Inge Johnsson/Alamy Stock Photo
Iguazu Falls, on the border of Argentina and Brazil, is the largest waterfall system in the world. It’s just one of the many bodies of freshwater that scientists measured using satellite imagery. Their finding? The world’s rivers and streams take up an impressive 45% more surface area than expected.
JOE MCDONALD/GETTY IMAGES
Venom drips from the fangs of a prairie rattlesnake, one of more than 200,000 animals that produces such toxins. But venom isn’t all bad: Researchers have used the substance to create six modern drugs, with more in development.
Nigerian Rose Kough and her 6-week-old baby receive antiretroviral drugs to avoid mother-to-child HIV transmission. Nigeria has the highest number of babies born with HIV. But even though it has made pregnant mothers a priority for more than a decade, progress has been slow.
LEO CORREA/AP Photo
Flames engulf the 200-year-old National Museum of Brazil in Rio de Janeiro. Many of the museum’s 20 million specimens—including the oldest known human fossil from Latin America—were lost or severely damaged in the September fire, exacerbated by a missing sprinkler system. The fossil, a skull known as Luzia, was later recovered.
SYLVAIN CORDIER/GAMMA-RAPHO/GETTY IMAGES
Monarch butterflies swarm in Michoacán state in Mexico during the winter. Rising numbers of parasitic infections and easy access to “pit stops” of nonnative milkweed plants have caused many butterflies to drop out of the annual flight from North America to Mexico, perhaps contributing to two decades of plummeting populations.
Skopei Films/©TU Delft
A four-winged robot in flight, its path traced with a time exposure. This agile robot, created by researchers in Delft, the Netherlands, maneuvers using passive aerodynamics to mimic the sliding motion a fruit fly makes when avoiding swatting hands.
JESSE S. JONES/UNIVERSITY OF FLORIDA
A pediatrician cares for a premature baby at the University of Florida Health Shands Children’s Hospital neonatal intensive care unit in Gainesville. Most of the 500,000 preemies born annually in the United States receive routine antibiotics, in many cases without evidence of infection. Now, some scientists worry that the drugs could damage their developing gut microbiomes and increase their chances of getting sick later in life.
In Kootenay National Park in Canada, a paleontologist uses a rock saw to remove Cambrian-era fossils dating back 500 million years. In this isolated part of the Burgess Shale, accessible only by helicopter, researchers have discovered a rich trove of these fossils, shedding new light on the early development of life.
Pran Gopal Mondal, 46, stands on Polder 32, a shrinking artificial island in Gunari, Bangladesh. The country has built 139 polders in an attempt to protect land from the increasing incursions of salty water brought on in part by climate change.
Children in Papua New Guinea are some of the main victims of yaws disease, a bacterial infection caused by Treponema pallidum that spreads through simple contact and attacks bones and skin—causing bright pink lesions and lifelong pain. Scientists hope to eradicate this little-known disease with a massive public health campaign—if governments, funding organizations, and the disease itself cooperate.
TIMOTHY ALLEN/GETTY IMAGES
A free-diving member of the Bajau people swims with a school of jack fish. New research has found the Indonesian natives—who spend long periods hunting underwater in low-oxygen conditions—carry a gene variant for larger spleens to compensate for the lack of oxygen.
Immunologist Helen Dooley of the University of Maryland School of Medicine in Baltimore draws blood from the fin of a nurse shark. Shark blood antibodies are nanoscopic, making them prime candidates for creating future drugs that could treat cancer and other diseases.
WANG CHI LAU/EMBRYOLOGY COURSE AT THE MARINE BIOLOGICAL LABORATORY
The transition from single cell to multicell organisms—a major step in evolution—may not have been as complex as originally thought. Students in the Marine Biological Laboratory in Woods Hole, Massachusetts, use multiple stains to highlight the specialized cells in these delicately constructed juvenile squid, Loligo pealei.
The successful first flight of the SpaceX Falcon Heavy rocket carried a whimsical payload—CEO Elon Musk’s personal Tesla Roadster, piloted by “Starman,” the space-suited dummy. Here, he is seen speeding away from Earth on an orbital pathway toward Mars. Since the February launch, SpaceX has shifted attention to creating an even larger rocket to advance commercial space travel.