NDLI: Resistant tissues of modern marchantioid liverworts resemble enigmatic Early Paleozoic microfossils

Content Provider	PubMed Central
Author	Graham, Linda E. Wilcox, Lee W. Cook, Martha E. Gensel, Patricia G.
Copyright Year	2004
Abstract	Absence of a substantial pretracheophyte fossil record for bryophytes (otherwise predicted by molecular systematics) poses a major problem in our understanding of earliest land-plant structure. In contrast, there exist enigmatic Cambrian–Devonian microfossils (aggregations of tubes or sheets of cells or possibly a combination of both) controversially interpreted as an extinct group of early land plants known as nematophytes. We used an innovative approach to explore these issues: comparison of tube and cell-sheet microfossils with experimentally degraded modern liverworts as analogues of ancient early land plants. Lower epidermal surface tissues, including rhizoids, of Marchantia polymorpha and Conocephalum conicum were resistant to breakdown after rotting for extended periods or high-temperature acid treatment (acetolysis), suggesting fossilization potential. Cell-sheet and rhizoid remains occurred separately or together depending on the degree of body degradation. Rhizoid break-off at the lower epidermal surface left rimmed pores at the centers of cell rosettes; these were similar in structure, diameter, and distribution to pores characterizing nematophyte cell-sheet microfossils known as Cosmochlaina. The range of Marchantia rhizoid diameters overlapped that of Cosmochlaina pores. Approximately 14% of dry biomass of Marchantia vegetative thalli and 40% of gametangiophores was resistant to acetolysis. Pre- and posttreatment cell-wall autofluorescence suggested the presence of phenolic compounds that likely protect lower epidermal tissues from soil microbe attack and provide dimensional stability to gametangiophores. Our results suggest that at least some microfossils identified as nematophytes may be the remains of early marchantioid liverworts similar in some ways to modern Marchantia and Conocephalum.
Related Links	http://dx.doi.org/10.1073/pnas.0400484101
Starting Page	11025
File Format	PDF
ISSN	10916490
e-ISSN	10916490
Journal	Proceedings of the National Academy of Sciences of the United States of America
Issue Number	30
Volume Number	101
Language	English
Publisher	National Academy of Sciences
Publisher Date	2004-07-27
Access Restriction	Open
Rights Holder	National Academy of Sciences
Subject Keyword	Research in Higher Education
Content Type	Text
Resource Type	Article
Subject	Multidisciplinary

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

Early Trait Evolution in Liverworts (Marchantiophyta), with an emphasis on Oil Bodies and Paleozoic Taxa

Pellet microfossils: Possible evidence for metazoan life in Early Proterozoic time

Large spinose microfossils in Ediacaran rocks as resting stages of early animals

B cell receptors in TCL1 transgenic mice resemble those of aggressive, treatment-resistant human chronic lymphocytic leukemia

Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse

Podargiform Affinities of the Enigmatic Fluvioviridavis platyrhamphus and the Early Diversification of Strisores (“Caprimulgiformes” + Apodiformes)

Trace Element Concentrations Associated with Mid-Paleozoic Microfossils as Biosignatures to Aid in the Search for Life

Abiotic, Graphitic Microstructures in Micaceous Metaquartzite about 3760 Million Years Old from Southwestern Greenland: Implications for Early Precambrian Microfossils

Additional material of the enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida

Resistant tissues of modern marchantioid liverworts resemble enigmatic Early Paleozoic microfossils

Similar Documents

Early Trait Evolution in Liverworts (Marchantiophyta), with an emphasis on Oil Bodies and Paleozoic Taxa

Pellet microfossils: Possible evidence for metazoan life in Early Proterozoic time

Large spinose microfossils in Ediacaran rocks as resting stages of early animals

B cell receptors in TCL1 transgenic mice resemble those of aggressive, treatment-resistant human chronic lymphocytic leukemia

Polar front shift and atmospheric CO2 during the glacial maximum of the Early Paleozoic Icehouse

Podargiform Affinities of the Enigmatic Fluvioviridavis platyrhamphus and the Early Diversification of Strisores (“Caprimulgiformes” + Apodiformes)

Trace Element Concentrations Associated with Mid-Paleozoic Microfossils as Biosignatures to Aid in the Search for Life

Abiotic, Graphitic Microstructures in Micaceous Metaquartzite about 3760 Million Years Old from Southwestern Greenland: Implications for Early Precambrian Microfossils

Additional material of the enigmatic Early Miocene mammal Kelba and its relationship to the order Ptolemaiida

Resistant tissues of modern marchantioid liverworts resemble enigmatic Early Paleozoic microfossils