Long before humanity existed, “algae” have been thriving on Earth. Although often overlooked, algae are gaining attention as a potential solution to global challenges. Not only do they convert carbon dioxide and water into oxygen and sugar through photosynthesis, but they also provide high-nutrient food, alternative fuels to petroleum, and raw materials for cosmetics. New technological developments are underway to unlock their latent power.
At the Japan Pavilion of Expo 2025 Osaka, Kansai, an exhibit will showcase Japan's innovations in algae technology. Among these is the beloved character Hello Kitty, reimagined in the form of various algae. Over 300,000 species of algae are known to exist in nature, ranging from microscopic sizes to over 50 meters in length. Out of these, 32 species have been selected to become “Algae × Hello Kitty” and will be displayed as life-sized sculptures in the Japan Pavilion.
Explore Shapes that Catch Your Eye
In anticipation of the Expo in April 2025, this article introduces the “Algae × Hello Kitty Encyclopedia.” Algae possess diverse and unique characteristics, each with its own distinct shape. While learning about their capabilities and potential, why not find your favorite among these unexpected encounters with 32 types of algae?
*The “Algae × Hello Kitty” designs are inspired by real algae species. To effectively convey the appeal of algae, each character emphasizes the outer shape characteristics of the species. As a result, the designs may differ from actual algae in terms of size, color, and shape.
Haptophyte
Braarudosphaera bigelowii
Braarudosphaera
Size: 0.01～0.02mm (cell diameter)
Habitat: saltwater
This organism, with pentagonal calcium carbonate scales forming a dodecahedron, has remained unchanged since the Late Cretaceous, when dinosaurs roamed the Earth.
Covered in spiky scales, this organism has a yellowish-brown appearance and appears in winter ponds. It aids water purification but smells fishy if it overgrows.
Twisted like a chocolate cornet, this Helicoides species differs from its flat, fan-shaped relatives. It inhabits ponds, swimming with a drill-like spinning motion.
It has a capsule-like shell, connecting with other individuals through protrusions to form a linear filament, resembling skewered dumplings. It inhabits warm seas.
It has protrusions at both ends, releasing sticky mucus to connect with other individuals in a zigzag pattern or attach to rocks and large aquatic plants.
Two equal-sized triangular shells fit together like a bento box. This genus include square and star shapes species. It can absorb heavy metals, aiding environmental purification.
Ellipsoidal with two antenna-like flagella, easy to crossbreed and widely used in genetic research. It evolved into 4-celled Tetrabaena and multicellular Volvox.
Flat like a fan, it extends a long flagellum forward. A red eyespot helps it detect light direction. It swims in a spinning motion in rice paddies and ponds.
Tiny and round, it lives in soil or ponds, excelling at photosynthesis. Half protein, it’s valued as a nutrient-rich food. Many similar-looking species exist.
Shaped like a windmill, its disk-like shell has six fan sections with alternating ridges and grooves. It lives in shallow seas, sometimes linking with neighbors.
A diatom with a lemon-shaped, glassy shell. It attaches densely to sand in shallow seas and is considered a strong, durable material for industrial use.
A diatom with elongated, glassy shells arranged flat. They slide against each other, extending and contracting like rafts, moving dynamically. It inhabits the sea.
A diatom with barrel-shaped cells forms filaments, sometimes coiling. It thrives in murky ponds and lakes, absorbing nitrogen compounds and phosphate for water quality.
Spiral-shaped (“spirulina” means “spiral” in Latin), it twirls on pond bottoms. The health food known as “spirulina” is actually another cyanobacterium, Arthrospira.
Covered in spherical branches, this seaweed is called “sea grapes” but is officially Kubi-rezuta. It grows in Okinawa, Japan's southwest islands, and Southeast Asia.
Brown and amorphous like a cream puff, this seaweed is hollow and collapses when dry. Found along Japan’s shores, it's studied for biofuel and plastic production.
Crescent-shaped, it divides at the center to reproduce, with each half regrowing. Two can merge to form offspring. It lives at the bottom of rice paddies and marshes.
Originally filamentous and attached to rocks, it becomes spherical its filaments roll along lake beds. In Lake Akan, its primary habitat, wind causes it to roll, its primary habitat.
Brown and ribbon-like, it can grow up to 7m long. Among its 20 relatives, it’s prized as a delicacy. Edible but too thick to eat raw, it’s ideal for making flavorful broth.
Composed of dense, ovoid cells, it produces diesel-like hydrocarbons, making it a promising biofuel for addressing environmental issues. It floats in pond water.
Shaped like a four-leaf clover, it's found worldwide. Once debated whether it's four linked individuals or one with four cells; Japanese studies confirmed the latter.
Slender cylindrical stems branch irregularly. It attaches to seaweed, optimizing light for photosynthesis. The fibers are slimy, giving it a smooth texture when eaten.
Chief Researcher, Fungi and Algae Research Group, Department of Botany, National Museum of Nature and Science. Ph.D. in Science. Specializes in the taxonomy, algal flora, and history of phycology, with recent research on freshwater algae growing in rivers. Currently studying algae in the vicinity of the Imperial Palace. Oversees the "Phylogeny Square" exhibit in the permanent collection of the museum’s Global Gallery and has developed the educational museum product "Kahaku Cards" to accompany the exhibit.
Microalgae Supervision: Takashi Nakada
Lecturer, Hokkaido University. Graduated from the Faculty of Science and completed the Ph.D. program at the Graduate School of Science, University of Tokyo. Previously served as a Specially Appointed Lecturer at Keio University’s Graduate School of Media and Governance. Specializes in the taxonomy of micro-green algae and has a keen interest in scientific and Japanese names of organisms, proudly expanding his collection of reference books daily.
Let’s Share!
Have you found your favorite shaped “Algae × Hello Kitty”? Share your Monthly JP pavilion and circulate your thoughts.
