Birder's Guide

DEC 2018

Birder's Guide is the American Birding Association's newest publication. Each issue focuses on a key subject, providing tips from experienced birders on a wide variety of topics like Travel, Listing & Taxonomy, Gear, and Conservation & Community.

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Page 16 of 43

15 December 2018 | Birder's Guide to Listing & Taxonomy of New Zealand, in the bird tree of life based on short pieces of DNA extracted from 3,000-year-old bones. Just as DNA technology has allowed us to zoom into specimens and translate their smallest particles into large and po- tent volumes of data, so rocket science has zoomed us out into space, where in- formation from Earth-orbiting satellites allows us to place specimens in the global context of their habitats. During his ex- peditions, Lamb only had time for spar- ing remarks on the habitat at each of his sites. "This place is abundantly wooded with small live and white oaks and small pines," Lamb wrote in 1941 from an un - certain location in the Mexican state of Nayarit. Now, with weather stations and orbiting satellites, we can tap into global databases on temperature, rainfall, tree cover, even the height of those small oaks Lamb noted, for any location on Earth. Before we could activate these data for Moore Lab specimens, we had to locate each of Lamb's collecting sites as precisely as possible on a map. This is not as easy as it sounds. The job would require a virtual retracing of Lamb's route from above. Col- lections Manager James Maley and a small cadre of students, armed with Lamb's field notes, old gazetteers of historical place names, and Google Maps, followed Lamb through 22 years of mosquito bites, bro- ken-down trucks, and ornery mules. They dropped a digital pin at each collected bird, securing the connection between the specimens and those space-borne ecologi- cal data. When these sources of data are put together, we can use them for what is called integrative taxonomy, where the units of biodiversity are delimited and grouped using evidence from the pheno- type, the DNA, and the habitat of species. But the physical specimen remains the key. The specimen, the material evidence of a bird in a particular place and time, connects phenotype to DNA to habitat to whatever new source of information future breakthroughs might reveal. Ironically, the Moore Lab collection is now ripe for this kind of study exact- ly because it fell off the map for awhile. A lot of collections did. In the 1980s, as researchers turned to molecular biol- ogy, and especially DNA, as the hot new source of biological information, they cast off specimens as relics of an antiquated science. Like most new converts, they were absolutists. From the 1980s to early 2000s, research in collections declined, and, with the usual lack of foresight, col- lections were shuttered, given away, or, in the case of one collection, simply turned out onto the streets. As methods for DNA sequencing of museum specimens gained speed and fell in cost, this trend began to reverse. Now we recognize museum col- lections, even those dating to the Victorian Era, as invaluable storehouses of genomic information, like digging up time capsules that offer to tell us something about both our present and our future. One of these time capsules at the Moore Lab focuses on an elusive bird, the Unicol- ored Jay, a bird Lamb began to collect in numbers in the 1930s. In 2012, one of my students, Madhvi Venkatraman, now a graduate student at the Smithsonian's Na- tional Zoo studying invasive birds in Ha- waii, decided to take up where Moore and others had left off. To our 85 specimens in the Moore Lab, she added another 100 from museums like the Field Museum in Chicago and the Museum of Comparative Zoology at Harvard. After two years work- ing on the Unicolored Jays outside of her normal classes, once stealing away from an out-of-town family gathering to visit their local museum, her results showed differ- ences between Unicolored Jays that far ex- ceeded what Moore and others had specu- lated. It was clear that Unicolored Jays in five cloud forest patches were distinct. The DNA, degraded but still viable, revealed a surprise. The oldest split in Unicolored Jays, which occurred across a lowland pass in southern Mexico called the Isthmus of Tehuantepec, dated to three million years ago, about the time our ancient hominid relative "Lucy" was wandering the savan- nas of Africa. As for the habitat data collected by re- mote eyes trained from outer space, results supported the notion that all Unicolored Jays lived in some kind of cloud forest, but the cloud forest was a little different from one patch to the other. Some Unicolored Jays lived in forest where the trees were taller, for example, while others lived where the climate was cooler with more rain. Were these differences important to the jays? It is difficult to say. But the n Robert T. Moore inspects a Tufted Jay, a species first collected by Chester Lamb and described by Moore in 1935, in the Moore Lab at Occidental College. Photo © Occidental College

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