A lot happened in the hundreds of millions years separating the first and last eukaryotic common ancestors, but when and how most features arose remains a mystery.
Today’s extinction rates are sky-high. But scientists debate if that’s sufficient evidence to conclude that Earth is undergoing a mass extinction event—or whether that’s even a helpful designation.
Extinction is a natural part of life on Earth. But occasionally, extinction rates have surged far beyond usual levels, driving mass extinction events that have reshaped the trajectory of life.
The discovery of ancient clades of brittle stars at the bottom of the Pacific Ocean adds to concerns that commercial exploitation of the area could destroy numerous taxa before they’ve even been identified.
The International Institute for Species Exploration announces its picks of novel species discovered in the past year, including a carnivorous mammal, a tiny shrimp, and a fungus.