Staff & Student News
The Field Museum’s 4th Annual Undergraduate Research Symposium took place on August 11. A total of 17 summer interns presented the results of their research at the symposium. All eight interns from the Museum’s Research Experience for Undergraduates (REU) program presented talks, an additional eight undergraduate interns from around the museum also presented talks, and one high school intern presented a poster. The talks and poster were delivered very professionally, and their content underscored the high caliber of the research that the interns undertake during their time at the museum. Among the attendees of the symposium was incoming Field Museum President Richard Lariviere. The Field Museum thanks all attendees for their interest and support of the interns. Funding for the Undergraduate Research Symposium is provided by the Museum’s REU site grant from the National Science Foundation, (PI’s P. Sierwald and K. Angielczyk).
Research & Publications
This summer saw the publication of the “Illustrated Glossary of the Bivalvia,” coauthored by Curator Rüdiger Bieler, Research Associate Paula Mikkelsen, Postdoctoral Research Scientist Ilya Temkin (Zoology/Invertebrates), and other collaborators. The massive 209-page glossary, published as part of the Treatise on Invertebrate Paleontology (Treatise Online) series greatly extends an earlier anatomical glossary published by Rüdiger and Paula as part of the Florida Keys Molluscan Diversity project and now gives detailed descriptions and hundreds of illustrations for technical terms in bivalve research, covering both living and extinct taxa.
Assistant Curator Leo Smith and Postdoctoral Fellow Matthew Davis (both Zoology/Fishes) are co-authors of an article that recently appeared early online in the journal Proceedings of the National Academy of Sciences. The article, “Resolution of ray-finned fish phylogeny and timing of diversification,” provides the first comprehensive evolutionary tree of ray-finned fishes (all fishes except the sharks, rays, lungfishes, and coelacanths) based on DNA sequence data. By combining DNA sequence data from all major groups of aquatic bony fishes with a series of well-placed fossil fishes, the molecular tree can estimate the timing of all major splits in the evolutionary history of fishes. This “calibrated” tree of fishes allows ichthyologists to assess the ages of fish groups that could not be estimated because of the lack of representative fossils, which allows for investigations into the causes and consequences of their diversification during the last several hundred million years.
Resident Graduate Student Deren Eaton (Botany/University of Chicago) and Associate Curator Rick Ree (Botany) were the lead and correspondingauthors, respectively, on a paper published in the journal Ecology, entitled “Floral diversity and community structure in Pedicularis (Orobanchaceae).” The paper describes how community dynamics in this diverse genus—specifically, the interactions of closely related plant species sharing the same pollinators—may be accelerating the evolution of morphological differences between species, as well as increasing the rates of species birth and death. It contributes ecological and evolutionary insight into the longstanding questions of why there are so many species of Pedicularis (louseworts) and why their flowers display such great variation in color, size, and shape.
In the same issue, Rick was a co-author on a paper entitled “Synthesizing phylogenetic knowledge for ecological research.” In ecology, demand for information on species relationships is increasing, but bioinformatic resources providing this information are poor. This paper presents an approach for bringing together disparate sources of knowledge about the tree of life into a unified structure that can be used by non-specialists in systematic biology. It highlights the role of a software project called Phylografter initiated by Rick in the context of a working group meeting sponsored by the EOL Biodiversity Synthesis Center in 2009. Phylografter has since become a key part of Rick’s involvement in the new NSF-funded Open Tree of Life initiative.
Both papers were invited contributions to a special issue of the journal, with the theme “Integrating Ecology and Phylogenetics.” All articles in the issue are open access.
Research Associate Jake Esselstyn, Curator Larry Heaney (both Zoology/Mammals) and colleagues published a paper in early August in Proceedings of the Royal Society B that tests a genetic procedure proposed in the search for undiscovered species, using some Philippine bats as an example. The procedure, often referred to as “genetic bar coding,” uses a single gene drawn from many individuals of unidentified species to estimate how many species are present but previously unknown. This new paper shows that this procedure can either greatly overestimate or underestimate the number of species, depending on the rate of evolution and the size of the populations. Accurate discovery of species is likely to require detailed study of genetics and anatomy to produce a robust result; unfortunately, “quick and easy” methods don’t appear to work well.
Assistant Curator Leo Smith (Zoology/Fishes) is co-author of an article this summer from the journal Molecular Phylogenetics and Evolution. The article, entitled “Nuclear gene-inferred phylogenies resolve the relationships of the enigmatic Pygmy Sunfishes, Elassoma (Teleostei: Percomorpha),” reviews the problematic history of the pygmy sunfishes from North America and provides evidence from DNA sequence data that the pygmy sunfishes are the closest living relatives of the black basses, largemouth basses, and sunfishes from the family Centrarchidae.
In August, Graduate student Lu Yao, Regenstein Conservator JP Brown and A. Armor Watson III Curator Bob Martin (all Anthropology), together with co-authors Marco Stampanoni and Federica Marone (Swiss Light Source) and Karin Isler (Universität Zürich), published “Evolutionary Change in the Brain Size of Bats” in Brain Behavior and Evolution. The article examines the evolution of bat brain size by estimating brain volume in fossil bats using synchrotron radiation X-ray tomographic microscopy and comparing this to brain volumes for modern bats. The article was subsequently selected as the “Editor’s Choice” free text article for the issue and can be downloaded at the above link.
Processing of CT images of fossil bats and collection of comparative data from modern bats was carried out by Lu Yao in 2009 while she was an undergraduate studying Anthropology, Biology and Integrated Science at Northwestern University. Measurements on skulls of modern bats were conducted in the Zoology Department’s Division of Mammals, with help and advice from Negaunee Collection Manager William Stanley and Curator Lawrence Heaney. Lu’sproject was supported by an REU grant from Northwestern University, while Bob and JP had previously collected micro-CT data from the specimens using the synchrotron operated by the Federal University of Zürich, Switzerland. As far as the team is aware, this is the first-ever study of brain size in fossil bats.
Above Photo: Smoothed virtual brain casts reconstructed from 6 fossil bat specimens from 2 species of the family Hipposideridae: early Oligocene Hipposideros schlosseri and early Miocene Hipposideros bouzigensis.
Assistant Curator Leo Smith and Postdoctoral Research Scientist Matthew Davis (both Zoology/Fishes) attended the American Society of Ichthyologists and Herpetologists annual meeting in Vancouver, BC, Canada from August 8–14. Leo’s talk, “Evolution of the lachrymal saber with comments on the relationship between stonefishes and scorpionfishes,” discussed the evolution of a novel jaw-lachrymal locking mechanism in stonefishes and its implications for the evolution of these venomous animals. Some of the included drawings by Associate Clara Richardson (Zoology) were described in a tweet by a colleague from LSU as “The best illustrations I've ever seen of fish morphology.” Leo also co-authored a paper with H.J. Walker (Scripps Institution of Oceanography), “Establishing and maintaining tissue collections for DNA,” in the Technology and Innovation in Collections symposium on the current status of DNA tissue collections in the United States with guidelines for best practices.
Matt presented a talk (co-authored by Leo), “The evolution of bioluminescence and its impact on diversification in deep-sea lineages,” that through evolutionary analysis identified the 35 times that bioluminescence had evolved in vertebrates, exclusively in ocean-dwelling fishes. Matt also co-authored a poster on other deep-sea animals with Michael Ghedotti (Regis University), “Cephalic sensory variation within the deep sea ipnopid fishes (Teleostei, Aulopiformes),” that highlighted remarkable sensory specializations in fishes living in complete darkness and at 300-400 times the pressure that fishes experience in Chicago.
Assistant Curator Leo Smith (Zoology/Fishes) is co-author of an article that appeared early online in the journal Systematic Biology. The article, “The evolution of pharyngognathy: A phylogenetic and functional appraisal of the pharyngeal jaw key innovation in labroid fishes and beyond,” provides functional morphological and DNA sequence data evidence for the breakup of the incredibly diverse labroid fishes (cichlids, clownfishes, damselfishes, surperches, wrasses, and parrotfishes). For decades (and building on research from the 19th century), these fishes had been grouped together because of specializations associated with the throat teeth or pharyngeal jaws that had been identified in evolutionary biology text books as a classic “key innovation.” This study, building upon the work of several prior studies, definitively separates the core wrasses and parrotfishes from the remainder of the “labroid” fishes, and shows that this textbook example is wrong. Further, this study unites the popular aquarium-trade and majority of the labroid fishes (cichlids and damselfishes) with a diversity of other groups ranging from the eel-like blennies to the killifishes and flyingfishes in a new group, the Ovalentaria, that can be recognized by the group’s ability to lay sticky eggs on the surfaces of rocks or corals using adhesive elements.
Curator Emeritus Harold Voris (Zoology/Amphibians and Reptiles) was a keynote speaker at the Workshop on Freshwater Invertebrates of Southeast Asia: Biodiversity and Origin. His presentation was entitled “How a Dynamic Climate and Landscape in Southeast Asia During the Neogene Directed the Evolution and Diversification of Freshwater Vertebrates.” Other keynote speakers included Robert Hall (Geologist from Royal Holloway University of London) and Robert Morley (Paleobotanist from University of London). The workshop was held July 29th – August 4th, 2012 at the Taksila Convention Hall in Maha Sarakham Province, Northeast Thailand.
Resident Graduate Student Carrie Seltzer (Zoology/Mammals and UIC) gave a talk at the Ecological Society of America’s Annual Meeting in Portland, OR on August 10. Her presentation, “In search of sustainable seed harvest: Seed removal and establishment of an endemic African rainforest tree,” shared preliminary results from research in Tanzania following the fate of experimentally planted seeds to determine the feasibility of planting to mitigate seed harvest by humans
Fieldwork & Collections
A wonderful copy of Traitéde fauconneriewas donated to the Library by Charles W. Palmer and family. This two-volume set, published in Leiden (1844–1853), is considered the finest work on falconry which has ever been produced due to the life-size depiction and natural coloring of the species. The volumes contain 12 hand-colored lithographed plates of falcons plus two plates depicting the accessories of falconry. One of the most famous images is that of the “Groënlandais” or white gyrfalcon, illustrated at left.
Benton Postdoctoral Fellow Nicola Sharratt and Associate Curator and Chair Ryan Williams (both Anthropology) conducted archaeological excavations at the site of Tumilaca la Chimba in June–August with funding from the National Geographic Society and The Brennan Foundation. Excavations focused on five houses whose inhabitants were living through the disintegration of the Tiwanaku state. The data gathered from these houses will demonstrate how political disintegration affected household economics and the participation of local communities in larger economic spheres. The 2012 excavation team included graduate students from UIC and Northwestern, undergraduates participating on the UIC-Field Museum Archaeological Field School and students from Peruvian universities. See header photo: Tumilaca la Chimba Team 2012.
On August 13, former BioSynC Postdoctoral Research Scientist Joshua Drew (Columbia University, New York, NY) was featured in a Nature on-line article entitled “Shark-tooth weapons reveal lost biodiversity. Three shark species once found in the central Pacific Ocean are now missing.” The story highlights research findings resulting from Josh's time at The Field Museum, part of which was spent studying shark specimens. Photo left: Detail of catalog number 39681. - one shark tooth from Gilbertese weapon.
In February, Josh had gone on a tour of the Museum’s Fijian collections with Regenstein Collections Manager Christopher Philipp (Anthropology). During this visit Josh asked whether or not the Anthropology collections had any shark tooth weapons from the Gilbert Islands in Micronesia. While it was evident that there were many such weapons in the collections, the exact count was uncertain, as the database did not list materials for all probable objects. Christopherand Volunteer Katie Roberts (now at George Washington University, Washington D.C.) then performed an inventory of the materials used in the construction of all the potential weapons from the Gilbert Islands. They found over 100 objects with either one shark tooth or, as in most cases, many shark teeth, used in their construction. They also updated the Museum’s database to include all of the materials present in these collections. Between the months of February and May, Josh and Christopher made additional trips into the collection and pulled several cart loads of weapons to closely examine the types of shark teeth represented in each of the weapons. When Josh is finished evaluating these collections the identifications and photos taken during the visits will be added to the Museum’s database.
Sharks have played an important role in the culture and economy of the people of Gilbert Islands within the Republic of Kiribati. However, their reefs, like many throughout the world, have undergone a period of rapid and intensive environmental perturbation over the past 100 years. A byproduct of these changes has been a reduction of the number of shark species present in their waters. Using a novel data source—the Shark Tooth Weapons of the Gilbertese Islanders—Josh and the Regenstein team are reconstructingwhich species of sharks were present in the Gilbert Islands in the late 19th century, fully 50 years before the first western scientific ichthyologic inventories on the reef took place. Photo right: former volunteer Katie Roberts discussing shark tooth weapon with Josh Drew, Ph.D. - catalog number 9904 - which was part of the Hamburg Umlauff Museum collections received in 1905.
By comparing the high resolution images of the shark teeth on the weapons to field guides to sharks, and specimens within the holdings in the Division of Fishes, Josh and the Regenstein team has identified three shark species which are found on the weapons but were have not been recorded as occurring in the Gilbert Islands. However using nontraditional forms of data is not without potential pitfalls. This discrepancy between the historical record and observed findings could occur from the teeth originating in other areas, the shark species being overlooked or the species being extirpated from the waters by the time intensive fish surveys were carried out. There are extensive linguistic, ethnographic and material culture records supporting shark fishing as being an important part of the Glibertese culture. Coupled with few records of widespread trade networks, it is reasonable to assume that the vast majority of the shark teeth originated in fish that were caught by Gilbertese fishers. The species of shark that we have identified are conspicuous and have been easily identified by researchers in other studies where they co-occur and we have little reason to doubt that misidentification could cause this disconnect. Several studies have shown that shark populations are easily susceptible to population collapse and one cannot rule out that the species present in the 1840–1890s were not depleted to such low numbers that they were not recorded in subsequent fishery records.
Public Education & Media Coverage
On August 17, the new What the Fish? podcast episode focused on cartilaginous fishes (sharks!) in accord with this week being the Discovery Channel’s annual Shark Week. The podcast dives into various shark topics ranging from conservation biology and evolutionary relationships to feeding and functional morphology. Join the fish nerds every Friday—Assistant Curator Leo Smith, Postdoctoral Fellow Matthew Davis, Volunteer Eric Ahlgren (all Zoology/Fishes) and Outreach Coordinator Beth Sanzenbacher (BioSynC)—as they banter, debate, quip, and explore sharks. Please follow them on Twitter and tweet your shark (or anything fishy) questions to @FM_WhatTheFish or email@example.com. The podcasts are also available at iTunes here.
Collections Manager James Holstein (Geology) represented the Robert A. Pritzker Center for Meteoritics and Polar Studies and spoke at the Levy Senior Center on August 9 in Evanston, IL on the different classifications of meteorites and what can be learned from them. This event was hosted by the Illinois Science Council to educate the public on the Perseid meteor shower; which peaked on August 12.