Life developed when there was no oxygen on earth. It was an anoxic environment dominated by bacteria, who instead of oxidation and reduction, as our mitochondria do to produce energy, probably extracted various substances by means of fermentation.

But there has long been another possibility; a kind of “oxygen-free respiration” hinted at in studies on primordial microbes that are still found in anoxic habitats today. There have been found genes in microbes that perhaps encode for a primordial respiration enzyme.

Yet proving the existence of this respiratory enzyme and isolating it requires time and effort. The complex is fragile and often fell apart during attempts to isolate it from the membrane. 

Compared to cisgender people (gender identity corresponds to their sex), an analysis of over 600,000 adults finds transgender and gender-diverse adults are three to six times more likely to be diagnosed as autistic. 

The findings are simply exploratory and about co-occurrence between gender identity and autism diagnoses, they cannot inform or suggest causal links.  These correlations have confounders.

Egyptian coffins and mummy cases have been found covered in a mysterious 'black goo'. What is this goo made from and what can it reveal about Egyptian funerary practice? The British Museum's Kate Fulcher has detailed answers but you can read a summary below.

Djedkhonsiu-ef-ankh died almost 3,000 years ago in ancient Egypt. He was a priest in the temple of Amun at Karnak, where he was an ‘Opener of the Doors of Heaven’ - permitted to open the temple sanctuary which contained the image of their deity.

An annotated list of 219 pathogens that infect plants in Brazil, including many agriculturally important species, shows just how precarious things can be when it comes to maintaining an affordable, sustainable food supply.

We eat various foods and our metabolism converts it to energy our bodies can use. This is a hallmark of life, across plants, animals, algae and bacteria. Energy is a defining characteristic of living.

A lava tube is just what it sounds like; a cave created when the surface of lava hardens but continues to flow underneath. When that trickles to a halt, the cave is left behind.

These remaining caves exist on Earth and high-resolution pictures taken by interplanetary probes inferred lava tubes on Mars and Luna by observing linear cavities and sinuous collapse chains where the galleries cracked. A new paper measured the size and gathered the morphology of lunar and Martian collapse chains (collapsed lava tubes), using digital terrain models obtained through satellite stereoscopic images and laser altimetry taken by interplanetary probes.