Modern animal life could have arisen in a storm-dominated deltaic environment

Our understanding of how and where the ancestors of modern life evolved has been the question of many paleontologists for a long time. Recently, an international team of sedimentologists and paleontologists, including Dr. Luis Buatois, Dr. Gabriela Mángano, and Dr. Maximiliano Paz, demonstrated that a world-famous Cambrian soft-bodied fossil assemblage in Yunnan province, China, lived and died in a delta front environment affected by storms. The Chengjiang Biota records the exquisite preservation of soft-bodied marine invertebrates, including worms, early arthropods, and early vertebrates. This assemblage is around 518 million years old, around the time of the famous Cambrian explosion, where modern communities of animals first started to truly diversify. The Chenjiang biota has a similar faunal makeup to the Burgess Shale biota from British Columbia, Canada. The team analyzed a core taken from Cambrian outcrops in Yunnan, China, and discovered that the sequence of strata was formed in a shallow marine, deltaic environment. High rates of sedimentation and indications of high salinity point to this deltaic environment being dominated by storms and river floods. These kinds of sediments help us to understand the exceptional taphonomy of fossils from these Cambrian assemblages.

Figure. Block diagram showing the storm-flood-dominated delta and associated cores showing depositional sequences. (From F. Saleh et al., 2022)

The full article can be accessed in Nature Communications.

Written by Jack Milligan

Dr. Anthony Shillito receives Banting Postdoctoral Fellowship to conduct research at USask on animal aquatic-terrestrial transition

Dr. Anthony Shillito from the University of Oxford, England, is one of the recent recipients of the Banting Postdoctoral Fellowship, which allows exceptional scholars to continue their research with the help of federal funding.

Dr. Shillito’s project at the University of Saskatchewan will be focused on understanding why animals began the transition from marine to terrestrial, and the factors that may have played a part in establishing terrestrial faunal communities. He has previously conducted fieldwork looking into this research question in places such as the United Kingdom, Australia, and the Canadian Arctic. His work will look at this transition through the perspective of the trace fossil record including burrows and trackways, including analysis of the sedimentology associated with these important fossils. Congratulations on receiving this prestigious award Anthony, we are excited to have you join our research group!

You can read more of Dr. Shillito’s research on his ResearchGate page!

Written by Jack Milligan

Dr. Mángano named Distinguished Professor at USask

We are excited to share that our own Dr. Gabriela Mángano has been named a distinguished professor by the University of Saskatchewan Distinguished Professorship Advisory Committee.

She was recognized for her breadth of contributions in the areas of ichnologic and sedimentological research on an international scale. She has mentored and supervised many students, many of whom are underrepresented in the geosciences, including women and minority groups. Congratulations Gabriela on this amazing achievement!

She also received the award for Outstanding Educator Award from the Association for Women Geoscientists back in 2018.

Written by Jack Milligan

Dr. Buatois recipient of the 2022 Raymond C. Moore Medal for Paleontology by SEPM

We are thrilled to share that Dr. Luis Buatois has received the 2022 Raymond C. Moore Medal for Paleontology from the Society for Sedimentary Geology. This prestigious international award recognizes accomplished researchers who have contributed a great amount to the field of paleontology (see SEPM interview on YouTube).

Today, Dr. Buatois is regarded as one of the world’s renowned experts on animal trace fossils, and the early history of life on Earth through the lens and framework of ichnology. He supervises a large group of students and serves on editorial boards for geological and paleontological journals. From all of us at Ichnoplanet, congratulations Luis!

Written by Jack Milligan

Associated Champsosaur skeleton in Southwest Saskatchewan discovered by Jack Miligan

Following the K-Pg mass extinction event which wiped out the non-avian dinosaurs, the swamps and floodplains of southwest Saskatchewan were populated by an assortment of small to medium sized vertebrates including turtles, crocodiles, early mammals, and a now-extinct group of semi-aquatic reptiles known as champsosaurs. During a joint research expedition near the town of Climax, Saskatchewan by the Royal Saskatchewan Museum and Carleton University in Ottawa in August 2020, an associated skeleton of a champsosaur was recovered by Jack Miligan. The champsosaur was collected in a terrestrial shale horizon around 3 m above the K-Pg boundary, from the Paleocene aged Grey Facies of the Ravenscrag Formation. The Grey Facies records a low energy, vegetated swamp environment. 

Champsosaur hind foot (middle right in image). Photo by Jack Miligan.

This skeleton is between 35-40% complete and is comprised of several dorsal and caudal vertebrae with intact neural arches and transverse processes, incomplete bones from all four limbs including a humerus and femurs, dozens of ribs, and several elements making up the pectoral and pelvic girdles. Numerous gastralia as well as a near complete hind foot were found in-situ upon examination of the shale horizon from which the bones had eroded out of. More fieldwork is needed to try and recover cranial material to affirm an accurate taxonomic identification of this specimen.

Research into the osteology of the specimen, as well as a review of the paleoecology of the vertebrate fauna of the Ravenscrag Formation is underway and could yield new insight into biostratigraphy, and macroevolutionary trends of champsosaur species across the K-Pg boundary in Saskatchewan.

You can read more about the discovery in this Usask news article.

Written by Jack Miligan

Note: Jack recently joined the ichnofamily at Usask as an M.Sc. student! You can read more about him on his ichnoplanet profile, or follow him on ResearchGate or Twitter. –Brittany