based the Bird Division's long term research throughout the region.  We are working up similar data sets for Malawian birds.  Our current NSF Dimensions of Diversity grant on the assembly of the Amazonian biota and our NSF grant to survey birds and their parasites across the southern Amazon are generating genomic data for analysis in collaboration with paleoecologists, climatologists, geologists, and remote sensing experts from the U.S. and Brazil.  These large collaborative projects are providing new perspectives on the history of Amazonia.

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