Dwelling beneath the soil’s surface are intricate communities of organisms whose very existence is vital to ecological health and well-being. While it is widely understood that these creatures are important, little is known about their direct relationship with plant communities, and far less is known about the sheer number of species that may exist. Dr. George Damoff’s life passion is to change that.
“In a square meter or yard, you can have hundreds of earthworms,” said Damoff ’80, ’87 & ’08, an SFA Division of Environmental Science adjunct faculty member. “In a typical acre of pastureland with good soil, you can have a million earthworms per acre.”
In the past year alone, Damoff has described and published information about two entirely new species — Diplocardia deborahae and Diplocardia hebi. And with the backlog of specimens awaiting dissection in his Dallas-based home lab, that number is likely to dramatically increase.
“This is a species from Oklahoma that is new to science,” Damoff said, holding up a vial containing an earthworm in SFA’s forest soils lab. “In Oklahoma and Texas, I have found nearly two dozen new, unnamed species.”
Although Damoff has discovered a number of other new species, they will not be officially recognized until his descriptions have been peer-reviewed and published in Megadrilogica, a scientific journal solely dedicated to the study of earthworms.
One of the new species now under review was collected on the banks of the Colorado River east of Austin and will be named in honor of Dr. Kenneth Farrish, director of SFA’s Division of Environmental Science and Hiram and Gloria Arnold Distinguished Professor. It was Farrish who introduced Damoff to megadrilology, also known as the study of earthworms.
“Earthworms are terribly important to how soils function,” Farrish said. “Our food depends on soil, our fiber products depend on soil, and it is not a renewable resource. I like to say that once you find out about earthworms, they’re not so lowly.”
Additionally, more than 150 miles west of Austin on the south bank of the Colorado River, Damoff discovered yet another new species, Diplocardia jamesi, named in honor of Dr. Sam James, a renowned researcher who mentored Damoff in earthworm identification.
“I think it’s neat that these two very important men who helped get me started will be featured in the same publication,” Damoff said.
Following peer review, these two species, like Diplocardia hebi, will be prepared as type specimens and housed in the Smithsonian National Museum of Natural History in Washington D.C.
“Sam James has collected and named a large number of species from around the world,” Damoff said. “When I got started, he told me I was going to find a lot of new species in Texas, but I don’t think he realized just how many.”
When listening to Damoff talk about earthworms, it’s difficult to imagine these organisms have not always been his singular passion.
He received his bachelor’s and master’s degrees in biology at SFA. As a graduate student, he focused on limnology, the biological study of lakes, rivers and other bodies of fresh water. It wasn’t until Damoff returned to SFA a decade later to pursue a doctoral degree in forestry that he discovered his calling while sitting in a forest soils science class taught by Farrish.
Damoff recalled that during one lecture, Farrish spent a seemingly inordinate amount of time focused on the importance of earthworms, as well as how very little is known about them.
“I sat off to the side of the class listening to him go on and on, and it was literally one of those situations when a light bulb went on over my head,” Damoff said. “I’m thinking, ‘I’m a biologist, and forestry has a need to know more about this biological organism.’”
Following this epiphany, Damoff waited two weeks before approaching Farrish to express his interest in conducting earthworm-related research.
“The first thing I said to him was, ‘My name is George. The name George means worker of the soil, and I should be working in soil,’” Damoff said.
Damoff explained the name George has Greek origins that translate to “farmer” or “worker of the Earth” — a fitting moniker for a megadrilologist.
To learn earthworm identification techniques, Damoff contacted James, then serving as associate professor at the Maharishi University of Management in Fairfield, Iowa.
“The best way I can describe those three days in the lab with Sam is when you go to the Big Sky Country, look up at night, see all those stars and you just marvel,” Damoff said. “The same thing happened to me microscopically when I studied the inside of an earthworm. I just marveled at everything that was there.”
In addition to conducting surveys across Texas and Oklahoma, Damoff also works with researchers and agencies from across the continent to dissect and identify vial upon vial of earthworms.
Diplocardia deborahae, one of his most recent discoveries, sat on a shelf at the Canadian Museum of Nature in Ottawa, Ontario, for nearly 50 years after being collected in Eastern Tennessee by fellow megadrilologist Dr. John Reynolds.
Damoff met Reynolds in the early 2000s, and when Reynolds realized Damoff was skilled in Diplocardia identification, he asked Damoff if he would be interested in identifying the more than 900 vials of earthworms collected during his decades of research.
Damoff jumped at the opportunity and spent a week at the museum processing the worms for shipment to his lab in Dallas.
“There are very few people who work with Diplocardia because in order to correctly identify the earthworms you have to go inside them, and many of them are 1 to 2 millimeters in diameter,” Damoff said. “People don’t have patience for that or are just not interested, but I never grow tired of it.”
In addition to Damoff’s search for new species, he also is greatly interested in exploring and quantifying the effect of non-native earthworms on different ecosystems.
“Invasive species are a pretty big problem,” Damoff said. “I suspect there are some pretty strong effects on hydrology and changes in plant communities, especially in lower areas.”
Damoff said that in the Northern U.S., non-native earthworms, often inadvertently introduced through imported plants and agricultural materials, are completely altering the forest floor and, subsequently, the broader forest ecosystem.
“In forests up North, you have a duff layer that’s a foot or more deep,” Damoff said. “These invasive species can actually obliterate it to the point where it’s just exposed mineral soil.”
Damoff explained that this leads to erosion and germination failure in plant species that depend on the thick layer of organic material.
“There’s actual data from a study conducted in the northern U.S. showing that these invasive earthworms impacted the browse to a point that it reduced the white-tailed deer population,” Damoff said.
As he moves forward with his pioneering research, Damoff can’t help but look back on the humble beginnings of his life’s work with a smile. As a child in Columbus, Ohio, Damoff and his two older brothers, coffee can and flashlight in hand, frequently scoured their backyard after dinner in search of earthworms to use as fishing bait.
“That was really the beginning,” he said. “I’ve wondered why it took so long for me to discover earthworms as my passion, but I’m not going to complain — I’ve certainly been enjoying it.”