June 6, 2024—Spring semester updates

We’re excited to have visiting Postdoctoral Associate Olmo Miguez-Salas, who started working in the Tarhan Lab in April. Olmo is visiting the lab from the Senckenberg Research Institute in Frankfurt, Germany. His work focuses on examining how temperature changes and low-oxygen events affect bioturbation intensities of some Long Island Sound trace makers. He conducts experiments using environmental control chambers and aquarium systems. Moreover, these experiments aim to validate the past record of similar trace fossils that are recorded through thermal or anoxic events. You can read more about his work on his Google Scholar. Welcome, Olmo!

Members of the Tarhan Lab helped organize the 2024 Northeast Geobiology Conference at Yale, led by our very own Maya! The conference had over a hundred attendees who were treated  to a tour of the newly reopened Yale Peabody Museum of Natural History and a keynote talk by YIBS Bass Visiting Scholar Tim Lyons. Brian also gave an exciting talk on his recent work looking at bioturbation intensities and biogeochemical cycling before and after the Permo-Triassic mass extinction!

Brian giving his talk about Permo-Triassic bioturbation.

Kate visited the US Geological Survey’s Core Research Center in Denver, Colorado to log bioturbation data and collect samples. This is part of her work investigating the effect of bioturbation intensity and style on sediment geochemistry during the Middle Paleozoic. She also gave an invited talk at the University of Southampton and attended a workshop on spatial methods for analyzing the fossil record at Oxford University.

Lidya and Silvi attended AbSciCon in Providence, RI in May. Lidya gave a talk and Silvi presented a poster on fossil silicification.

In addition to all the activities, this past semester Tarhan lab members had many accomplishments!

Silvi defended her PhD in May and moved to Chile to start a position as a professor at Universidad de O’Higgins. Congratulations Dr. Silvi, we’re excited to see the amazing things you will do next!

Undergraduate researcher Dana graduated and will be starting a PhD in geology at MIT in the Fall with Lyle Nelson. She was also awarded the National Science Foundation Graduate Research Fellowship and the MIT Dean of Science Fellowship! Congratulations, Dana, we’ll miss you!

PhD students Brian and Sydney were both awarded YIBS research grants. Brian will use his grant to continue conducting fieldwork on Permo-Triassic bioturbation and biogeochemical cycling in Svalbard, and Sydney will use hers to run geochemical analyses on the samples she collected from Bathurst Island last summer for a project on early land plants and the phosphorus cycle. Congratulations Brian and Sydney!

Sydney was also awarded a Heidemarie Johnson Scholarship from The Paleontological Society to attend this year’s International Geobiology Course, and Brian was awarded a Paleontological Society Research Grant to continue working in Svalbard!

Kate was awarded the EPS department’s Hammer Prize for outstanding graduate students. Those who know Kate know that she is extremely inquisitive, creative, hard working, and devoted to both her research and the EPS community. Congratulations, Kate!

Last but not least, congratulations to Lidya, along with co-authors Shuang Zhang and Martin Solan, who published a paper last month in Current Biology titled “Global distribution and environmental correlates of marine bioturbation.” Their work uses machine learning techniques to create a global map of bioturbation intensities and identify which environmental and ecological factors best correlate with bioturbation type/intensity. This work has major implications for predicting how bioturbation changes under different climate/environmental scenarios. The research was also covered by the Yale News, and you can read the article here!

February 8, 2024—Winter updates

With the new year and new semester we have some updates from Tarhan Lab members!

Over winter break PhD student Ashley Rivas revisited the Arrow Canyon Range in southeast Nevada along with colleagues from Smith College and Virginia Tech. They went back to some previously measured sections to get bioturbation data, and did recon work for future field campaigns.

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Finally, members of the Tarhan Lab are involved in organizing the 2024 Northeast Geobiology Symposium which will be held at Yale on April 12-13. NE Geobio is a student- and postdoc-run conference held annually for over a decade and brings together geobiologists from the northeastern US and Canada. Registration is open and abstracts are currently being accepted until March 8. More details can be found on the conference website.

November 7, 2023—Fall ’23 semester

It has been a busy semester for the lab! 

First and foremost, this semester we welcomed two new members to the lab–Maya LaGrange Rao and Dana Polomski! Maya is a Yale Institute for Biospheric Studies (YIBS) Donnelley Postdoctoral Research Fellow who joins us after completing her PhD at University of Alberta. Maya will be working on comparing Pleistocene and modern bioturbation in Willapa Bay, WA, to better understand the response of coastal bioturbation to climate change. Dana is a senior undergraduate EPS major at Yale who is working on Mesozoic bioturbation with James and mid-Paleozoic bioturbation and its impact on sediment geochemistry with Kate. Welcome Maya and Dana!

Maya has already made significant headway on her project—in late September, Lidya and Maya visited the west coast for five days of fieldwork at Willapa Bay in southern Washington. Joined by Brette Harris and Murray Gingras from the University of Alberta, they conducted preliminary fieldwork examining Pleistocene intertidal flat deposits, which will be followed by a more extensive field campaign in spring 2024.

                                       

                                               

                                                                      James and Dana logging sections in Wyoming.

August 2, 2023—Tarhan Lab summer activities

Members of the Tarhan Geobiology lab have had a busy summer filled with field work, trips, and conferences!

Postdoc Sophie Westacott wrapped up her year with us at Yale and moved to Bristol, UK to start a postdoc continuing her work on the silica cycle in the modern and in deep time. Best wishes to Sophie in her new position!

In May, Lidya, Ashley, Kate, and Sydney spent two weeks in the Great Basin (southern Nevada and western Utah) studying bioturbation and trace fossils preserved in shallow-marine carbonates deposited during the late Cambrian to mid-Ordovician. They were joined by colleagues from Virginia Tech (Ben Gill) and Smith College (Sara Pruss) and their students as part of a NASA exobiology grant to study the geochemical and paleobiological conditions between two of life’s greatest radiations: the Cambrian Explosion and Great Ordovician Biodiversification Event. 

In June, Kate and Sydney continued working in the Great Basin for Kate’s PhD project searching for signs of bioturbation and the development of the marine sediment mixed-layer. They worked on Devonian and Carboniferous strata at several localities across southern and central Nevada and were partly joined by colleague Diana Boyer (Winthrop University) and her students.

In June, Silvi and Sam went on the department field trip to Greece and visited geological sites all over the country! They both continued on to the Goldschmidt geochemistry conference in Lyon, France, where Silvi presented her poster “The Role of Substrate and Seawater Geochemistry in Shaping the Fossilization of Earth’s Earliest Animal Communities.”

In July, Lidya and Sydney joined colleagues from Stanford (Erik Sperling and Emily Ellefson) and the Geological Survey of Canada (Keith Dewing) for an Arctic expedition to Bathurst Island, Nunavut to study Silurian-Devonian marine shales that capture geochemical conditions during the rise of early land plants. They collected hundreds of samples for a variety of geochemical analyses, saw a polar bear, and found plant fossils!

Last but not least, Kate’s undergraduate research was recently published in Palaeogeography, Palaeoclimatology, Palaeoecology! The title of her paper is “Appalachian Basin mercury enrichments during the Late Devonian Kellwasser Events and comparison to global records.” Link to the paper is here. Congratulations, Kate!