7 Seeds

7 Seeds (7SEEDS セブンシーズ) is an ongoing science fiction manga series by Yumi Tamura. It has been published by Shogakukan since 2001, first in Betsucomi then in Flowers, and collected in 16 bound volumes. The series is set in a post-apocalyptic future long enough after a meteorite hits Earth that new species have evolved, and follows the struggles to survive of five groups of young adults after they are revived from cryonic preservation. The title comes from seven caches of supplies, called "seeds," laid down by the Japanese government. In 2007, the series won the Shogakukan Manga Award for shōjo manga.

Story
In the present day, before the start of 7 Seeds, when astronomers predict that Earth will be hit by a meteorite, the world leaders met to develop a plan for human survival, called the Seven Seeds project. Each country would cryonically preserve a number of healthy young people, which would allow them to survive devastation of the impact. After a computer determines that Earth is once again safe for human life, it would revive each group.

The Japanese government created five groups of survivors named Winter, Spring, Summer A, Summer B, and Fall. Each group consisted of seven members, who were not told what would happen before being put in cryonic preservation, and one adult guide who is trained in wilderness survival. These groups were scattered across Japan: the Summer groups in southern and northern Kyūshū, Fall in western Honshū, Spring in central Honshū near Tokyo, and Winter in Hokkaidō. The project also prepared sealed caches containing seeds and instructional books near the "seven Fuji". These seven Fuji are not related to the famous Mount Fuji, but are regional landmarks also named Fuji:
 * Bungo Fuji in Ōita Prefecture is Mt. Yufudake, where the cache is marked by a statue of the Buddha Dainichi.
 * Ogino Fuji in Kanagawa Prefecture is Mt. Kyogatake, where the cache is marked by a statue of Monjubosatsu (the bodhisattva Manjusri).
 * Kobe Fuji in Hyogo Prefecture is Mount Futatabi of the Rokkō Mountains.
 * Natori Fuji in Miyagi Prefecture is Mt. Taihaku, near Sendai, where the cache is marked by a statue of Kokūzō (the bodhisattva Akasagarbha).
 * Akan Fuji in Hokkaidō is Mt. Meakandake, where the cache is marked by a statue of Senju-Kannon (the goddess of mercy).

7 Seeds follows these five groups, as they are revived an undetermined time after the impact and come to terms with survival in a Japan that has greatly changed.

Characters
Every member of a group has a name containing a kigo (poetic seasonal word) related to the group name—for example, all of the members of the Spring group have names traditionally associated with spring. Each group consists of seven members plus a guide trained in wilderness survival. The five groups are listed in order of appearance in the series, which is different from the order in series chronology they were revived from cryonic preservation.

Summer group B
Summer group B was created after the other four Japanese groups as a backup, and consists of people who are healthy but rebellious or otherwise not well-adjusted to society. They emerge from cryonic preservation at the start of the series near an island in the East China Sea off the coast of Nagasaki Prefecture in western Kyūshū, and travel to the seed cache at the foot of Bungo Fuji in Ōita Prefecture.


 * Natsu Iwashimizu (岩清水 ナツ): A painfully shy, awkward and withdrawn 16-year-old girl, and the protagonist of the chapters about Summer group B. Natsu has difficulty expressing herself, and was always put down at home and bullied in school. However, she becomes essential to the group's survival by observing and writing down what they discover, such as which foods are edible. Natsu means "summer" and iwashimizu means "water trickling from rocks".
 * Arashi Aota (青田 嵐): The boyfriend of Hana from the Spring group, aged 17. He acts as the protector of Natsu, and in general he is depicted as a compassionate and considerate person. He was on the school swim team with Hana, and is afraid of insects. Arashi means "tempest" and aota means "green paddy".
 * Semimaru Asai (麻井 蝉丸): A young man with a rebellious personality, aged 18. Semi means "cicada", and asa means "ramie".
 * Matsuri Tendou (天道 まつり): The daughter of a farmer, aged 16. She had been running away from home prior to being cryonically frozen. Matsuri means "festival" and tendō means "heavenly path", a poeticism for the sun.
 * Chimaki Yamori (守宮 ちまき): An art college student, aged 19. Chimaki loves painting and sculpting, and he has a habit of carving and drawing murals on rock walls. Chimaki means "zongzi", and yamori means "gecko".
 * Hotaru Kusakuri (草刈 螢): A 12-year-old girl with a strong intuition, who always accurately predicts the weather. Hotaru means "firefly".
 * Kaname Mozunoto (百舌戸 要): A mysterious person of uncertain age, usually called just Mozu. He is very skilled at survival, and stands out for having a name element, mozu (百舌), that is an autumn kigo instead of summer. In volume 6, when he meets Hana of Spring group while she is in despair, he offers to kill her. In volume 12, he tells Botan he was nephew of the Prime Minister and a leader of the Seven Seeds project, and a flashback reveals that he was responsible for the creation of the Seven Seeds program, along with the selection of the members of Summer group A.
 * Botan Saotome (早乙女 牡丹): The guide for Summer group B. She used to be a policewoman, and therefore skilled in self-defense. Very outspoken and straight-forward in her communication. Botan means "peony".

Spring group
The Spring group emerges from cryonic preservation a few months after Summer group B near an island off the coast of the Kantō region of central Honshu, and travel to Ogino Fuji in Kanagawa Prefecture, where they find a note from Natsu of Summer group B. Later, Hana invites Takahiro, the surviving member of Winter group, to join the Spring group.


 * Hana Suguruno (末黒野 花): The 17-year-old girlfriend of Arashi Aota, and the main character of the chapters about Spring group. She is depicted as beautiful, attractive and strong-willed; she is described as a tomboy by Arashi and energetic by Fujiko and Haru. Hana learned an adequate amount of wilderness survival skills from her father during her childhood when he used to frequently take her to camping trips. She was on her school swim team and dabbled in rock climbing as a hobby. When she realizes that she may never meet Arashi again, she contemplates suicide, but when she learns that Arashi has survived in Summer group B she becomes determined reunite with the love of her life. Hana means "flower" and suguruno means "burning fields to make way for new crops".
 * Mansaku Tsunomata (角又 万作): A young man with a strong body, aged 18. Mansaku is a skilled archer. He is depicted as laid-back person who enjoys meditation and Tang Dynasty poetry. Mansaku means "witch hazel" and tsunomata means "red algae".
 * Fujiko Amacha (甘茶 藤子): A 17-year-old girl who aspires to become a doctor and an astronaut. She served as an overseas medical volunteer before she was put in cryonic preservation. Fujiko gets along well with Hana. Fuji means "wisteria" and amaciya is a variety of hydrangea.
 * Haru Yukima (雪間 ハル): A 16-year-old child-prodigy pianist, who can play other instruments such as ocarina. He is depicted as intelligent but bratty, snobby and reserved. When he realizes the world he knew is gone, he tells Hana he is relieved to be rid of the pressures of winning competitions and performing flawlessly to please the public. He is attracted to Koruri and begins teaching her the joys of appreciating music. Haru means "spring" and yukima means "break in snowfall".
 * Momotaro Nobi (野火 桃太郎): A 12-year-old genius from Sendai. Momo means "peach", taro means "oldest/first son", and nobi means "wildfire".
 * Chisa Taiami (鯛網 ちさ): An 18-year old woman from a prestigious family with strong political influence. She is a skilled potter. She is depicted as polite and obedient, using respectful language (see Honorific speech in Japanese), and is always drawn with her eyes mostly closed. Chisa means "lettuce", tai means "sea bream", and ami means "net".
 * Hibari Niigusa (新草 ひばり): A 12-year-old girl who remains in a coma after being revived. She is cared for by Chisa. Hibari means "skylark".
 * Tosei Yanagi (柳 踏青): The guide for the Spring group, age unknown. Before being put in cryonic preservation, Yanagi was a member of the Japan Self-Defense Forces. He is depicted as an arrogant disciplinarian and a misogynist. He dies saving the others by setting himself on fire after the giant praying mantis eggs that were laid inside his body hatched. To means "to step on", sei means "green", and yanagi means "willow". Written with different kanji, tousei can also mean "strength of a party".

Winter group
The Winter group emerges from cryonic preservation in the Pacific Ocean off the southern coast of Hokkaidō about fifteen years before the start of the series. Three members die during the thawing process; on the way to the cache at Mt. Meakandake, they are attacked by a sabertoothed tiger, killing their guide and Mutsuki. The remaining three, Mitsuru, Fubuki, and Takahiro, form a close relationship as they fight for survival.


 * Takahiro Aramaki (新巻 鷹弘): The main character of the chapters about Winter group. Takahiro was a talented and famous high-school baseball player, described as the best pitcher to appear in 50 years, and had played in Kōshien. He is attracted to Mitsuru, but when he realizes she is in love with Fubuki, helps the two get together. After Fubuki and Mitsuru's deaths, Takahiro survives on his own with two wolves named after them, which he raised from puppies, until he meets Arashi, Natsu, and Semimaru of Summer group B in the ruins of Tokyo. Later, he meets Hana of Spring group, who invites him to join them. Taka means "hawk".
 * Fubuki Samejima (鮫島 吹雪): Also a talented and well-known high-school baseball player who, like Takahiro, played at Kōshien, and was described as the shortstop of the century. He gets together with Mitsuru shortly before being killed by a tiger while saving Mitsuru and Takahiro. Fubuki means "snowstorm".
 * Mitsuru Kagurazaka (神楽坂 美鶴): A high-school student who studied traditional Japanese dance. She initially pretends to disdain Fubuki, but later admits to being a fan of both Fubuki and Takahiro from before being put in cryonically preservation. Unable to bear Fukubi's death, she dances in the snow and freezes to death. Tsuru means "crane".
 * Mutsuki Karezono (枯園 睦月): A first-year university student majoring in journalism. He jumps off a cliff after being mortally wounded by the tiger that kills Kumakawa. Mutsuki is the first month of the former Japanese lunisolar calendar.
 * Sayuru Kumakawa (熊川 冴): The guide for the Winter group. He is killed by a sabertoothed tiger soon after being revived. Sayuru means "freezing".

Fall group
The Fall group emerges from cryonic preservation about three years before the start of the series in the Sea of Japan off the coast of the Kansai region of western Honshu, and travel to Kobe Fuji in Hyogo Prefecture. They are led by Akio and Ran, who overthrew the group guide Ryoya and keeps the rest of the members enslaved with tasks such as raising corn, tending their livestock and weaving fabric. After they meet Arashi, Natsu, and Semimaru from Summer group B, the Fall group sets out to visit each Fuji.


 * Akio Haza (稲架 秋ヲ): The leader of Fall group. In the present day, he was a young but successful Internet businessman, who had studied abroad in America and became fluent in English and Spanish. He and Ran dominate the rest of Fall group, forcing them to work to quotas. Aki means "fall", and haza is a covering of rice straw used during harvest.
 * Ran Shishigaki (猪垣 蘭): An aggressive and selfish woman who used to work as a architect. She acts as Akio's enforcer and often practices English and Spanish with Akio so they don't forget their foreign language skills. She harbors a deep grudge against the organization that chose her to be a part of the Seven Seeds Project. Ran means "orchid" and shishigaki means "boar fence", which keeps vermin out of fields.
 * Hazuki Karita (刈田 葉月): A former Olympic competitor in judo. Hazuki is the eighth month of the former Japanese lunisolar calendar, corresponding roughly to September.
 * Kurumi Shikano (鹿野 くるみ): A kind, gentle woman who has experience staying in a farm in New Zealand. She falls in love with Ryuusei in the same team and eventually becomes pregnant with his child. Kurumi means "walnut".
 * Ryuusei Ogiwara (荻原 流星): A young man who acts like a playboy. Ryuusei means "meteor".
 * Akane Nashimoto (梨本 茜): A woman who is a skilled diver, depicted as having a strong intuition about ghosts and spirits. She and Kurumi develop a close friendship. Akane means "madder".
 * Sakuya Yamaki (八巻 朔也): A former law student with eidetic memory. Yamaki literally means "eighth volume" and is another name for the Lotus Sutra.
 * Ryoya Izayoi (十六夜 良夜): A former fireman and the irresolute guide for the Fall group. When he meets Natsu, Arashi, and Semimaru of Summer group B, he attempts to poison them all but is prevented by Semimaru and Arashi. Ryoya is another name for the Mid-Autumn Festival and izayoi means "waning moon".

Summer group A
The members of Summer group A were specially chosen for the Seven Seeds Project by the Japanese government. This project genetically engineered and conceived more than 100 babies, then raised them on an island and taught wilderness survival until they reached the age of 17, at which time seven of them were chosen and put in cryonic preservation. "Failures" from this project were said to have left the island to join the rest of society, but later it is revealed that they were actually killed and disposed. Each child was instructed in seven classes of technologies: water, fire, wind, earth, vegetation, animal, and medical, and at age 13, they chose to specialize in two classes; In the end, one survivor was selected to represent each class. None of the members of Summer group A have a family name. They emerge from cryonic preservation in the Pacific Ocean off the coast of southern Kyūshū.


 * Ango (安吾): A specialist in fire and water classes, and the main character of the chapters about Summer group A. He was the top student of the project, and a rival of Ryou's. He and Ryou reluctantly respect each other. Ango is attracted to Ayu and is friends with Koruri, Mayu, Nobara, and Shigeru. Ango means "calm and firm existence".
 * Koruri (小瑠璃): A specialist in wind and medical classes. She has naturally curly hair, and is a good hang-glider. Koruri is a kind of robin.
 * Ryou (涼): A specialist in fire and water classes. Ryou is a top student and Ango's rival. He is depicted as rebellious with a cold demeanor, capable of evaluating situations dispassionately, but he shows glimpses of compassion at times. Though he may not seem like it on the surface, Ryou cares a lot about Ango. Ryou means "cool".
 * Ayu (あゆ): Also known as Madonna for her beauty, Ayu is the best specialist in the plant class and also specalized in earth classes. She is sometimes bullied by other girls because they are jealous of her appearance and the attention she attracts from boys. She looks down on other human beings, frequently referring to them as idiots and filthy creatures. Ayu means "sweetfish".
 * Gengorou (源五郎): A specialist in animal and plant classes. Gengorou is depicted as a kind and mature person, and him and Ango respect each other as peers. Gengorou is a kind of beetle.
 * Ban (鷭): A specialist in animal and medical class. Ban is depicted as seeming slow and socially awkward, but he is quick on his feet when treating an injured person. Ban means "moorhen".
 * Nijiko (虹子): A specialist in earth and water classes, Nijiko is depicted as always calm and collected. She's with Ryou, but appears to not truly care for him. Niji means "rainbow".
 * Unami (卯浪): The guide of Summer group A. He is an overpowering jerk and has no qualms about hitting his students. After their revival, he becomes the target of revenge by Summer group A and is killed by all members.

Setting
7 Seeds takes place an unknown number of years after the collision of a large meteorite with Earth. As a result of the impact, the climate of Japan has greatly changed: in the Kansai region there are only two seasons, a dry season and a longer, heavier rainy season than the characters knew from the present day, and Takahiro of Winter group describes the winters in the northern island of Hokkaidō as being as mild as in Kanagawa Prefecture where he grew up. In addition, sea levels have risen greatly: downtown Yokohama is completely underwater, only the top hand of the statue in Nagasaki Peace Park is above the surface of the ocean. The geography of Japan has changed as well: after an eruption of Mount Aso, Kyūshū has been split into two islands, and the Kansai region is separated from central Honshū by a wide strait. The series depicts a Japan in which, as a result of the new environment and mass extinctions, ecosystems have changed and several new species of animals and plants have evolved.

For example, on the island where Summer group B first lands, off the coast of Nagasaki Prefecture, Botan notes how few of the ecological niches are filled, including no birds or flying insects, and that the limited number of species are still radiating to fill empty niches. In particular, a local rodent resembling a rabbit is the process of speciation into herbivorous and ravenously carnivorous versions, which are still visually similar. Other dangers new to the characters include swarms of carnivorous white cockroaches and gigantic venus flytraps, sundews, and nepenthes. Species that are unchanged but were previously unknown in Japan include banana trees and crocodiles. Semimaru notes that neither on the island nor on the Kyūshū mainland do they see any ants, bees, or similar insects.

In the Kansai region, Fall group domesticates sheep that have grown to resemble llamas, which can be ridden, milked, and shorn for wool, and flightless birds about the size of a chicken. Izayoi tells Natsu that a local wasp is deadly, killing with a single sting, and another species has a sting that sickens the victim for a day. According to Akio, corn is the only crop from their seed cache that grows in the area's soils, but Fall group also cultivates a variety of tobacco with a narcotic effect when smoked.

In the southern part of central Honshū, Natsu, Arashi, and Semimaru of Summer group B cross a desert with cactus scrub. Throughout the region they find remains of large reptiles, which remind Natsu of velociraptors from Jurassic Park, that revive from estivation during the rainy season. These "dinosaurs", as the characters call them, have grassland and woodland varieties, and during the rainy season are the dominant predator from the south coast to at least as far north as Tokyo.

On the island where the Spring group first lands, off the coast of the Kantō region, Hana notes that there are no vertebrates on land or in the sea, and Momotaro describes the ecology as similar to that of the Carboniferous Era. On land, there are giant insects the characters call "boat beetles" and swarms of bees with stings that are painful but not deadly, which force the group to live on rafts off-shore. In the island's swamps are giant praying mantis and giant dragonflies. While at the island, the group lives off shellfish and shallow-water nautiluses (which are mesopelagic in the present day), but see no bony fish. The characters find the climate changed as well, as it is too overcast to see the stars for the first two weeks after they are awake, even though it is spring, a season that in the present day is noted for clear weather.

On the mainland of the Kantō region, Spring group meets large aquatic lizards living among the submerged ruins of Yokohama, which hunt in groups. Nearby, in the ruins of central Tokyo, the party from Summer group B is attacked a giant preditory fish, which Takahiro of Winter group identifies as descended from a deep-sea fish, the only kind of bony fishes to have survived. They also meet a fungus-like growth Takahiro calls "blue mucus," which infects Hana's skin when she touches it. This growth goes dormant in the dry season, and Takahiro realizes it is intolerant of salt and uses it to cure her.

In northern Honshū near Sendai, Natsu, Arashi, and Semimaru of Summer group B find the first flowers they have seen during their journey over most of the length of Japan.

In southern Hokkaidō, Winter group encounters grasslands populated by many mammals they do not know, including small-eared rodents, herds of unknown ruminants, and tigers with saber-teeth. They also meet wolves with the ability to project illusions—normally used to help hunt, but one whose injuries are tended by Takahiro pretends to be Fubuki to help him reach the seed cache at Mt. Meakandake alone.

Development
In an author's note, Tamura says that  7 Seeds was inspired by news reports that near-Earth object (89959) 2002 NT7 might potentially collide with Earth.

Manga
7 Seeds is written and illustrated by Yumi Tamura and published by Shogakukan. It began serialization in the November 2001 issue of the monthly shōjo (aimed at teenaged women) manga magazine Betsucomi; in March 2002, it moved to the monthly josei (aimed at younger adult women) manga magazine Flowers. Serial numbers have been collected in 16 bound volumes, printed under the Flower Comics imprint. When collected, these serial numbers are grouped in unnumbered parts called "chapters", each focusing on a different group of survivors, with part titles containing a kigo (seasonal word) appropriate for the group name.

Radio drama
7 Seeds was adapted as a radio drama that was broadcast from 2003-12-09 to 2004-02-06. The nine episodes were collected on three drama CDs:


 * 7 Seeds 1, released on 2004-03-26, focuses on Summer group B and dramatizes the events of volume 1 of the manga.
 * 7 Seeds 2, released on 2004-04-23, focuses on Winter group and dramatizes events of volume 4 of the manga.
 * 7 Seeds 3, released on 2004-05-21, focuses on Spring group and dramatizes events of volumes 2 and 3 of the manga.

Reception
7 Seeds won the 2007 Shogakukan Manga Award for shōjo manga. The series is among the best-selling manga in Japan, having sold more than 10 million copies as of September 2008; volume 12 reached number 7 on the Tohan best-seller list and volume 13 reached number 10.