As Earth faces unprecedented climate change, a look into the planet’s deep past may provide vital insights into what may lie ahead. But knowledge of the natural world millions of years ago is fragmented. A 15-year study of a site in Bolivia by a joint U.S.-Bolivia team has provided a comprehensive view of an ancient ecosystem when Earth was much warmer than it is today, and changed how we look at the Andes.
A pair of studies published April 14 in the journal Science paint a new picture about apes, ancient Africa and the origins of humans. Many scientists had once hypothesized that the first apes to evolve in Africa more than 20 million years ago ate primarily fruit and lived within the thick, closed canopy of a nearly continent-wide forest ecosystem. Instead, the new research indicates that early apes ate a leafy diet in a more arid ecosystem of varyingly open woodlands with abundant grasses.
A new study published April 30 in the Proceedings of the National Academy of Sciences identified three factors critical in the rise of mammal communities since they first emerged during the Age of Dinosaurs: the rise of flowering plants; the evolution of tribosphenic molars in mammals; and the extinction of non-avian dinosaurs, which reduced competition between mammals and other vertebrates in terrestrial ecosystems.
An international team led by the University of Washington has discovered a way to determine the tree cover and density of trees, shrubs and bushes in locations over time based on clues in the cells of plant fossils preserved in rocks and soil.
New work in Argentina where scientists had previously thought Earth’s first grasslands emerged 38 million years ago, shows the area at the time covered with tropical forests rich with palms, bamboos and gingers. Grit and volcanic ash in those forests could have caused the evolution of teeth in horse-like animals that scientists mistakenly thought were adaptations in response to emerging grasslands.