A new study in Current Biology suggests that restoration of a rainforest tree on tropical atolls depends upon the right soil fungi being present. The tree species, Pisonia grandis, is the backbone of life on and around atolls: everything from seabirds to the surrounding coral reefs depend on these trees. Research from Palmyra Atoll, the most remote island on Earth, suggests that these extraordinary island ecosystems are dependent upon a specific mycorrhizal fungi that supplies resources to these Pisonia trees.

MIT researchers developed a method for making an iron-containing gel that can form soft, magnetically activated structures. The gel could be the basis for microscopic robots and materials that can be controlled by an external magnet, for example to release drugs or grab biopsies within the body.

Between 50,000 and 10,000 years ago, many of the world’s largest mammals disappeared. Picture creatures like saber-toothed cats with 7-inch fangs and elephant-sized sloths. A new study reveals how their disappearance fundamentally reshaped food webs for the species that remain today, and why the changes were more pronounced in some parts of the world than others, particularly in the Americas.