Recently, "Flavor of the World 2", which dominates the popularity of food documentaries, has once again made foodies rejoice. Among them, the second episode of "Crab Rampage", which was jokingly called "One Hundred Ways to Die of Crabs" by netizens, blue crabs, butter crabs, hairy crabs, blue crabs and other varieties of crabs, in the hands of different chefs, made different delicacies.
(Hairy crab, from Tencent video screenshot)
When we lament the delicacy of crabs, we can't help but wonder how long this species, which is clad in sharp armor, domineering, and warm nephrite on the inside, has existed on the earth?
Crabs , belonging to the order Brachyura , are a class of decapods , and are sometimes considered a suborder due to the controversial classification in the phylum Arthropods.
(Crab specimen in the museum)
Short-tailed animals are commonly known in Chinese as crabs or crabs, and are written in ancient Chinese books as 㻟 or crabs. Most of the animals in this class live in the sea, but many also live in fresh water or on land.
(Land crabs living in Central America)
The crab's first pair of feet becomes a pair of often very large claws (some species of claws are asymmetrical, such as tidal waves)
(Scissor hand posing tide, chelating asymmetry)
Many other animals with similar names – such as hermit crabs, king crabs, porcelain crabs, horseshoe crabs and crab lice – are not real crabs.
(King Crab)
(Hermit Crab)
Crabs are omnivorous animals that feed mainly on seaweed, but sometimes they also eat microorganisms, insects, shells they take off, etc., depending on the species. If there happens to be a more nutritious food, crabs will scramble to eat it. Examples include dead fish, dead shrimp, carrion, anglers' bait, and even food waste discarded by humans.
Crabs generally have exoskeletons with chitin as the main constituent substance, and a pair of crayons. The smallest known crab in the world is the bean crab, which is only a few millimeters long, while the largest Gan's giant crab (also known as the Japanese spider crab) can reach up to 4 meters in size with its legs spread.
(Bean crab, tiny size)
(American Museum of Natural History Gan's giant crab specimen, leg extension 3.8 meters)
Male crabs and female crabs have more obvious differences in body surface characteristics. Males have larger claws, a feature that is particularly pronounced in the tide, which is a huge claw that plays a huge role in attracting partners. Another obvious difference is its abdomen, most male crabs have a narrow triangular abdomen, while the female crab's abdomen is larger and more rounded, one of the main reasons is that the female crab's abdomen has the function of storing eggs.
(The difference between male and female crabs)
(Female crab laying eggs)
Evolutionary history of crabs
The oldest surviving crab fossil was found in the Jurassic Period.
(Crab fossils from the Jurassic era found in Argentina)
Some scholars have also proposed that the Carboniferous organism Imocaris may also be a primitive crab, but it is uncertain because only its carapace has been found.
(Imocaris carapace fossil, Carboniferous, published in 1984)
Crabs began to radiate around the world during the Cretaceous Period, which may be related to continental drift, and until now, crabs have spread all over the world. Due to the structure of the leg joints, crabs walk sideways relatively quickly, so "rampage" has become the characteristic of most crabs.
But there are also some crabs, such as some creatures of the frog crab family, that travel straight, or backwards. The Dawn Crab family, Pike Crab family and some other crabs also swim.
(The upper sea pike crab, the last pair of feet has evolved into a flat paddle shape to assist swimming)
Crab habits - brave and fierce, not afraid of pain
Crabs are lively creatures with complex habits. According to research, crabs communicate mostly by making sounds or waving large claws. Crabs, on the other hand, are generally aggressive, especially males who often fight for mates and food.
(Fighting Crabs)
When a crab challenges its kind, it walks up to the other and raises its claws in protest. In the face of such provocations, the smaller crabs will immediately come down and take the initiative to surrender and retreat, while the unbelieving crabs will directly fight.
In a sense, crabs are natural fighters, they have a very aggressive big, but no pain. Even if the jaws are broken, they can grow again.
Crab and humans – food
Although it is not known who was the first to eat crabs, after the precursor, crabs slowly became one of the important food sources for people around the world. According to statistics, 20% of the crustaceans crustaceans caught, farmed and consumed in the world every year are crabs, with a total of 1.5 million tons.
(Velvet pike crab caught in Scotland)
Crab is rich in high-quality protein, crab meat is more delicate, muscle fiber contains more than 10 kinds of free amino acids, of which glutamic acid, proline, arginine content is more, for postoperative, post-illness, chronic wasting diseases and other people who need to supplement nutrition is of great benefit. Crabs are low in fat but high in vitamins A, E and B.
(Meat on crab legs)
And the fate of Chinese and crabs is even longer. Zheng Xuan of the Eastern Han Dynasty notes "Zhou Li Tianguan Kuren": "The thing that recommends shame is the meal of the four hours, the fish of Jingzhou, the crab of Qingzhou." Lü Chen explained in the "Zi Lin": "Xu, crab sauce also." The Sui Dynasty Emperor took crab as the first food, and during the Song and Yuan Dynasties, it was popular to eat "hand-washing crab", which was marinated with salt, wine, orange peel, pepper and other spices. In order to eat crabs, caoshu in the Ming Dynasty used three pieces, such as hammers, knives and tongs, to deal with the hard shell of crabs. In the late Qing Dynasty, Suzhou people made a tool specially used to eat crabs, "Crab Eight Pieces", "Crab Eight Pieces" once became the dowry of Suzhou people's married women.
(Eight pieces of crab)
In addition to China, there are also crabs in other parts of the world.
(Japanese crab meat dish)
The world's largest crab importers and regions are Japan, France, Spain, the United States, Canada and Portugal, which are therefore also major crab consumers.
Mencius once said, "If a few poppies do not enter the pond, the fish and turtles cannot be eaten; the axe and pounds enter the mountains and forests at the time, and the timber is invincible." Humans also need to fish rationally for this delicious species that once coexisted with dinosaurs on earth and on the table of modern humans.
(Some of the images are from Wikipedia and the Internet)
bibliography:
Carrie E. Schweitzer & Rodney M. Feldmann. The oldest Brachyura (Decapoda: Homolodromioidea: Glaessneropsoidea) known to date (Jurassic). Journal of Crustacean Biology. 2010, 30 (2): 251–256. doi:10.1651/09-3231.1.
Frederick Schram & Royal Mapes. Imocaris tuberculata, n. gen., n. sp. (Crustacea: Decapoda) from the upper Mississippian Imo Formation, Arkansas. Transactions of the San Diego Society of Natural History. 1984, 20 (11): 165–168.
David Adam. Scientists say lobsters feel no pain. The Guardian. 2005-02-08.
Editor: Che Yueyi
Proofreader: Zhang Song