- Footprints preserve terminal Pleistocene hunt? Human-sloth interactions in North America
Contemporaneous sloth and human footprints from the terminal Pleistocene at White Sands National Monument suggest stalking.
- Neuronal noise as an origin of sleep arousals and its role in sudden infant death syndrome
Temperature-induced arousability during sleep is a missing piece in the puzzle for triggers of sudden infant death syndrome.
- Observations of biogenic ion-induced cluster formation in the atmosphere
On the ability of biogenic vapors to initiate ion-induced cluster formation in the boreal forest.
- Guns, germs, and trees determine density and distribution of gorillas and chimpanzees in Western Equatorial Africa
We quantify the impacts of poaching, Ebola, and habitat degradation on western lowland gorillas and central chimpanzees.
- The delivery of water by impacts from planetary accretion to present
Impact melts and breccias trap surprisingly large quantities of water carried by carbonaceous chondrite–like impactors.
- Most atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding
Sea-level rise and wave-driven flooding will damage freshwater resources of most atolls and soon render them uninhabitable.
- Moving chairs in Starbucks: Observational studies find rice-wheat cultural differences in daily life in China
More people in wheat-growing northern China were sitting alone and moved a chair blocking the aisle in cafes than people in the rice-farming south.
- Insight into structural remodeling of the FlhA ring responsible for bacterial flagellar type III protein export
Cooperative remodeling of the FlhA ring terminates hook assembly and initiates filament assembly at the hook tip.
- Crystal structure and equation of state of Fe-Si alloys at super-Earth core conditions
This is the first direct determination of Fe-Si alloy structures at pressures found in the cores of super-Earth planets.
- Flexible active-matrix organic light-emitting diode display enabled by MoS2 thin-film transistor
Highly flexible organic light-emitting diode display was demonstrated using MoS2 TFTs as an active-matrix backplane.
- Experimental entanglement of 25 individually accessible atomic quantum interfaces
As an important step toward quantum networking, a record-high number of atomic quantum interfaces are entangled together.
- Multi-watt, multi-octave, mid-infrared femtosecond source
One-micrometer wavelength ultrafast laser emission is transformed to a powerful tool for ultrabroadband mid-infrared spectroscopy.
- Negative-pressure polymorphs made by heterostructural alloying
Mixing materials with different crystal structures leads to new phases that otherwise would require negative pressure to be made.
- The role of electron irradiation history in liquid cell transmission electron microscopy
New nanofluidic LC-TEM devices enable controlling and understanding electron irradiation history effects on liquid samples.
About The Cover

COVER Lingering questions about the evolutionary history of baleen whales are finding answers, thanks to a new genomics study. To date, baleen whales' evolutionary history has been difficult to decipher, in part because of conflicting evidence from genes and morphology. Ulfur Arnason et al. conducted whole genome sequencing of six baleen whale species, several of which had not been sequenced before. The researchers then produced a phylogenetic tree and analyzed "conflicts" in it; formation of new baleen species, they conclude, occurred not via classical Darwinian patterns but instead by a more gradual process. It involved new species evolving from a single ancestral species while still inhabiting the same geographic region. [CREDIT: MEGAN WHITTAKER/ALAMY STOCK PHOTO]