Probably the most impressive jellyfish invasion began in 1982 when a few, small baseball-sized hermaphrodite jellyfish got into the Black Sea, probably in the ballast water of a visiting freighter, found conditions to their liking, and began to reproduce in a major way. In order to explore the structure of the Jellyfish galaxies in 3D and calculate the timescales of their transformation, Dr. Callum Bellhouse of the University of Birmingham in the U.K. created interactive models that can also be experienced in virtual reality.
This includes Scyphozoans, the true jellyfish; Staurozoans, or stalked jellyfish, which remain in the polyp stage and attach to the ocean floor rather than swim around; Cubozoans, or box jellyfish; and Hydrozoans, a complex class of animals that often produce small medusae resembling simple jellyfish.
Because jellyfish are naturally found in a wide range of salinities, temperatures, oxygen concentrations, and depths (including 3700 m or deeper in the Mariana Trench) ( 14 , 15 ), these biohybrid robots also have the potential to be deployed throughout the world's oceans.
Marker shapes indicate the type of aquatic robot, from robots composed of biological tissue, such as the medusoid and robotic ray made from rat cardiomyocytes seeded on silicon scaffolds ( 9 , 10 ), to purely mechanical robots, including bioinspired robots ( 3 , 7 , 33 , 34 ) and AUVs ( 35 ). Marker colors indicate the type of propulsion, including medusan (jellyfish swimming), thunniform (fish swimming), rajiform (ray swimming), and propeller-driven locomotion.
Increased blooms can have negative impacts on human economic activities, clogging cooling water intakes at coastal power plants, bursting fishing nets and contaminating catches, killing off fish farms, reducing commercial fish abundance through competition, and interfering with fisheries and tourism.
Jellyfish also depend on a loose network of nerves located within their epidermal and gastrodermal tissue (outer and inner body walls, respectively) to detect touch and a circular ring throughout the rhopalial lappet located at the rim of their body.
Other species, like upside-down jellies (Cassiopea species) and Australian Spotted gallumboverde (Phyllorhiza punctata), have symbiotic relationships with algae (zooxanthellae), and they obtain enough carbohydrates from them to not need additional food sources.
This should not be surprising when considering the identical nature between plants and animals as pointed out by Frantisek Baluska, Dieter Volkmann, Andrej Hlavacka, Stefano Mancuso and Peter W. Barlow in Neurobiological View of Plants and Their Body Plan (Communication in Plants, Springer-Verlag Berlin Heidelberg 2006) in that both rely on identical sexual processes utilizing fusion between sperm cells and oocytes (female egg cells), both develop immunity when attacked by pathogens, and both use the same methods and means to drive their circadian rhythms (patterns of biological activity synchronized to day-night cycles).