- The researchers used molecular data from samples of museum specimens housed at the California Academy of Sciences in San Francisco to sequence the DNA and piece together an evolutionary history of two subspecies of Vermilion Flycatcher.
- The two subspecies were found to be so genetically distinct that the researchers elevated them to full species status and gave them the names Pyrocephalus nanus and Pyrocephalus dubius.
- Pyrocephalus dubius is found only on the island of San Cristóbal — or, at least, it was. The species, commonly known as the San Cristóbal Vermilion Flycatcher, hasn’t been seen since 1987.
Scientists say their research shows that two subspecies of songbirds found only on the Galápagos Islands should be elevated to full species status. There’s one big caveat, however: One of the two newly minted species may already be extinct.
The researchers used molecular data from samples of museum specimens housed at the California Academy of Sciences in San Francisco to sequence the DNA and piece together an evolutionary history of two subspecies of Vermilion Flycatcher. Their findings were published in May in the journal Molecular Phylogenetics and Evolution.
The two subspecies were found to be so genetically distinct that the researchers elevated them to full species status and gave them the names Pyrocephalus nanus and Pyrocephalus dubius.
Pyrocephalus nanus is found throughout most of the Galápagos, the researchers said, while Pyrocephalus dubius is found only on the island of San Cristóbal — or, at least, it was. The species, commonly known as the San Cristóbal Vermilion Flycatcher, hasn’t been seen since 1987.
“The population of dubius is presumed to be extinct, and thus would represent the first documented extinction of a Galápagos-endemic bird species,” the authors of the study write.
“A species of bird that may be extinct in the Galápagos is a big deal,” Jack Dumbacher, curator of ornithology and mammalogy at the California Academy of Sciences and a co-author of the study, said in a statement. “This marks an important landmark for conservation in the Galápagos, and a call to arms to understand why these birds have declined.”
Vermilion Flycatchers have a complex evolutionary history, according to the study. At some point in the past, they branched off from a common ancestral population into twelve subspecies with ranges spanning across the Americas and the Galápagos Islands. Dumbacher and colleagues examined the songbirds’ evolutionary history in light of current methods used to classify species and subspecies in order to look for any inconsistencies in how Vermilion Flycatcher lineages were established in the past.
Christopher Witt of the University of New Mexico, a co-author of the study, said that doing this work wouldn’t have been possible without access to museum collections such as the one maintained by the California Academy of Science’s — which happens to have the largest collection of Galápagos bird specimens in the world. “Preserved specimens can provide the crucial links needed to better understand how life on Earth evolved,” Witt said in a statement.
The scientists note in the study that it’s not clear what drove the San Cristóbal Vermilion Flycatcher to extinction, but they do point to two invasive threats as likely culprits: rats and parasitic flies. Rats climb into the birds’ nests and eat their eggs, while the flies can kill chicks. These invasive species have already had severe impacts on the remaining populations of Vermilion Flycatchers in the Galápagos. Some islands no longer host populations that once thrived there, per the study.
Searches for the San Cristóbal Vermilion Flycatcher on the easternmost island of the Galápagos archipelago, the only place on Earth the species is known to have existed, have found no evidence that the bird is still in existence. But Alvaro Jaramillo, a biologist at the San Francisco Bay Bird Observatory and a co-author of the study, argues that we shouldn’t give up on the species just yet.
“Wouldn’t it be great if the San Cristóbal Vermilion Flycatcher weren’t extinct? No one is looking, I’m pretty sure of that,” Jaramillo said in a statement. “At the very least, this discovery should motivate people to survey and see if there are any remaining individuals of the species hanging on that we don’t know about.”
CITATION
- Carmi, O., Witt, C. C., Jaramillo, A., & Dumbacher, J. P. (2016). Phylogeography of the Vermilion Flycatcher species complex: multiple speciation events, shifts in migratory behavior, and an apparent extinction of a Galápagos-endemic bird species. Molecular phylogenetics and evolution. doi:10.1016/j.ympev.2016.05.029