CLOSE
Matthew J Parker, Wikimedia Commons // CC BY-SA 3.0
Matthew J Parker, Wikimedia Commons // CC BY-SA 3.0

How Scientists Use Old Museum Specimens to Make New Findings

Matthew J Parker, Wikimedia Commons // CC BY-SA 3.0
Matthew J Parker, Wikimedia Commons // CC BY-SA 3.0

More and more researchers are making new discoveries using old museum specimens. By digging through archives and collections, they've identified scores of new species, including the teddy bear–like olinguito and the Ruth Bader Ginsberg mantis.

Now, scientists examining cyanobacteria found during an expedition in Antarctica more than a century ago have made a surprising find: It looks an awful lot like the bacteria living there today. Their report on the bacteria’s stability appears in the Proceedings of the Royal Society B.

Cyanobacteria are itsy-bitsy organisms that have occupied Earth’s fresh and salt water for more than 3.5 million years. Also known (inaccurately) as blue-green algae, these single-celled microbes grow in clumps, balls, and sheets all over the world—even in the punishing cold of Antarctica.

Microscope image of Tolypothrix cyanobacteria
Tolypothrix cyanobacteria under a microscope.

The earliest expeditions to Antarctica had multiple goals, including scientific study. During the Discovery Expedition (1901–1904), Captain Robert Falcon Scott and his team fished a soggy mat of cyanobacteria from Lake Joyce. They brought the mat back to London’s Natural History Museum (NHM), where it was examined, pressed like a flower between sheets of paper, and shelved for safekeeping.

Fast-forward more than 100 years, and things aren’t looking so great for the Antarctic. Climate change is melting icecaps, changing the landscape, and altering plants’ and animals’ behavior and evolution. Researchers with NHM and the University of Waikato wondered if the same was true for the continent’s bacteria.

Anne Jungblut and Ian Hawes journeyed back down to Lake Joyce, where they used drills, cameras, and sediment traps to collect new cyanobacteria samples. Back in London, they retrieved Captain Scott’s algae mats from the archives. They compared the old and new samples, inside and out, scouring the mats for microbe fossils and sequencing their genes.

The results suggested that not much has been going on at Lake Joyce this past hundred years. The two groups of bacteria were remarkably similar, comprising the same species in the same proportions.

This could be good news, the researchers say. "We suggest that this relates to Antarctic freshwater organisms requiring a capacity to withstand diverse stresses," they write, "and that this could also provide a degree of resistance and resilience to future climatic-driven environmental change in Antarctica."

As genetic testing technology improves, museum-based discoveries like this one become more and more common. Biologist Evon Hekkala, of Fordham University, tells Mental Floss, "We are seeing time and time again (no pun intended!), that museum collections originally made for exploratory purposes can take on new and critical roles in helping us to understand the fine details of how living things are responding to our rapidly changing environment. They have helped in some cases to confirm that human activities are driving the loss of genetic diversity and in other cases to exonerate us. This paper is a nice example where we have a comparison across time that can help us to understand how resilient certain living things can be in the face of change. I always say that with museum collections time travel really is possible!"

Hekkala has herself made discoveries using museum specimens. She identified a new crocodile species lurking in the drawers of the American Natural History Museum (AMNH) when she took samples from two crocodile specimens collected from different sides of the Congo River, as she recounts in a recent episode of the AMNH video series Shelf Life: "I was dumbfounded when I looked at the DNA sequence. It turns out that one specimen represents the Nile crocodile species that we all know and love, and the other represents a completely separate species of crocodile. In fact, they’re so distinct that they’re not even each other’s closest relatives. They haven't exchanged genes in millions of years."

Hekkala says museum collections are more important than ever as climate change, deforestation, and habitat loss destroy our planet’s plants and animal populations: "These specimens represent an irreplaceable resource that can never be re-acquired."

nextArticle.image_alt|e
arrow
History
The Queen of Code: Remembering Grace Hopper
By Lynn Gilbert, CC BY-SA 4.0, Wikimedia Commons

Grace Hopper was a computing pioneer. She coined the term "computer bug" after finding a moth stuck inside Harvard's Mark II computer in 1947 (which in turn led to the term "debug," meaning solving problems in computer code). She did the foundational work that led to the COBOL programming language, used in mission-critical computing systems for decades (including today). She worked in World War II using very early computers to help end the war. When she retired from the U.S. Navy at age 79, she was the oldest active-duty commissioned officer in the service. Hopper, who was born on this day in 1906, is a hero of computing and a brilliant role model, but not many people know her story.

In this short documentary from FiveThirtyEight, directed by Gillian Jacobs, we learned about Grace Hopper from several biographers, archival photographs, and footage of her speaking in her later years. If you've never heard of Grace Hopper, or you're even vaguely interested in the history of computing or women in computing, this is a must-watch:

nextArticle.image_alt|e
iStock
arrow
science
Why Are Glaciers Blue?
iStock
iStock

The bright azure blue sported by many glaciers is one of nature's most stunning hues. But how does it happen, when the snow we see is usually white? As Joe Hanson of It's Okay to Be Smart explains in the video below, the snow and ice we see mostly looks white, cloudy, or clear because all of the visible light striking its surface is reflected back to us. But glaciers have a totally different structure—their many layers of tightly compressed snow means light has to travel much further, and is scattered many times throughout the depths. As the light bounces around, the light at the red and yellow end of the spectrum gets absorbed thanks to the vibrations of the water molecules inside the ice, leaving only blue and green light behind. For the details of exactly why that happens, check out Hanson's trip to Alaska's beautiful (and endangered) Mendenhall Glacier below.

[h/t The Kid Should See This]

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios