Katsushika Hokusai published not only ukiyo-e pictures, but also Hokusai Manga (Hokusai's Sketches) in which he presented how to draw assorted geometric patterns in addition to various examples of landscapes and figures of humans, animals, plants and so on. We drew Seigaiha (blue ocean wave) with auxiliary lines on the background of this drawing, and found it astonishingly close to the patterns of fish scales. Hokusai might have known it. For drawing this image, we referred to the research paper by Aman et al. (2018) eLife, 7:e37001, DOI: 10.7554/eLife.37001 that reported development of scales.
Fireworks likened to newly generated neurons have been launched from the brain. In recent years, it has been shown that neurons are continually generated in the brain of adult mammalians. At the very moment when these pyrotechnic 'stars' are engraved on your brain as an unforgettable memory of the summer, your new neurons should be working. We thank Dr. Itaru Imayoshi (Kyoto University) for providing the data.