Indiana State University Newsroom

State researchers' new species discoveries published by journal

April 12, 2017

Indiana State University's department of earth and environmental systems was the first to publish research from a large project in East Africa describing three new species found in the sediments from an ancient lake in Ethiopia, Paleolake Hadar.

Joseph Mohan, a second-year graduate assistant, worked under Jeffery Stone, assistant professor of environmental geosciences, to identify and describe the new species.

"The Hominid Sites and Paleolake Drilling Project is an international project with around 80 scientists. We are working together to explore six different ancient lake sediments and their implications for past climates that were located near where early humans lived," Stone said. "Paleolake Hadar was depositing sediments about 20 kilometers from where the skeleton of ‘Lucy' (Australopithecus) was found."

Mohan and Stone were the first researchers on the project to come out with a research paper presenting new data they published the article in Phytotaxa, a journal that specializes in publishing new algal species.

"Essentially, we wanted to reconstruct climate and our fossil tools for doing this are diatoms. When we looked at that tool, we saw that the species were new to science. To name and describe them is the first step in figuring out what your tools means," Mohan said.

"Our intention is to inform paleontologist about climate changes using different fossils of many different types, diatoms are just one of many different types," Stone said. "It was a big accomplishment. This is a huge project and it is a very expensive project. There is a lot of pressure on us to get and publish results. One advantage of having this publication is that it showcases that we are advancing science with this type of research. This is really the start of many new scientific papers that will come out this year from our project."

Mohan and Stone are in the process of describing several more new species from these ancient lake sediments. Mohan recently visited IUPUI to use the scanning electron microscope and develop new research from the Lake Turkana site, which will likely produce up to four new diatom species. Stone was recently awarded a grant from the University Research Council help fund imaging of the new species using this type of microscope, which typically costs about $100 an hour.

By next year, they expect to describe six or seven new species, including species from Turkana Lake and the Baringo Basin, which will be the focus of their research this spring and summer.

"Our research sites are located in places where no one has previously explored," Stone said. "These samples are three million years old and found in ancient lake sediments from Africa. It is pretty easy to distinguish when we see a new species."

Mohan used a scanning electron microscope in Tucson, Ariz., for the three newly discovered species. Indiana State collaborated with the University of Arizona to use the microscope free of charge.

"Using the scanning electron microscope was super cool. You keep zooming in until you get one little speck, it is really powerful," Mohan said.

"It is startling for people who haven't used one before. What you might perceive as scale becomes confusing because you can keep getting closer and closer," Stone said.

Stone's next part of the project involves using these diatoms to describe landscape changes and determining how that potentially influenced early humans and their evolution.

Mohan is currently working on a paper where the diatoms he described are being used for ecological reconstruction. It is likely Stone and Mohan will have three or four more papers submitted for publication on this research project within the next few months.

-30- -- Joseph Mohan, a second-year graduate assistant at Indiana State University -- Joseph Mohan, left, a second-year graduate assistant, and Jeffery Stone, assistant professor of environmental geosciences at Indiana State University.

Contact: Jeffery Stone, assistant professor of environmental geosciences, Indiana State University, 812-237-2249 or

Writer: Abby Niepagen, media relations assistant, Office of Communications and Marketing, Indiana State University, or 812-237-3773