After last year’s first wave of covid-19 in the UK, individuals who had been discharged after hospitalisation suffered higher rates of coronary and respiratory disorders, and even diabetes subsequently over 140 days. As Dr Ami Banerjee of University College London explains, out of 48,000 cases, patients who had had acute covid-19 were four times more likely to be readmitted and 8 times more likely to die. Ami’s team suggests in their paper published in the British Medical Journal that diagnosis, treatment and prevention of post-covid syndrome needs an integrated approach.

In France, researcher Xavier Montagutelli describes how his team has observed that unlike the original virus, some of the newer Variants of Concern can infect mice in laboratories. They do not show serious illness, but nevertheless host the virus in their lungs. Whilst infection is unlikely in natural environments and not yet observed in the wild, it does show how the viral variants can extend the host range, perhaps leading to more opportunities for mutation. But this finding, posted as a pre-print, also perhaps represents an avenue for deeper gene-specific research that has not so far been possible.

Over in Colombia, Monica Carvalho of the Smithsonian Tropical Research Institute describes her team’s findings regarding the origins of the diversity and habitat of rainforests in south America. Looking at leaf fossils and pollen grains from 60 million years ago, they have found significant differences between the forests of the dinosaurs, and the ones we see today. As they write in the journal Science, it all changed when the Chixulub meteor hit the Gulf of Mexico and the global lights went out. The rainforests that grew back were simply not the same.

But much further back in time, some billion years ago, the forests of the world that were changing the chemistry and making seas inhabitable allowing complex multicellular life, consisted of pencil-lead sized algae quietly photosynthesizing in the shallows of an ocean in what is today remote Canada. Katie Maloney of University of Toronto Mississauga spotted fossils of just these when out on a field trip in Yukon territory. Publishing in Geology Magazine this week, her eagle-eyed finds shed light on this crucial epoch in life history of which there are scant fossilized remains.

Image: Rainforest canopy

Presenter: Roland Pease