In the spring of 2010, my job was to sort hundreds of dead anolis lizard specimens at Harvard University’s Museum of Comparative Zoology.
For several weeks, I stared at several gallon jars full of hundreds of these lizards preserved in alcohol, sorting these specimens, one lizard at a time, by species and the location where they had been collected.
I had been volunteering as a research assistant in the lab of Harvard’s evolutionary biologist Jonathan Losos, who is now a Professor of Biology at Washington University in St. Louis. There, I helped one of Losos’s Ph.D. students with an analysis project where we compared the body structure of two closely related species of anole lizards.
I was used to doing field research, like herpetology surveys, where we worked with reptiles and amphibians in the wild. I wasn’t sure I’d warm to a museum-based research project where I was confined to working in a lab with preserved specimens.
In an age of high-tech science, research involving museum specimens might seem like an anachronism. But museum-based projects are still very popular in biology, and in many respects can be as high-tech as other kinds of science, said James Hanken, developmental biologist at Harvard University and former director of Harvard’s Museum of Comparative Zoology.
Museums provide scientists with ready access to several kinds of biological materials such as preserved specimens that can be used for molecular analysis of tissues, as well as digital images for anatomical studies, which can all be used to understand and document biodiversity, for taxonomic research, and even understanding the impact of climate change on various species.
“For example, I'm sure that most people would be surprised to learn that many natural history museums, including the Museum of Comparative Zoology, maintain large "frozen collections" — basically, rooms with giant vats filled with liquid nitrogen, which contain plastic vials with tissue samples of tens of thousands of field-collected animals,” Hanken said.
“These samples are used in all kinds of molecular analyses, some of which are the most sophisticated and cutting-edge that you can find.”
Molecular and DNA analysis can help scientists map the genomes of various species. It has also helped scientists to determine the relationships between various organisms with more precision, which has resulted in many organisms being reclassified and given new scientific names based on their relationship to other organisms.
For example, the spring peeper, a tiny frog found throughout much of the eastern United States, was formerly classified under the genus Hyla, along with many tree frogs, but was later reclassified as belonging under the genus Pseudacris, when scientists found it was more closely related to chorus frogs.
Another high-tech area involves digital imaging, Hanken said. Examples include the open Vertebrate project, also known as oVert, which is funded by the National Science Foundation and is based at the Florida Museum of Natural History at the University of Florida. The project involves making micro-computed tomography (CT) scans of 20,000 fluid-preserved vertebrate specimens from US museum collections and producing high-resolution anatomical data for more than 80% of vertebrate genera.
CT scanning is a non-destructive imaging technology that can reveal internal characteristics of a specimen without having to dissect them. Internal features that can easily be observed through a CT scan include a specimen’s skeleton, muscles, circulatory and nervous systems, internal organs, parasites, eggs, and stomach contents, according to the project website — all the things you traditionally had to cut specimens open to observe and study. The anatomical images and data are then made available to scientists, educators, students, and even the general public for research and teaching purposes.
“The oVert project is the first organized multi-institutional approach to create 3D data available on a large scale for a major group of organisms and make it freely available on-line for research and outreach,” said David Blackburn, principal investigator of the oVert project at the University of Florida.
Museum collections remain critical to understanding and documenting biodiversity, Blackburn added. As of January 2022, the oVert project had generated approximately 25,000 media files for greater than 12,000 specimens.
“Information from museum specimens are used now more than at any other time in history,” Blackburn said. “That might seem a bold statement, but consider that the metadata associated with specimens is served freely on-line from most major museum institutions in the world.”
Comparing the current distribution of organisms to their past distribution could help scientists determine the impact of climate change and if the distribution of various organisms is changing as the world’s climate changes.
Richard Primack, conservation biologist at Boston University, said that museum collections of plants are extremely important to scientists who are carrying out research related to the classification of organisms. It can help them determine plant distributions and compile inventories of plant species for particular geographic locations over centuries.
“Herbarium collections [preserved plant specimens] have taken on added significance as they can be used to carry out phenology research, showing how sensitive plant species are in terms of flowering and leafing [in relation] to the fluctuating temperatures of climate change,” Primack said.
Research using herbarium specimens to detect the signature of climate change is a rapidly expanding field as hundreds of thousands of herbarium specimens are becoming available on-line, Primack said.
Primack is using herbarium specimens to look at the possible effects of climate change on plant species around the Walden Pond area in Concord, Massachusetts, where Henry David Thoreau and other naturalists kept precise historical records of the living species and the environment. He wanted to see what plant species were present in the past, but might be locally extinct now, and if the timing of phenological events like leafing and flowering have changed in recent decades.
Martha Munoz, an ecologist and evolutionary biologist at Yale University, said that natural history museum collections are like libraries full of organisms. “Whenever we want to be inspired by ideas, take stock of what we know, or access information to test a concept, we can leverage the information stored in collections much like we do with manuscripts.”
Collections can reflect decades, or even centuries, of care and investment, Munoz said.
“As such, they provide a temporal lens that contemporary studies cannot achieve. For example, museum collections have proven useful for assessing how climate change is impacting the body sizes of organisms. Without specimens, this type of research would not be possible.”
In the spring of 2013, we completed our work on the anolis lizard research project. In addition to learning new skills, such as how to use x-rays on specimens, I also found museum research to be just as interesting and exciting as field research. Preserved museum specimens can reveal information important to scientific studies, just like live specimens in the wild can.
In that sense, museums are not anachronisms, but rather, they are an important part of modern biological research.
