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Alycia Stigall

Alycia talks up brachiopods and running her paleontology lab on the Common Descent Podcast

I was recently a guest on the Common Descent podcast.  Will and David were really wonderful to talk with and had really great and insightful questions.  Our discussion was broad ranging and included brachiopods (of course), the Great Ordovician Biodiversification Event, running a paleontology lab, why my students are family to me, and running an international conference.

Spotlight – Alycia Stigall (3/5)

Welcome to our Spotlight Series! We’re talking paleo-science with some paleo-people! In this 5-part series, we’ve interviewed 5 different invertebrate paleontologists about their research and other work. In Episode 3, our guest is Dr. Alycia Stigall, shar…

Be sure to also check out the Common Descent interviews with lab alumni Adriane Lam and Ranjeev Epa!  Links here.

Ranjeev’s research on speciation in Tanzanian gastropods is published!

Ranjeev’s research on speciation in Tanzanian gastropods is published!

Congratulations to Ranjeev Epa (MS ’17)!  The research paper based on his MS thesis on systematics and morphology of Oligocene gastropods is now published in Papers in Paleontology.

Epa, Y.R., Stigall, A.L., Roberts, E.M., O’Brien, H., Stevens, N.J. 2018. Morphological diversification of ampullariid gastropods (Nsungwe Formation, late Oligocene, Rukwa Rift Basin) is coincident with onset of East African rifting. Papers in Palaeontology, 4:327-348.

Abstract:

A new freshwater gastropod fauna is described from the late Oligocene Nsungwe Formation of the Rukwa Rift Basin, Tanzania. Six new species of ampullariids are established including five species of Lanistes (L. microovum,L. nsungwensis, L. rukwaensis, L. songwellipticus and L. songweovum) and one species of Carnevalea (C. santiapillaii). These taxa occupy a morphospace region comparable to nearly half of extant Lanistes, a common and widespread genus in Africa and Madagascar. Palaeoecological evidence indicates that Nsungwe ampullariids inhabited fluvial, pond and paludal environments. Among these species are the oldest high‐spired and fluvially adapated Lanistes taxa. We suggest that Nsungwe Lanistes rapidly diversified in concert with habitat heterogeneity associated with the initiation of rifting along the western branch of the East African Rift System (EARS). Taxonomy, evolution and the biogeographical affinities of Nsungwe Formation freshwater gastropods contributes significantly to expanding the undersampled Palaeogene invertebrate fossil record of continental Africa.

 

Here is the university writeup about Ranjeev’s paper:

Paleontologists Find New Snail Species with Evolutionary Speed – Ohio University | College of Arts & Sciences

Snails may be physically rather slow, but the six new species identified by Ohio University researchers put on plenty of evolutionary speed when they had to. Ohio University paleontologists analyzing snail fossils from 24 to 26 million years ago have identified six new species-and published the first documentation of rapid …

 

Nilmani’s study of Ames Limestone Paleocommunities is published!

Nilmani’s study of Ames Limestone Paleocommunities is published!
So many beautiful brachiopods

Congratulations to Nilmani Perera (MS ’17)!  Her thesis project, which identified hierarchical biogeographic patterns in the paleo communities of the Pennsylvanian Ames Limestone has been published in Palaeogeography, Palaeoclimatology, Palaeoecology.

Perera, S.N. and Stigall, A.L. 2018. Identifying hierarchical spatial patterns within paleocommunities: An example from the Late Pennsylvanian Ames Limestone of the Appalachian basin. Palaeogeography, Palaeoclimatology, Palaeoecology, 506:1-11.

Abstract: Identifying ecological mechanisms that produce hierarchically arrayed spatial variation in community structure can be difficult in the fossil record due to conflation of spatial and temporal patterns. However, this difficulty can be mediated by minimizing the temporal duration of deposition within the unit examined. In this study, the fauna of the Upper Pennsylvanian Ames Limestone (Conemaugh Group) was analyzed to explore whether Ames paleocommunities exhibited hierarchical structure in a spatial dimension. This widespread carbonate unit was deposited during the maximum flooding interval of a glacio-eustatically influenced fifth order sea level cycle, and preserved taxa are contemporaneous within only a few thousand years. Paleocommunity structure and variability was assessed at multiple spatial scales using samples collected from seven outcrops of the Ames Limestone throughout southeastern Ohio which form a northeast to southwest trending transect parallel to the paleoshoreline. Abundance data were collected using quadrat sampling for brachiopods, bivalves, gastropods, bryozoa, corals, crinoids, echinoids, trilobites and foraminifera. Paleocommunity structure was analyzed via cluster, ordination, guild, and abundance analyses at multiple spatial scales (within a single locality, among localities and within the total study area) to provide insight on geographic partitioning of paleocommunity variation. Multiple levels of paleocommunity organization were recovered within the Ames fauna. All levels exhibited spatial partitioning, but the inferred proximate controls shifted from abiotic environmental controls at higher hierarchical levels to biotic controls at the lowest level. At the highest level, differentiation into a northern and southern regional paleocommunity was controlled primarily by substrate consistency and habitat heterogeneity related to variation in fluvial input within the basin. Local paleocommunity differentiation reflects biotic responses to topographic and environmental conditions that were geographically distributed within the region; whereas within outcrop variation was due largely to biotic feedback mechanisms.

Key points:

 

  • Paleoecology of a widespread, but temporally-restricted marine fauna was analyzed
  • Community analyses identified hierarchical constraints on spatial structure
  • Abiotic environmental controls were paramount at regional scales
  • Biotic interactions were primary at local scales
  • Hierarchical structure should be considered in paleocommunity analyses

 

Here is the university writeup about Nilmani’s paper:

Perera and Stigall Publish Study Detailing Ecological Structure of Local Fossil-Rich Limestone – Ohio University | College of Arts & Sciences

Generations of geology students at Ohio University have studied the Ames Limestone, the most fossiliferous rock layer in the Athens area, for class field trips and projects. This unit preserves skeletal remains of marine animals-corals, snails, brachiopods, trilobites, sharks- that inhabited a shallow sea that covered Athens about 300 million …

5th International Palaeontological Conference = Family trip to Europe!

by Alycia Stigall

The main meeting for me this summer was the International Paleontological Conference in Paris, from July 8-12th.  Dan and I typically attend the IPC meetings (prior conferences included IPC3 in London in 2010 and IPC4 in Mendoza, Argentina in 2014).  These are really broad international conferences with the potential to meet with international colleagues that we don’t see at the Annual GSA meetings.

Due to the timing of this year’s meeting, we decided to take our kids for their first European adventure.  So spent a week in Paris to attend the conference and explore then a week in the Swiss Alps. It was a really fantastic plan!  A very nice mix of European capitals and amazing nature.  The kids can’t wait to go back!

Here is a write up I did for Ohio University:

OHIO Paleontologists Stigall, Hembree Present in Paris – Ohio University | College of Arts & Sciences

Ohio University paleontologists Drs. Alycia Stigall and Daniel Hembree, both professors of Geological Sciences, presented at the 5th International Paleontological Congress in Paris (IPC5), France in July. The IPC5 is the largest gathering of professional paleontologists globally, and this meeting included more than 1,000 participants from around the world. All …

And some of my favorite photos:

IGCP 653 Synopsis and Photos

Here is my longer, formal report about all the exciting things that happened as part of the IGCP 653 meeting.

Annual meeting synopsis and photos | IGCP 653

The main Annual Meeting of the IGCP 653, titled “Trekking Across the GOBE (Great Ordovician Biodiversification Event): From the Cambrian through the Katian”, was a great success. The main meeting on the Ohio University campus, brought together a group of 60 scientists from eight nations. Read the Ohio University writeup here.

 

IGCP 653 Annual Conference

In my role as co-leader of the IGCP 653 project, I have a variety of jobs.  One is the social media/website/communications/membership director for the project.  Another is to convene occasional symposia at meetings, like this one that I co-led with Rebecca Freeman at 2017 Annual GSA meeting in Denver.  The most significant role so far, however, has been to organize the IGCP 653 Annual Meeting at my home institution, Ohio University.

Planning an international conference is a complex endeavor, and I spent substantial amount of the 2017-2108 academic year planning everything from the meeting website, meeting rooms, banquets, housing, arranging catering, acquiring grant support, printing name tags, producing the abstract volume, developing shuttle schedules to move participants from the Columbus airport to Athens, identifying volunteers to run field excursions, and then helping them with logistics, plus managing the finances of the entire system.  Needless to say, it was a tremendous effort, and the support of my co-organizers (especially Dan Hembree!) and the students workers during the meeting week was critical to success.

Overall, the meeting went very well.  We welcomed over 60 scientists from 8 countries to Athens.  The pre-conference excursion to the late Cambrian through Middle Ordovician strata of Great Basin of Utah and Nevada was spectacular, and the mid- and post-conference excursions to Kentucky were outstanding.  Everyone went home with plenty of brachiopods–and some other fossils, perhaps–and a greatly improved understanding of the stratigraphy, geochemistry, paleontology, and other facets of the Great Ordovician Biodiversification Event.

It was extremely rewarding to welcome my colleagues to campus after months of planning.  I learned a great deal in the process and was able to get to know some amazing people much better than I otherwise would have if it wasn’t my meeting.  However, I will also be very pleased to be an attendee and not an organizer for the foreseeable future.

Geological Sciences Hosts International Conference on Campus – Ohio University | College of Arts & Sciences

Ohio University hosted the Third Annual Meeting of the International Geoscience Programme (IGCP) 653 in June. This conference, titled “Trekking Across the GOBE (Great Ordovician Biodiversification Event): From the Cambrian through the Katian” brought together a group of 60 scientists from eight nations. Participants engaged in three days of scientific …

 

 

Women in Science Panel

by Alycia Stigall

I recently participated in a panel for a Women in Science class (PBIO 2170) on campus.  The students had very well considered questions, and the answers of the other panelists were very illuminating as well.

Women in Science Share Research Experiences, Career Insights – Ohio University | College of Arts & Sciences

A panel of Ohio University researchers made their love for science, math and engineering clear as they shared their scientific expertise and career insights with a Women in Science class on April 12. The class is made up of freshmen through seniors representing colleges across Ohio University. In groups composed …

 

Stigall profiled in FOSSIL Project Newsletter

I was recently interviewed for the FOSSIL Project Spring Newsletter.  The conversation was largely focused on how I became a paleontologist, my favorite things about paleontology, my passion for outreach and education, and advice for young people considering a career in science.

You can read the online version (which looks nicer) at this link: https://www.myfossil.org/featured-professional-alycia-stigall/

A PDF version is available here

 

 

Two new publications on the Great Ordovician Biodiversification Event

Hot off the presses!  

The Stigall Lab has two new articles published in the Lethaia special issue “Contextualizing the Great Ordovician Biodiversificaiton Event”. This special issue derives from the IGCP 653 opening meeting in Durham in October 2016, and includes papers on many aspects of the GOBE and related topics.  You can access the entire issue online here.

Our lab has two contributions:

Stigall, A.L. 2018. How is biodiversity produced? Examining speciation processes during the Great Ordovician Biodiversification Event. Lethaia, 51 (2), 165-172. https://doi.org/10.1111/let.12232.

–In this paper, I make the case that it is critical to consider biological aspects of speciation, not only aggregate diversity counts, when seeking the causes of diversification events, such as the GOBE.

Trubovitz, S., & Stigall, A.L. 2018. Ecological revolution of Oklahoma’s rhynchonelliform brachiopod fauna during the Great Ordovician Biodiversification Event. Lethaia, 51(2), 277-285. https://doi.org/10.1111/let.12233.

–This is the second half of Sarah Trubovitz MS thesis, which examines community structure and body size in brachiopod communities across the GOBE in the Simpson Group of Oklahoma.

IGCP 653 Field excursion and workshop on the Fezouata Formation

by Alycia Stigall
IGCP 653 Field excursion and workshop on the Fezouata Formation

I was very fortunate to attend the IGCP Project 653  outstanding workshop and field excursion in Marrakech and Zagora region of Morocco from February 12-16, 2018.

This was a fantastic trip!  Morocco is a fantastic country with amazing geology and really wonderful people.  The Fezouata outcrops were really tremendous, and I was able to collect some specimens for my teaching collection as well.

Click here to read my write up and visit photo galleries that I posted as the media czar for the IGCP project. A few bonus photos are below.