Evolution of land plants from their algal ancestors • Precambrian terrestrial ecosystems • Fossil origins of complex multicellularity
News and Views:
update: September 21, 2023
The Linnaean Society Palæobotanical Specialist Group will meet at Burlington House in Piccadilly, London, November 22, 2023, followed by
the Palynology Specialist Group the following day, November 23.
now published. Green Land: Multiple perspectives on green algal evolution and the earliest land plants, American journal of Botany 110(5) May 2023 e16175, is available for download as open access, https://doi.org/10.1002/ajb2.16175. This review is somewhat interesting as it looks at terrestrial green algae and the origin of land plants from several completely different viewpoints, from molecular phylogenomics to classical phycology.
The 14th International Symposium on the Ordovician System. An extended abstract of the keynote presentation, "An evo-devo perspective on no Ordovician land plants," has been published in the Estonian Journal of Earth Sciences.
November 10, 2022. Sixth International Palaeontological Congress this November 7 - 11 in Khon Kaen, Thailand. Session #22 The origin of a land flora: from Laurentia to Gondwana and back again. The keynote presentation, On the Fossil Origin of Plant Development, is available for download as a pptx file.
August 2021. A discovery of Lower Ordovician cryptospores from the Nambeet Formation in the Canning Basin of Western Australia, A fossil record of land plant origins from charophyte algae, was published August 13th in the journal Science. This report, which is the result of a collaboration with Clinton Foster at the Australian National University in Canberra, helps connect the fossil record of Cambrian cryptospores with younger land plant spores and establishes cryptospore dyads as important players in tracking the origins of plant development. For more information, For more on this story please see Clinton Foster’s article in The Conversation, or the Science Perspective written by Patricia Gensel at UNC.
Official BC Press Release about the discovery, by Ed Hayward.
More about cryptospores from the Nambeet Formation including links to the abstract, reprints and full text.
June 2021. Work on microfossils of the Torridonian Sequence in Northwest Scotland continues with the recent publication of, A possible billion-year-old Holozoan with differentiated multicellularity, in the journal Current Biology. You can find more information about this early example of complex multicellularity in biology, Bicellum Brasieri on this local webpage. There are now more than a hundred on-line news posts world-wide about this fossil, if you are interested, just enter "Bicellum" in any search engine. Bicellum brasieri even has its own Wikipedia entry.
Official BC Press Release about the discovery.
The Grand Canyon
Since 1996, ongoing collecting in the Tonto Group (middle Cambrian) of the eastern Grand Canyon has recovered assemblages of non-marine microfossils, including some important records of early cryptospores. The Bright Angel Shale, long thought to represent a classic transgressive marine shale, is more likely estuarine, and clearly close to land, as evidenced by scree-covered debris seen below on Utah Flats in the eastern Grand Canyon.
Photo - L. van Maldegem
This work has expanded to include a trip in 2014 to the Nankoweap Butte with European colleagues (above) collecting biomarker samples with Pierre Sansjofre and Chris Hallmann in Neoproterozoic shales of the Chuar Group. The initial results of this research were published in 2019 in Nature Communications.
The Torridonian Sequence of the Northwest Scottish Highlands
Together with Charles Wellman (Sheffield University) we have been collecting organic-rich shales and phosphatic nodules from Torridonian rocks since 2008. Most of our work is focused on documenting microfossils extracted via acid maceration (palynology) but in 2011 we teamed up with Martin Brasier's group at Oxford University to summarize the micropaleontology of the entire sequence in, The Earth's Earliest non-marine Eukaryotes. which was published in Nature in 2011. That collaboration continues with the discovery of a probable early holozan, Bicellum Brasieri named in honor of the late Martin Brasier.
Palynology of the Triassic-Jurassic Boundary
Bas van de Schootbrugge and I discovered what at first we thought were moth scales in a boundary core from north Germany. With the assistance of Torsten Wappler, Henk Visscher, and others, Timo van Eldijk, from Utrecht University, was able to determine the affinity of these scales. See our article, "A Triassic-Jurassic window into the evolution of Lepidoptera" in Science Advances. Recent work on these same deposits show evidence of soil erosion after the extinction boundary, see van de Schootbrugge et al. 2020. Earth-Science Reviews.
Early Lepidopterid scale