Science Highlights

A chemical process used in the browning of food to give it its distinct smell and taste is probably happening deep in the oceans, where it helped create the conditions necessary for life. Known as the Maillard reaction after the French scientist who discovered it, the process converts small molecules of organic carbon into bigger molecules known as polymers. In the kitchen, it is used to create flavours and aromas out of sugars.

Moore, O.W. et al. Long-term organic carbon preservation enhanced by iron and manganese. Nature (2023). https://doi.org/10.1038/s41586-023-06325-9

Iron is an essential micronutrient for phytoplankton and plays an integral role in the marine carbon cycle. The supply and bioavailability of iron are therefore important modulators of climate over glacial-interglacial cycles. Inputs of iron from the Antarctic continental shelf alleviate iron limitation in the Southern Ocean, driving hotspots of productivity. Glacial meltwater fluxes can deliver high volumes of particulate iron. Here, we show that glacier meltwater provides particles rich in iron(II) to the Antarctic shelf surface ocean. Particulate iron(II) is understood to be more bioavailable to phytoplankton, but less stable in oxic seawater, than iron(III). Using x-ray microscopy at the I08 facility of the Diamond Light Source, we demonstrate co-occurrence of iron and organic carbon-rich phases, suggesting that organic carbon retards the oxidation of potentially-bioavailable iron(II) in oxic seawater. Accelerating meltwater fluxes may provide an increasingly important source of bioavailable iron(II)-rich particles to the Antarctic surface ocean, with implications for the Southern Ocean carbon pump and ecosystem productivity.

Jones, R.L., Hawkings, J.R., Meredith, M.P. et al. Antarctic glaciers export carbon-stabilised iron(II)-rich particles to the surface Southern Ocean. Nat Commun 16, 5015 (2025). https://doi.org/10.1038/s41467-025-59981-y

A UK-led international team of researchers has discovered elemental metallic copper and iron in the human brain for the first time. The team, comprised of scientists from Keele University and the University of Warwick in collaboration with the University of Texas at San Antonio (UTSA), used Diamond, and the Advanced Light Source located in California (USA) to identify elemental metallic copper and magnetic elemental iron within the amyloid plaques, chemical forms of copper and iron previously undocumented in human biology.

J. Everett et al. Biogenic metallic elements in the human brain. Sci. Adv. 7, eabf6707 (2021). DOI: 10.1126/sciadv.abf6707

The meteorite, called Allan Hills (ALH) 84001, was discovered in Antarctica in 1984 and is considered one of the oldest known rocks to reach Earth from Mars. The team’s analysis showed that organic molecules found in the Allan Hills meteorite were synthesised during interactions between water and rocks that occurred on the Red Planet about 3.6 – 4 billion years ago. Their findings were recently published in the journal Science. 

A. Steele et al. Organic synthesis associated with serpentinization and carbonation on early Mars. Science 375, Issue 6577 (Jan 2022). DOI: 10.1126/science.abg7905 

Using an array of microscopic (SEM, TEM, and confocal laser scanning fluorescence microscopy) and spectroscopic techniques (Raman, FTIR, and XANES), we demonstrated the presence of vestigial chitin in these fossil filaments and document the eukaryotic nature of their precursor. Based on those combined evidences, these fossil filaments and mycelium-like structures are identified as remnants of fungal networks and represent the oldest, molecularly identified remains of Fungi.

S. Bonneville et al., Molecular identification of fungi microfossils in a Neoproterozoic shale rock, Science Advances 6; doi: 10.1126/sciadv.aax7599