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"Bring science home" all
Written by Seven Kings
Seaweed is a red algae of the genus Nori (porphyra), which is a common ingredient in many parts of China. In East Asian countries such as Japan and South Korea, seaweed is a must at home. In Japan, seaweed is called nori and is used to make foods such as sushi. In Korea, seaweed can be made with seaweed wrapped rice.
Because the people of East Asia love to eat, seaweed has become the most economically valuable seaweed in the world, with an annual global output value of about 1.8 billion US dollars, and the annual production of seaweed in Asia is 6.5 million tons. Red algae is high in protein, such as porphyra tenera (porphyra tenera) protein content of up to 47% of dry weight, is no less than meat nutritious food.
Seaweed (seaweed) Image source: wikicommons
Although the people of East Asia have a long history of eating seaweed, you may not know that the successful cultivation of seaweed by humans is only less than 70 years old. Before that, seaweed was almost a godsend.
During the Song Dynasty (976-983), fishermen in Pingtan, Fujian Province, invented the "vegetable altar farming method", that is, sprinkling shell ash water on the reef suitable for the growth of seaweed to disinfect and kill other algae so that wild seaweed can grow attached to it. During the Edo period (1603-1868), the Japanese would insert bamboo poles and nets in the tidal belt to make nori (hóng), and seaweed sometimes grew on the nori. This type of ancient technique is known as "natural seedling culture".
In Hiroshige Utagawa's "100 Views of the Famous Edo", the nori appears in the ukiyo-e painting "Minami Shinagawa Tsukisu Coast". Image source: wikipedia
However, although the ancients knew that nori produced "seeds" in the spring, these "seeds" would grow to bamboo poles and reefs in the autumn, but no one knew where they were in the summer, no one knew where they were, nori farmers had never seen the "seeds" of nori, everyone knew almost nothing about the life cycle of nori, and the breeding method was completely trial-and-error blind guessing, so the annual seaweed harvest was completely dependent on the sky.
This makes seaweed an extremely valuable ingredient. In our country nori was once a tribute. The "Pingtan County Chronicle" records: "During the Song Dynasty, the altar seaweed served as a tribute. In Japan, seaweed was once called "Bodacao", which means that raising seaweed is the same as gambling, or "transporting grass", and harvesting means luck. In 702, the Japanese Asuka period code "Daiho Ordinance" stipulated that seaweed was a state-owned asset, and the possession of seaweed was taxed.
During World War II, Japan's nori luck ran out. In the 1940s, Japan's seaweed industry was hit hard by typhoons and pollution from artificial fertilizers into the sea, and the harvest of seaweed as a whole was unusually low, and sushi lost its soul. By 1951, almost no seaweed could be eaten in japan. Similar to seaweed farmers, botanists at that time knew almost nothing about the life cycle of seaweed, so they couldn't help it.
But then, because of a scientist who can't get a salary, the fortunes of seaweed are reversed in an instant. In the 1950s, the people of East Asia ushered in a good day when they did not have to look at the sky and eat seaweed. The scientist was Kathleen Mary Drew-Baker.
Kathleen mary drew-baker. Image source: wikipedia
In 1922, Drew graduated first class from the University of Manchester and later became a lecturer in botany at the University of Manchester, where he studied algae. But more than 70 years ago, Universities in the UK had a rule that married women were not hired. So when Drew married another faculty member at the school, Henry Wright-Baker, she was stripped of her teaching position and had to work as an unpaid researcher.
Despite not being paid, Drew's interest in research remained undiminished. At the time, her research topic was a delicious seaweed, porphyra umbilicalis.
Umbilicalis (porphyra umbilicalis). Image credit: nicolas blouin, univ. of maine
Umbilical nori is a close relative of porphyria yezoensis and porphyria tenera, which are common in East Asia. The United Kingdom is rich in navel-shaped seaweed, and in Wales and other places, people will grind this seaweed into powder, which is used to bake bread or make soup.
Welsh specialty laver bread laverbread. Image source: saga.co.uk
One day in the 1940s, Drew noticed on the edge of the beach that there were often strange things mixed in with empty shells, and it turned out to be fans, pink filaments. She took these strange fans back to the lab to observe them with a microscope.
She noticed that this little pink thing mixed in wasn't it the creature that botanists called conchocelis. Previously, botanists thought that shell algae were a class of single-celled organisms unrelated to seaweed, growing in discarded shells.
Chitomacyloids, later known as Chitinella filaments (aunt color). Image source: California academy of sciences
Drew found that this fan number is particularly high in the summer, and this time period happens to be the season when nori mysteriously disappears. She understood, good fellow, shell algae is not another species at all, this is nori when she was a child.
Let's take a look at the perverted life of nori. It turns out that the seaweed we usually eat is the form of the leaf-like body before we are born and before giving birth.
Phylloscopic laver produces sperm and eggs. After the sperm eggs of seaweed are combined, they produce fruit spores (not pronounced in Sichuanese), which is the fertilized egg of seaweed. The fruit spores grow into the north nose of laver, the vermicelli of Drew's discovery, the shell spotted algae, which scientists now call the shell spotted algae filament.
However, the nori north nose, the filaments of the algae must be in the shell to continue to grow, because under natural conditions, the exposed filaments of the algae can easily be eaten by herbivores.
Before Drew, people knew about seaweed (blue), and the seaweed life cycle (red) that Drew elucidated. Image credit: Deepseanews
The chitinous filaments also give birth to children, which produce a second type of spore of nori, the shell spores. (One is called fruit, one is called shell, very easy to remember.)
The seaweed that people catch in the sea is actually the shell spores of seaweed. In winter, shell spores are slapped by waves on reefs or farmers' bamboo poles. Each shell spore does meiosis and develops into a seaweed leaf, which is the seaweed we eat.
See here you should understand, in fact, the small pink shell algae hiding in the shell has a complete chromosome, it is equivalent to the complete state of nori, and the seaweed we usually eat is actually only half of the chromosome.
With half a chromosome and a full set of chromosomes at a time in life, the unbridled life form of nori is known as alteration of generations.
Drew put the fruit spores on a clean shell, and sure enough, the shell grew shell algae, proving that the shell spot algae came from seaweed. In 1949, Drew published the relationship between shell and seaweed on Nature.
At the same time, because Drew and Soyoshi Segawa, a researcher at Kyushu University in Japan, knew him about it. Segawa Soyoshi read this article and finally realized that it turned out that nori was always raised in the street because there was no important seaweed nursery- shells. Soyoshi Segawa later informed the Kumamoto Prefecture Fisheries Test Site of the incident.
Shell algae are artificially cultured with shells.
Later, Japan developed a method of industrial production of seaweed - artificial seedling picking technology: first in the nursery room with oyster shells or clam shells to cultivate shell spots, and then the shell spores spit out by shell spots are glued to the net, and then put into the sea water to grow, and in the winter to collect the nets for seaweed. Around the same time, the South China Sea Institute of Oceanography of the Chinese Academy of Sciences also developed a similar artificial seedling picking technology for seaweed based on Drew's research.
Glue the net to the shell spores, then put the net into the seawater, and after 1-2 months, you can collect the net to catch seaweed.
In a 2014 interview with BBC, Alistair Munro, an economist at the Japan Graduate School of Policy Studies (GRIPS), said that without Drew's findings, the Japanese economy could have stalled after the war. Sadly, Drew died of cancer in 1956 and was unable to travel to East Asia to see modern seaweed farms.
In honor of Drew's kindness, people engaged in the seaweed farming industry voluntarily donated money and in 1963, a monument to Drew was built at the corner of the Sumiyoshi Shrine in Uto City, Kumamoto Prefecture, the main seaweed producing area, and honored her as "Mother of the Sea" (海の母).
Monument to Drew in Uto City, Japan and introduction to the Droo Festival. Image source: wikipedia
In addition, on April 14 every year, Uto City holds a festival to commemorate Droo (Drew Festival). At Drew Festival, people hang the flags of The United Kingdom and Japan, and also wear the degree uniforms and degree hats that Drew wore when he earned his degree. In 2001, the centenary of Drew's birth, her children were also invited to the celebration.
Artist Owen Davey painted drew a Drew print for the University of Manchester.
Who would have guessed that a small shell that an unpaid researcher picked up on the beach out of curiosity would make her a goddess on the other side of the ocean.
The three East Asian countries hold hands, and whoever eats seaweed is a friend. The three brothers with water in one garment all have a friendship with seaweed. The three giants of iron-blooded Confucianism all rely on the sea mother to bless them. The yield is not high, what to fear, ten thousand pieces of red algae in Drew.
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Unlabeled image source network.
References are stored in graphite:
https://shimo.im/docs/dvxjtdgpyjrwx9qk/