Researchers propose that some of the planet’s earliest photosynthesizers benefited from a slowing of the Earth’s rotation that allowed them to produce a surplus of oxygen and paved the way for more complex life.
Researchers report chemical and molecular signatures of microbial activity from millions of years ago in mineral samples from abandoned mines in Sweden and nearby countries.
The finding that a bacterium within a bacterium within an animal cell cooperates with the host on a biosynthetic pathway suggests the endosymbiont is, practically speaking, an organelle.