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Two beautiful but highly poisonous flowers are giving scientists a new way to think about medicine. Researchers at Michigan State University and the Czech Academy of Sciences studied wolfsbane and larkspur. These plants make complicated chemicals called diterpenoid alkaloids. Some members of this chemical family may be useful in future treatments for pain, cancer or malaria, but they are difficult to collect and reproduce. The team searched through thousands of plant genes and identified six enzymes that help build atisinium, one of these complex compounds. They then placed the genetic instructions inside tobacco plants. The tobacco acted like a small biological factory and produced the target chemical steps. This does not mean that the poisonous flowers themselves are safe or that a new drug is ready. Eating even a small amount of wolfsbane can be deadly. The important result is that researchers now understand part of the plant's chemical assembly line. That knowledge could make it easier to produce rare compounds sustainably and test them carefully in the laboratory.

On August 12, a total solar eclipse will sweep across parts of Greenland, Iceland, northern Russia, Spain and a small corner of Portugal. A much larger area, including most of Europe and parts of Canada and the northern United States, will see a partial eclipse. During a total eclipse, the Moon moves directly between Earth and the Sun. For a short time, it blocks the Sun's bright surface and reveals the corona, the hot outer atmosphere that normally disappears in the glare. The shape of the corona is never exactly the same because it is controlled by the Sun's changing magnetic activity. Viewers may see long white streamers and red prominences around the dark Moon. NASA will provide live coverage for people outside the eclipse path. Eye safety is essential. Ordinary sunglasses are not strong enough, and eclipse glasses should meet the ISO 12312-2 safety standard. Only observers inside the path of totality may remove approved glasses during the brief moment when the Sun is completely covered.

A sea creature no bigger than a grain of rice looks like a bright green cartoon sheep, but its cleverest feature is hidden inside its body. The leaf sheep, or Costasiella kuroshimae, lives in warm waters near Japan, Indonesia and the Philippines. It eats a type of green algae and keeps some of the algae's chloroplasts instead of digesting them. Chloroplasts are the tiny structures that plants use to capture sunlight. By storing them in the leaf-shaped parts on its back, the sea slug can gain extra energy through photosynthesis. This unusual process is called kleptoplasty, which means stealing useful cell parts from food. The animal's green color also helps it hide among algae, while the pointed structures on its back may provide chemical protection. Scientists formally described the species only in 1993. Advances in underwater and macro photography later made its sheep-like face famous online. Its two apparent ears are actually rhinophores, sensitive organs that help it smell and taste the water while searching for food.

Record heat and drought have lowered the Danube River, revealing something that is normally hidden underwater: the foundations of a huge Roman bridge. The remains lie near Gigen in northern Bulgaria. Emperor Constantine I ordered the bridge, and it opened in A.D. 328. It connected the Roman city of Ulpia Oescus with Sucidava, in present-day Romania. At more than two kilometers long, it was one of the most ambitious bridges of the ancient world. However, its working life was surprisingly short. Historians believe that much of it was destroyed around A.D. 367, only about forty years after it opened. Archaeologists from the Regional Historical Museum in Pleven used drones and aerial photography to map the exposed stones and study their condition. Low water creates a rare research opportunity because the river usually covers the remains. Yet the discovery also carries a warning. The same drought and heat that exposed the bridge are causing serious problems for shipping, agriculture and energy production along major European rivers.