eLife – My WordPress Site

Morphological comparison of the Apex Chert and the Strelley Pool Formation microfossils with EM-P. Images (A-D) are TEM images of EM-P cells forming intracellular vesicles (ICVs) and intracellular daughter cells. The numbered arrows in these images point to different stages of ICV formation (see Figure 1—figure supplement 1 and 2). Images (E, F, K & L) show TEM, SEM, and STED microscope images of EM-P cells with ICVs and surface depressions (black arrows). Cells in image F were stained with universal membrane stain, FM5-95 (red), and DNA stain, PicoGreen (green). Images (G-J & M) are spherical microfossils reported from the Apex Chert and the Strelley Pool Formation, respectively (originally published by Schopf and Packer, 1987; Delarue et al., 2020 ; Schopf and Packer, 1987; Delarue et al., 2020). Cyan arrows in images (E-H) point to cytoplasm sandwiched between large hollow vesicles. The arrow in the image I points to the dual membrane enclosing the microfossil. Morphologically similar images of EM-P cells are shown in Figure 1—figure supplement 3. Black arrows in images (K-M) point to surface depressions in both EM-P and the Strelley Pool Formation microfossils, possibly formed by the rupture of ICVs as shown in (D & E) (arrows) (also see Figure 1—figure supplements 4–6). Scale bars: (A-D) (0.5 µm) (E, K, & L) (2 µm), and 5 µm (F). -- eLife

Biosignatures & Paleobiology, Fossils & Paleontology

On The Nature Of The Earliest Known Lifeforms

by Keith CowingFebruary 25, 2026February 25, 2026

Microfossils from the Paleoarchean Eon are the oldest known evidence of life. Despite their significance in understanding the history of life on Earth, any interpretation of the nature of these microfossils has been a point of contention among researchers.

The four helices conserved across the Lipocone superfamily constitute a cone-like structure, with the helices tending to coalesce on one end and open out into a pocket on the other, lined by the conserved sequence positions. Image credit: Burroughs, Nicastro and L. Aravind (CC BY 4.0)

Biochemistry & Organic Chemistry, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life

Origins Of Wnt Signalling Reveals A Protein Superfamily Across The Tree of Life

by Keith CowingSeptember 11, 2025September 18, 2025

A paleo-art reconstruction of a scene from the late Early Triassic, showing a coastal mudplain to alluvial ecosystem in the Heshanggou Formation, North China Credit Mr J Sun (CC BY 4.0)

Biogeochemical Cycles & Geobiology, Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives

Fossils Reveal Rapid Land Recovery After End-Permian Extinction

by Keith CowingFebruary 24, 2025February 24, 2025

Strand separation by salt cycling -- eLife

Astrochemistry, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Origin & Evolution of Life

Prebiotic Gas Flow Environment Enables Isothermal Nucleic Acid Replication

by Keith CowingOctober 9, 2024October 9, 2024

Archaeal proteomes were systematically scanned to identify EPs with potential antimicrobial activity. Circular bars denote the log10-transformed average active (red) and inactive (blue) EPs discovered by APEX. A peptide was classified as active if its predicted mean MIC against tested bacterial strains was ≤100 μmol l−1. The values were normalized by the number of proteins per organism scanned. Archaea with peptides that were synthesized are indicated by a light red square, and those experimentally validated as active are highlighted with a dark red square. -- Nature Microbiology

Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Genomics, Proteomics, Bioinformatics, Microbiology & Virology, Origin & Evolution of Life

Early Replicators

by Keith CowingMay 12, 2024May 12, 2024