About 10,400 wakasagi, a cold-water smelt never native to Haizuka Dam, died amid heat and drought in Hiroshima. Nobody knows who brought them, and Japan's invasive species law does not cover fish moved within Japan.
Genji fireflies flash about every 4 seconds in eastern Japan and every 2 in the west. A survey of 164 populations found western and Kyushu lineages in over 70% of Tokyo's, most likely brought in by people.
Fossils said the Late Cretaceous Arctic was warm enough for dinosaurs, but climate models could not reproduce it. A Japanese team let Earth's axial tilt roam its full range and points to geography as the amplifier.
An experiment at Japan's SPring-8 finds davemaoite holds 0.08 wt% water at most, a tenth of past estimates, and points Earth's deep water to subducted crust instead.
Japan culled 1,381,700 deer and wild boar in fiscal 2024, and 5.6 percent of that mass became meat. The rest goes to a hole in the ground or an incinerator, and the capacity is not there. Scotland does it differently.
Yamanashi and Riken researchers cut out the whole Y chromosome to make female clones of male mice. Read next to the same university's finding that cloning dies at 58 generations, and Osaka's eggs from male cells.
A 10 mm jellyfish rewound itself ten times in two years. A genome paper on about 1,000 genes cast it as nature's Yamanaka reprogramming; a US researcher attacked that premise with Japanese data it never cited.
Three fossils, two of them picked up by amateurs more than twenty years ago, sat in a Hokkaido museum drawer until a CT scan added ten million years to a family of ammonites long thought extinct.
Japan's NIES has made iPS cells from four endangered birds. The flightless Okinawa rail has lost one of the two genes birds use to spot a virus. Inside the minus-160°C cell bank and the brain organoids grown from it.
Rausu, Rishiri, hosome, ma-kombu: four kelps sold under four names and four price tiers. A Hokkaido University team read the DNA of 475 plants and found no genetic line between them.
Hokkaido University and Japan's forestry institute modelled all 349 ski areas in the country. At 4°C of warming, only seven stay open 100 days a year on natural snow. At 2°C, 53 do.