Earth Science Club of Northern Illinois - ESCONI

Video for ESCONI Paleontology Meeting November 2024 - "Devonian Fossils From Independence" #fossils #paleontology #cephalopods #iowa #devonian

The ESCONI Paleontology Study Group Meeting for November 2024 featured an interesting presentation by Jim Preslicka. His presentation was titled "Devonian Fossils From Independence". Jim has a deep interest in cephalopods. The eastern Iowan deposit was discovered by the Blackhawk Gem and Mineral Society in 2007. A joint project between the BHGMS and the University of Iowa's Paleontology Repository have uncovered many new and rare cephalopods at the locality.

Video for ESCONI General Meeting November 2024 - "From Muldraugh to Museum: Amphoracrinus tenax" #fossils #paleontology #crinoids #kentucky

The topic of the November 2024 Paleontology meeting was "From Muldraugh to Museum: The Unexpected Journey of Crinoid Amphoracrinus tenax". It was presented by ESCONI member Gretel Monreal. This presentation will include the investigative process for recognizing a new species of crinoid and explaining what this simple fossil can tell us. 

Amphoracrinus tenax was described in a paper published in the Journal of Paleontology.

Abstract

The youngest species of Amphoracrinus, A. tenax new species, is described from the Muldraugh Member of the Borden Formation (early Viséan) of north-central Kentucky. With this new occurrence, both the oldest and youngest named species of Amphoracrinus are from North America. Numerous Tournaisian and Viséan crinoid faunas are documented in the United States, but only four are known to contain Amphoracrinus. Morphological analysis indicates that A. tenax is more closely aligned with species from China than with species from Western Europe or other species from North America, where Amphoracrinus was most diverse and abundant, which has implications for understanding paleogeographic dispersal. The holotype of A. tenax was partially disarticulated on the seafloor before burial, and final burial occurred early during disarticulation. The relative state of disarticulation from pinnules to columnals suggests that plates bound only with ligaments disarticulated as a function of surface area of ligaments binding an articulation.

 

Video for ESCONI June 2024 General Meeting - “A North American fossil primate called Ekgmowechashala” #fossil #paleontology #fossils

The June 2024 General Meeting was held on June 14th, 2024 via Zoom.  Kathleen Rust of the University of Kansas spoke about Ekgmowechashala, a primate known only from the late early Oligocene of western North America.

"I am planning on presenting findings from my most recent publication describing a new primate species from the late Eocene of China that we named Palaeohodites and how its discovery elucidates the origin of a very funky primate species from the Oligocene of North America called Ekgmowechashala. My talk is about 30-40 mins. I will most certainly make time for questions from the audience."

Here's a link to an an article about her recent paper on the subject.

Fossils tell tale of last primate to inhabit North America before humans

The story of Ekgmowechashala, the final primate to inhabit North America before Homo sapiens or Clovis people, reads like a spaghetti western: A grizzled and mysterious loner, against the odds, ekes out an existence on the American Plains.

Except this tale unfolded about 30 million years ago, just after the Eocene-Oligocene transition during which North America saw great cooling and drying, making the continent less hospitable to warmth-loving primates.

Today, paleontologists from the University of Kansas and the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing have published evidence in the Journal of Human Evolution shedding light on the long-standing saga of Ekgmowechashala, based on fossil teeth and jaws found in both Nebraska and China.

Phylogeny and paleobiogeography of the enigmatic North American primate Ekgmowechashala illuminated by new fossils from Nebraska (USA) and Guangxi Zhuang Autonomous Region (China)

Abstract

Ekgmowechashala is a poorly documented but very distinctive primate known only from the late early Oligocene (early Arikareean) of western North America. Because of its highly autapomorphous dentition and spatiotemporal isolation, the phylogenetic and biogeographic affinities of Ekgmowechashala have long been debated. Here, we describe the oldest known fossils of Ekgmowechashala from the Brown Siltstone Beds of the Brule Formation, White River Group of western Nebraska. We also describe a new ekgmowechashaline taxon from the Nadu Formation (late Eocene) in the Baise Basin of Guangxi Zhuang Autonomous Region in southern China. Phylogenetic analysis suggests that North American  Ekgmowechashala and the new Chinese taxon are sister taxa that are nested within a radiation of southern Asian adapiforms that also includes Gatanthropus,  Muangthanhinius, and Bugtilemur. The new Chinese ekgmowechashaline helps fill the considerable disparity in dental morphology between Ekgmowechashala and more primitive ekgmowechashalids known from southern Asia. Our study underscores the fundamental role of southern Asia as a refugium for multiple primate clades during the cooler and drier climatic regime that prevailed after the Eocene–Oligocene transition. The colonization of North America by Ekgmowechashala helps define the beginning of the Arikareean Land Mammal Age and corresponds to an example of the Lazarus effect, whereby a taxon (in this case, the order Primates) reappears suddenly in the fossil record after a lengthy hiatus.

Video for ESCONI May 2024 Paleontology Meeting - "The Upper Ordovician Platteville Formation" #fossils #paleontology #geology #platteville #northernillinois

The May 2024 Paleontology Study Group meeting was held on Saturday, May 18th, 2024. John Catalani did a presentation about the Upper Ordovician Platteville Formation here in northern Illinois and southern Wisconsin. He details the name changes how it relates to the surrounding area.

Video for ESCONI April 2024 Paleontology Meeting - "Terror Birds"

The April 2024 was held on April 20th, 2024 at 7:30 via Zoom.  The presenter was ESCONI member John Catalani.

Abstract

We begin with an explanation of the “Terror Birds” and their position in Geologic Time. The two major groups of these large cursorial birds are the Phorusrhacidae and the Gastornithidae. The first group was the longest lasting and, until the very end, lived in South America, at that time an isolated continent. With the appearance of the Panamanian Land Bridge and the Great American Biotic Interchange, the last “Terror Bird” took up residence in the, mostly, southeastern United States. The Interchange is also believed to have been the cause of the eventual extinction of the Phorusrhacidae. The Gastornithids, inhabiting Europe and North America, did not exist as long as the Phorusrhacids becoming extinct for unknown reasons mid-Eocene. This group consisted primarily of Diatryma in North America and Gastornis in Europe. Detailed study has determined that the two birds were actually congeneric. We will survey both groups for habitats and significant species with bird skeletal features and restorations illustrating the talk.

Video for ESCONI April 2024 General Meeting - "Ice age mammals from the frozen North” #fossils #paleontology #arctic #alaska #iceage #mammals

The ESCONI General Meeting for April 2024 was held on Friday, April 12th, 2024 at 8:00 PM zia Zoom.  The topic of the presentation is "Ice age mammals from the frozen North".  It was given by Yukon Paleontologist Grant Zazula.

Ever since the Klondike Gold Rush of 1898, Yukon miners in search of shiny gold nuggets have uncovered the spectacular remains of ice age mammals. This presentation will feature the phenomenal record of ice age mammals and paleo-environments recovered in the wilds of northwest Canada, including spectacular permafrost preserved animal mummies. Collaboration between gold miners, local First Nations communities and scientists highlights how we work together to understand the past.

Video for ESCONI February 2024 - General Meeting, Topic: “Photographing Rock Art in Illinois and Missouri: A visual journey into the sacred, the unknown, and the creation of the universe” #archaeology #nativeamerican #art #history

The ESCONI February 2024 General Meeting was held on Friday, February 9th, 2024.  The topic was “Photographing Rock Art in Illinois and Missouri: A visual journey into the sacred, the unknown, and the creation of the universe”.  It was presented by Mike Chervinko. Mike is author of "Prehistoric and Natural Wonders of Southern Illinois".   The video is available on Youtube.

When people think about Illinois, what usually comes to mind are cornfields, flat prairies, and Chicago. It’s hard to blame them because, for the most part, they’re right. However, the prairie state does hold a few surprises. Many of these surprises can be found in the southern 10% of the state. It is there the glaciers stopped and spared what is now a hidden gem of natural beauty and prehistoric interest. It is the aim of this book to show people some of these magical places and things that are unique to southern Illinois – my backyard. This edition combines over 350 of my photographs with essays and personal accounts to provide a surprising, and inspiring, overview of some of southern Illinois' most popular natural destinations and best keep secrets.

Video for ESCONI December 2023 General Meeting - "Ancient Forest Pests: Plant-Insect Interactions in the Fossil Record” #paleontology #fossil #evolution #fossils #paleobotany #plants #insects

The December 8, 2023 General Meeting presentation was held via Zoom.  It was presented by Michael Donovan, Collections Manager, Paleobotany at the Field Museum will present "Ancient Forest Pests: Plant-Insect Interactions in the Fossil Record".

 

Plants and insects are the most diverse multicellular organisms on Earth, and their abundant interactions are fundamental components of ecosystems on land. Plant-feeding insects are highly sensitive to environmental disturbances, including past extinction events and climate change. In this talk, I will discuss my research examining how major environmental changes affected ancient insect and plant biodiversity and biogeography, and how those changes have shaped modern ecosystems.

Video for ESCONI Paleontology Meeting November 2023 #fossils #paleontology #germany #jurassic #solnhofen #lagerstatte #archaeopteryx

The presentation at the November 2023 Paleontology Meeting was given by Bruce and Rene Lauer. The title of the talk was "A Snapshot in Time: The Jurassic Lagerstätte of the Solnhofen Archipelago, Germany".

Bruce and Rene Lauer are founders and administrators of the Lauer Foundation for Paleontology, Science, and Education.

The Lauer Foundation for Paleontology, Science and Education (PSE) is passionate about promoting the cooperation and collaboration between scientists, individuals and commercial fossil collectors for the advancement of science.  The Lauer Foundation PSE is an active operating foundation and the Foundation's collections are curated using museum standards including the Specify Software, collection management system, and storage of specimens in a museum grade climate controlled environment.  The Foundation adheres to responsible acquisition practices, requiring proper provenance for additions to the Foundation collections.  The Foundation actively participates in the study, analysis, documentation and research of its fossil collections with the international scientific community. 

 

Video for ESCONI October 2023 General Meeting - "Microfossils to Mosasaurs: A Journey Through the University of Iowa Paleontology Repository” #paleontology #fossil #evolution #iowa

Here is the video for the October 2023 General Meeting.  The speaker was Tiffany Adrain, who works as the Paleontology Repository Collections Manager at the University of Iowa.  The topic of her presentation was “Microfossils to Mosasaurs: A Journey Through the University of Iowa Paleontology Repository”. 

 

Video for ESCONI June 2023 General Meeting - "Using geophysics to capture Earth burps and other processes during flow through karst conduits” #karst #geology #geophysics

The topic for the ESCONI June 2023 General Meeting was "Using geophysics to capture Earth burps and other processes during flow through karst conduits".  Our speaker was Andrew Luhmann Assistant Professor of Geology in the  Department of Earth and Environmental Science, Wheaton College, in Wheaton, IL.

Karst aquifers are important water resources that are susceptible to contamination from land surface activities. Traditional monitoring strategies rely on spring and well sampling to learn about these flow systems, but we are using geophysics to understand the karst aquifer architecture, including the conduits where much of the flow occurs through these systems as well as the relevant processes that happen within them. During a pilot study in a karst aquifer in Minnesota, we monitored seismic responses during water injection experiments and following a large rainfall event, which caused a discharge increase at Bear Spring and ground motion that originated from multiple source locations. Based on observations and calculations, we suggest that the largest signals resulted from the release of overpressurized air pockets in karst conduits as water levels were rising, where energy was released as the pressurized air encountered pathways to escape from the conduits. Furthermore, we monitored seismic and tilt responses over a three-year period at the Santa Fe River Sink-Rise flow system in Florida, where water flows through conduits 20 m in diameter that are 30 m below the surface. Our modeling efforts have shown that water pressure changes in the conduits cause land surface displacement and tilt, and that this may provide information on conduit location and size. Geophysical tools enable monitoring of fundamental flow processes and dynamics beyond what is possible with traditional monitoring strategies, and our ongoing research is trying to use this information to better characterize the subsurface, identify karst conduits, and monitor for subsurface flow.

 

Video for ESCONI May 2023 General Meeting - "About the Falls of the Ohio State Park” #fossil #paleontology #devonian

The title of the presentation at the May 2023 General Meeting was "About the Falls of the Ohio State Park".  It was given by Dr. Alan Goldstein.

As a Park Paleontologist and Interpretive naturalist, Dr. Goldstein has worked at the Falls of the Ohio State Park's Interpretive Center since it opened in January 1994.

Additionally, Dr. Goldstein has also been the curator of the Gerald Troost collection at the Louisville Science Center. He has been investigating, collecting, and writing about the Illinois-Kentucky fluorspar district since 1982. His article on the fluorspar district published in 1997 won the Friends of Mineralogy paper of the year. He has also written for Mineral News and contributed to the American Mineral Treasures volume. He has published over 130 articles in periodicals including two that won national peer awards. In addition to his professional writing, he has also published the novel “The Dragon in My Back Yard”.

Additional Information

Rugose corals, Horn shapes, Fossils, Kentucky Geological Survey, University of Kentucky (uky.edu)

Curating — Mobile Rock & Gem Society (mobilerockandgem.com)

Falls of the Ohio State Park - Birding/ Birdwatching Opportunities – Indianabirdingtrail

Posts by Alan Goldstein | Leisure and Travel Blog (gosoin.com)

2016 Speaker Alan Goldstein « Dallas Mineral Symposium (dallassymposium.org)

https://alangoldsteinsuniverse.com/my-story/

https://www.courier-journal.com/story/entertainment/books/2021/07/22/dragon-in-my-backyard-written-by-louisville-naturalist-alan-goldstein/5350656001/

The Dragon in my Back Yard: Goldstein, Alan: 9798520230205: Amazon.com: Books

Video for ESCONI Paleontology Meeting January 2023 "The Devonian Period" #fossil #paleontology ##devonian #deeptime

The ESCONI Paleontology Sttudy Group Meeting was held on Saturday, January 21st, 2023. The topic was "The Devonian Period". The presentation was given by ESCONI member and Field Trip Chairman John Catalani.

Palaeogeographic map of the Late Devonian world, based on ref.77. The location of Steinbruch Schmidt(1), the Siljan impact crater (S), the Viluy Traps (V), and the Kola, Vyatka, and Pripyat–Dniepr–Donets rift systems (K-V-PDD) are indicated.

Video for ESCONI February 2023 General Meeting - “Baby Dinosaurs of the Arctic: Discovery and Research of a Dinosaur Nursery North of the ” #fossil #paleontology #fossils #dinosaur #alaska #cretaceous

The February 2023 General Meeting was held on February 10th. The program “Baby Dinosaurs of the Arctic: Discovery and Research of a Dinosaur Nursery north of the Arctic Circle” was presented by Dr. Patrick Druckenmiller.

Dr. Druckenmiller is Professor of Geology and Director of the University of Alaska Museum of the North. He is a vertebrate paleontologist who research encompasses Mesozoic marine reptiles and Alaskan dinosaurs. He has conducted extensive fieldwork in North America and the Arctic, including northern Alaska where he directs excavation of the northernmost dinosaurs to ever walk the Earth.

He became the Earth Sciences Curator in 2007 after moving up from Montana. Dr. Druckenmiller has conducted paleontological fieldwork across much of the western US and Canada and has active field sites across Alaska, including the southeastern panhandle, the Alaska Peninsula, the North Slope, and several locations in between.

Patrick received his PhD from the University of Calgary, Alberta, Canada. His dissertation: Early Cretaceous plesiosaurs (Sauropterygia: Plesiosauria) from northern Alberta: palaeoenvironmental and systematic implications.

Further information sent in by long time ESCONI member Donald Baumgartner.  Thanks, Don!

(James Havens; Patrick Druckenmiller)

https://www.amazon.com/Arctic-Dinosaurs-Alaska-Bonnye-Matthews/dp/195489600X

 

https://www.sciencedirect.com/science/article/pii/S0960982221007399?via%3Dihub

https://www.theguardian.com/science/2021/jun/24/dinosaur-fossils-eggs-arctic-research

https://www.newscientist.com/article/2282122-dinosaurs-lived-in-the-arctic-around-70-million-years-ago/

https://www.sciencealert.com/the-ancient-arctic-was-a-haven-for-dinosaurs-and-their-babies

 

 

Video for ESCONI January 2023 General Meeting - “New Evidence for Cretaceous Ornithomimosaurs (dinosaurs) from Mississippi” #fossil #paleontology #fossils #dinosaur #mississippi #cretaceous #ornithomimosaurs

The speaker at our meeting (via Zoom) on the evening of January 13, 2023 was Dr. Thomas Cullen. He is currently a postdoc at Carleton University in Ottawa, Ontario. The topic of his talk was "New evidence for large ornithomimosaurs in the Southeastern US and the biogeography of Cretaceous ostrich-mimic dinosaurs".

Here is a link to the article on this material, published in October 2022. It is open access:

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0266648

 

 

Abstract

 

Reconstructing the evolution, diversity, and paleobiogeography of North America’s Late Cretaceous dinosaur assemblages require spatiotemporally contiguous data; however, there remains a spatial and temporal disparity in dinosaur data on the continent. The rarity of vertebrate-bearing sedimentary deposits representing Turonian–Santonian ecosystems, and the relatively sparse record of dinosaurs from the eastern portion of the continent, present persistent challenges for studies of North American dinosaur evolution. Here we describe an assemblage of ornithomimosaurian materials from the Santonian Eutaw Formation of Mississippi. Morphological data coupled with osteohistological growth markers suggest the presence of two taxa of different body sizes, including one of the largest ornithomimosaurians known worldwide. The regression predicts a femoral circumference and a body mass of the Eutaw individuals similar to or greater than that of large-bodied ornithomimosaurs, Beishanlong grandis, and Gallimimus bullatus. The paleoosteohistology of MMNS VP-6332 demonstrates that the individual was at least ten years of age (similar to B. grandis [~375 kg, 13–14 years old at death]). Additional pedal elements share some intriguing features with ornithomimosaurs, yet suggest a larger-body size closer to Deinocheirus mirificus. The presence of a large-bodied ornithomimosaur in this region during this time is consistent with the relatively recent discoveries of early-diverging, large-bodied ornithomimosaurs from mid-Cretaceous strata of Laurasia (Arkansaurus fridayi and B. grandis). The smaller Eutaw taxon is represented by a tibia preserving seven growth cycles, with osteohistological indicators of decreasing growth, yet belongs to an individual approaching somatic maturity, suggesting the co-existence of medium- and large-bodied ornithomimosaur taxa during the Late Cretaceous Santonian of North America. The Eutaw ornithomimosaur materials provide key information on the diversity and distribution of North American ornithomimosaurs and Appalachian dinosaurs and fit with broader evidence of multiple cohabiting species of ornithomimosaurian dinosaurs in Late Cretaceous ecosystems of Laurasia.

Video for ESCONI November 2022 General Meeting - “A Sea Without Fish, Ordovician Fossils of the Cincinnati Region” #fossil #paleontology #ordovician #cincinnati #ohio #indiana #fossils

For the November 2022 General Meeting, our speaker was Dr. David Meyer from the University of Cincinnati. The title of his talk was "A Sea Without Fish, Ordovician fossils of the Cincinnati region".  His book has the same name as his presentation.  Checkout his page at the University of Cincinnati.

Book Description:

The region around Cincinnati, Ohio, is known throughout the world for the abundant and beautiful fossils found in limestones and shales that were deposited as sediments on the sea floor during the Ordovician Period, about 450 million years ago-some 250 million years before the dinosaurs lived. In Ordovician time, the shallow sea that covered much of what is now the North American continent teemed with marine life. The Cincinnati area has yielded some of the world's most abundant and best-preserved fossils of invertebrate animals such as trilobites, bryozoans, brachiopods, molluscs, echinoderms, and graptolites. So famous are the Ordovician fossils and rocks of the Cincinnati region that geologists use the term "Cincinnatian" for strata of the same age all over North America. This book synthesizes more than 150 years of research on this fossil treasure-trove, describing and illustrating the fossils, the life habits of the animals represented, their communities, and living relatives, as well as the nature of the rock strata in which they are found and the environmental conditions of the ancient sea.

 

Video for the ESCONI December 2022 General Meeting - “The early diversification of birds: evidence from the Jehol avifauna” #fossil #paleontology #fossils #dinosaur @FieldMuseum @SUEtheTrex #birds #bird #video

December's General Meeting was held on December 2nd, 2022.  The presenter was Dr. Jingmai O’Connor Associate Curator of Fossil Reptiles at the Field Museum.  The topic of her talk was "The early diversification of birds: evidence from the Jehol avifauna".

She calls herself a paleontologista aka a punk rock paleontologist. 

Her research includes work on birds, dinosaurs, and the bird-dinosaur transition.  The following is an excerpt from her Field Museum Staff Profile.

Relatively speaking, my passion for paleontology developed late in life. I first became interested in evolution through Dr. Donald Prothero while a Geology major at Occidental College (Class of 2004). With his encouragement, I started volunteering in the Paleontology Department at the Los Angeles County Museum of Natural History (LA NHM) and conducted undergraduate research with their fossil mammal curator Dr. Xiaoming Wang. For my PhD, I started studying Mesozoic birds at the University of Southern California (Class of 2009) with Drs. David Bottjer (USC) and Luis Chiappe (LA NHM). After graduation, I moved to Beijing, China where I worked with Dr. Zhonghe Zhou at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) for nearly 11 years. I started as a postdoc and became their youngest full professor in 2015.

My research explores the evolution of flight in the Dinosauria, the dinosaur-bird transition, and the evolution of modern avian physiology, not through any one aspect but exploring Paraves (the group formed by birds and their closest non-avian dinosaurian relatives) through feather origin and function, aerodynamics, reproduction, respiration, diet, anatomy, systematics, ontogeny, taxonomy, histology, and other topics based on what we find preserved.

Thanks to the amazing fossils that I’ve been fortunate to study, my research has been published in Nature, Science, the Proceedings of the National Academy of Sciences (PNAS), and Current Biology, and in 2019 I was awarded the Schuchert Award for excellence in Paleontology under the age of 40 by the Paleontological Society.

I have conducted fieldwork in China, Mongolia, Romania, South Africa, Canada, and the United States, and I am looking forward to starting my own active field program based out of the Field Museum.

In addition to my curatorial duties at the Field Museum, I am a research associate at LA NHM and the American Museum of Natural History in New York, an adjunct professor at the IVPP, and I serve as an editorial board member for several journals.

I am passionate about helping others along their academic trajectory and sharing my research with audiences of all ages hoping to help inspire the next generation of scientists.

See her website for more information.

Video for the ESCONI September 2022 General Meeting - "Paleozoic fishes of the Illinois Basin” #fossil #paleontology #paleozoic #fish #fossils #illinois

The September 2022 General Meeting was held on Friday, September 9th, 2022.  The presenter was Dr. Ryan Shell of the Cincinnati Museum Center.  The title of his talk was "Paleozoic fishes of the Illinois Basin”.  Dr. Shell is a research associate in the department of vertebrate paleontology at the Cincinnati Museum Center and a Paleontological Resources Assistant at the United States Forest Service. He does research in paleontology, systematics, taxonomy, biostratigraphy and biogeography.

Topic: Paleozoic fishes of the Illinois Basin
Presented By: Dr. Ryan Shell

Mazon Monday #134: 2022 Mazon Creek Open House Report With Videos #MazonMonday #fossils #MazonCreek #paleontology #fossil

This is Mazon Monday post #134.  What's your favorite Mazon Creek fossil?  Tell us at email:[email protected].  Thanks!

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The 2022 Mazon Creek Open House was held on Saturday, October 15th, 2022 at Cantigny Park in Wheaton, IL.  It was a rousing success!  We had around 100 visitors throughout the day.  There was plenty to talk about as we had three display cases of fossils - two from the Field Museum, which included the holotype for Exessella asherae and one case of fossils from ESCONI members Keith Robitschek, Andy Jansen, and Rich Holm.

Here are a few random photos from the day.

We can release videos of three of the presentations today.  The presentation by Jason Pardo will be released after his research is published.

2022 Mazon Creek Open House - "The Tully Monster: Identity, Morphology, and Ecology". Presented by Victoria E. McCoy. University of Wisconson-Milwaukee.

2022 Mazon Creek Open House - "The Mazon Creek Cnidarian Essexella: The World Turned Upside Down". Presented by Roy E. Plotnick, Universiity of Illinois at Chicago

2022 Mazon Creek Open House - "Snapshot in time - Geologic Secrets of the Springfield Coal Fossilized Forests". Presented by Scott Elrick, Head of Coal, Bedrock Geology and Industrial Minerals Section - ISGS

 

Video for ESCONI April 2022 General Meeting - "Devonian plants from the famous Red Hill location” #fossil #paleontology #pennsylvania #devonian #plants #redhill

 

The April 2022 General Meeting was held on Friday, April 8th, 2022.  The presentation was "Seeing the Forest for the Fossil Trees - Plants at Red Hill" by Dr. Walt Cressler of West Chester University in Pennsylvania.

Red Hill is known for the First Modern Tree and a bunch of very early vertebrates.  For information about Red Hill plants, see this page at the Devonian Times.

The First Modern Tree

Archaeopteris spp. account for slightly more than half of the identifiable plant fossils collected at the floodplain pond facies of Red Hill; the pre-fern Rhacophyton accounted for most of the rest. Typically, these fossils were relatively intact abscised branches that were probably blown by the wind into the floodplain pond from elsewhere in the floodplain. Larger woody fossils (i.e., trunks or large branches) have yet to be collected, but one likely and several suggestive root casts have been found. The fossils collected at Red Hill are assignable to four species based on leaf morphology. Most belong to either Archaeopteris macilenta or A. hibernica. Two other species, A. halliana and A. obtusa, were much less frequent.

The co-dominance of Archaeopteris and Rhacophyton at Red Hill is typical of Late Devonian floodplain localities from the Catskill Delta (New York, Pennsylvania, Virginia, West Virginia). Archaeopteris was also common to abundant in some near-marine Catskill localities, primarily as sea-drifted logs (form genus Callixylon). In addition, Archaeopteris-dominated forests are common in Late Devonian localities from elsewhere in Euramerica (North America and Western Europe), Gondwana (Africa, Antarctica, Australia and South America), China and Siberia. It has been found at paleolatitudes ranging from equatorial to sub-polar. From its first appearance in the middle Frasnian Archaeopteris quickly became an important and typically dominant component of the flora. Indeed, it became the lynchpin of the first true forests. Archaeopteris remained paramount until the end of the Devonian, at which time it mysteriously became extinct.

Fossil of Archaeopteris halliana. Photo courtesy of Walt Cressler.