7 Seeds is a Japanese manga series written and illustrated by Yumi Tamura. Set in a post-apocalyptic future, long enough after the meteorite struck Earth for new species to emerge, it follows the struggle of five groups of young people for survival after being revived from cryopreservation. The name comes from five groups of people in cryogenic chambers, as well as materials called “seeds” planted by the Japanese government.
Episodes – 01 – 24
Status – Completed
28 June 2019 – 26 March 2020
When astronomers predict a meteorite will fall on Earth, world leaders meet to develop a plan for human survival called the Seven Seeds Project. Each country agrees to preserve healthy young people with cryogenics that will enable them to survive the devastating effects of exposure. After the computer determines that the Earth is safe for human life again, it will revive each group.
The Japanese government is creating five groups of survivors named Winter, Spring, Summer A, Summer B, and Autumn. Each group consists of seven members, who are not told about what will happen before they are placed in cryopreservation, and one adult guide trained in wildlife survival. These groups are scattered throughout Japan: summer groups in southern and northern Kyushu, autumn in western Honshu, spring in central Honshu near Tokyo, and winter in Hokkaido.
Waking up many years later from cryogenic sleep, young men and women find themselves in a hostile environment devoid of any human life. Their former homeland, Japan, has changed a lot. Completely alone, they must rely only on themselves to survive in the new world.
The events of 7 Seeds take place an unknown number of years after the collision of a large meteorite with the Earth. As a result of the collision, the climate of Japan changed dramatically from what the characters knew to this day. The Kansai region has only two seasons: a dry season and a longer and heavier rainy season. Winter’s Takahiro describes winters on the northern island of Hokkaido as mild as those in Kanagawa Prefecture, where he grew up. In addition, the sea level has risen strongly: the center of Yokohama is completely under water, only the top of the statue in the Nagasaki Peace Park is above the ocean surface. The geography of Japan also changed: after the eruption of Mount Aso, Kyushu was divided into two islands, and the Kansai region was separated from the center of Honshu by a wide strait. The series depicts Japan, where ecosystems have changed and several new species of animals and plants have emerged as a result of a new environment and mass extinction.
For example, on the island where Summer Group B first landed, off the coast of Nagasaki Prefecture, Botan notes how few ecological niches have been filled, including the absence of birds and flying insects, and that a limited number of species still stand out to fill the empty niches. In particular, the local rabbit-like rodent is in the process of speciation into herbivorous and carnivorous species that are still superficially similar. Other hazards new to the characters include swarms of predatory white cockroaches and giant Venusian flycatchers, sundews, and nepenta. Fixed species previously unknown in Japan include banana trees and crocodiles. Semimaru notes that neither on the island nor on the mainland of Kyushu they see ants, bees or similar insects.
In the Kansai region, Fall’s group tamed flightless birds the size of a chicken and a sheep, which have grown to resemble llamas, which can be ridden, milked and sheared. Izayoi tells Natsu that the native wasp is deadly, killing with a single bite, while in other wasp species, the bite causes the victim to feel nauseous throughout the day. Corn is the only seed crop that grows in the area’s soils, Akio said, but the Fall group also grows a variety of tobaccos that have a narcotic effect when smoked.
In the south-central part of Honshu, Natsu, Arashi, and Semimaru from Summer Group B traverse the desert with cactus bushes. Across the region, they find the remains of large reptiles that come to life during the rainy season, reminiscent of Natsu’s velociraptors from Jurassic Park. These “dinosaurs,” as the characters call them, have a variety of pastures and forests, and during the rainy season they are the dominant predators from the southern coast to at least as far north as Tokyo.
On the island where Spring’s group first lands, off the coast of the Kanto region, Hana notes that there are no vertebrates on land or sea, and Momotaro describes the ecology as similar to that of the Carboniferous. The land is home to giant insects, which the characters refer to as “boatmen,” and swarms of bees with painful but not fatal stings that force the group to live on rafts off the coast. The island’s swamps are home to giant praying mantises and giant dragonflies. On the island, the group feeds on molluscs and shallow-water nautilus, but does not see bony fish. The characters discover that the climate has changed as well, as it was too cloudy to see the stars for the first two weeks after they woke up, even though it is spring, a season marked by clear weather these days.
On the mainland of the Kanto region, the Spring Party encounters large aquatic lizards that hunt in groups among the flooded ruins of Yokohama. Nearby, in the ruins of central Tokyo, Group B of the Summer Group is attacked by a giant predatory fish, which Takahiro of the Winter Group identifies as a descendant of a deep-sea fish, the only bony fish that has survived. They also encounter a fungal growth, which Takahiro calls “blue slime,” which infects Hana’s skin when she touches it. During the dry season, this growth falls asleep, and Takahiro realizes that he cannot tolerate salt and uses it for treatment.
In northern Honshu, near Sendai, Natsu, Arashi and Semimaru from Summer Group B find the first flowers they see on their travels across most of Japan.
In southern Hokkaido, the winter group encounters pastures inhabited by many unfamiliar mammals, including small eared rodents, herds of unknown ruminants, and saber-toothed tigers. They also encounter wolves with the ability to create illusions, which are commonly used when hunting.