So, what happened at the bottom of this cave? Gu Qingniao couldn't react a little, originally thought it was an ordinary trip, an ordinary adventure, but it turned out to involve so many things at once.

It's not that Gu Qingniao hasn't seen someone die, it's just that it's all what happened in the Gate of the Sky, and since then, although she has a little resistance to this kind of thing, but when these things are placed in front of her, she still can't help but feel a little uncomfortable.

Looking at the bones under this piece of sand, the ancient bluebird had a feeling of hair in his heart.

Lan Ling supported her slightly from behind and said, "These people seem to have been dead for a long time, probably from the same era as that tombstone. ”

"You mean, that tombstone is actually for these bones?" Gu Qingniao couldn't help but ask.

Lan Ling nodded: "There is this possibility." ”

A monument that stands in front of or behind a grave and is engraved with the name of the deceased and his deeds. [1] A memorial vehicle for the burial of the dead, generally made of stone, but also wood, metal, and other materials. In ancient China, "tombs but not graves" were only buried underground, and there were no tree signs on the surface. Later, there were graves with mounds on the ground, and there were tombstones. After a person dies, if they want to set up a tomb, most of them must have a tombstone. The inscription on the tombstone is generally engraved with the name, place of origin, achievements, date of death, name of the person who erected the monument and the relationship with the deceased. The inscription should be written with respect and affection for the deceased. In the twenty-second year of the Republic of China, "Henan Tongzhi, Sui County Interview Draft, Yuan Keli Tombstone": "Yuan Shangshu can set up a tombstone, in the south of (Suizhou) City, Sili Xu, Liudian Village East Xu. The stele is eight feet high, the upper cockroach, the lower scum, the height is about more than zhang, and it is still called the system. Chinese name Tombstone Material Stone, wood, metal materials, etc. Purpose Commemoration of the deceased Features Generally contains inscriptions Contains the name of the deceased, his experience and deeds, etc. Pinyin mù bēi Table of Contents 1 Origin 2 Uses 3 Form 4 Material 5 Inscription 6 Atmosphere 7 Type Origin Edit For the graves of funeral relatives, one or two generations can be remembered, but after three generations, it is not clear, especially after migration and war, where the ancestral grave is. How to solve it, people come up with many solutions. In the beginning, people were inspired by the wooden stakes used to hold the coffin rope when the dead were buried, and they inserted wooden stakes and bamboo poles in front of the tomb, tied them with fibrous things (paper or silk, etc.), and wrote the date and time of the deceased's birth and death, which was called "Mingjing" (or "Mingjing"). But it is easy to be damaged, so people think of another way: the rich and noble families use stone garden pillars instead of wooden garden piles, and the name of the deceased, the time of birth, and the official rank are engraved on the stone pillars. In order to engrave more words, its shape evolved into a square, rectangular, began to be buried in the tomb or outside the tomb, with reference to the house building, the top of the stele is added to the stele cap, decorated with carved moving, plant or landscape patterns, and the stele body is engraved with the resume of the deceased. It is marked as a single burial with wives, concubines, sons, daughters, etc. Attached to the inscription of the yin house (i.e. the tomb) feng shui geographical location orientation. (indicated by the sexagenary branch). Middle-class families can erect medium tombstones, and poor families can only erect small stone tablets with a name, or terracotta tablets or plant some kind of evergreen trees as a mark. As a result, tombstones have gradually been transformed from practical objects into cultural artworks, and their functions, forms, textures, and decorations have become more and more diversified. Celebrity tombstones pay more attention to the body of the stele mostly with high-quality stones such as Huagang rock, marble, etc., and there is a statue of the deceased on the top of the stele or a porcelain statue of the deceased inlaid in the center of the stele. The tombstone has become a "certificate of honor" and ornament that records the family lineage and meritorious deeds of the deceased. This is very much in line with the social customs of the Chinese people to glorify their ancestors, Ze and their descendants, and to pass through the ages. In order not to be protected from natural erosion and man-made damage such as wind, rain and sun, the tablet is erected outside the tomb, and the epitaph and inscription are buried in the tomb. Tombstones prevailed in the Han and Tang dynasties, and later became a fixed trend. UsageEdit First, the wooden tablet stands in front of the palace gate, so it is called "the palace must have a monument". This wooden stele is used to recognize the shadow of the sun, and from the yin and yang of the shadow of the sun, the change of the seasons can be measured; Second, the ancient temple in front of the monument, there are perforations on the tablet, which is used to tie the rope, tie the sacrificial livestock, and after the feast, pull out the animal for blood sacrifice; Third, the ancient stele was a tool for leading the coffin into the burial. Form Editing At the four corners or on both sides of the tomb, a wooden pillar with a round hole in the pillar is called "piercing". Then a horizontal log is erected in the middle of the two pillars, and a rope is wrapped around the wood, which can be used to put the rope and drag the coffin into the tomb like a wheel. After the burial, the wooden tablet is buried in the ground or placed next to the tomb. During the Spring and Autumn Period, the Son of Heaven had six fibers and four monuments, the princes had four fibers and three monuments, and the doctor had two fibers and two monuments. In the Zhou Dynasty, the Son of Heaven began to use stone tablets, and the princes also began to use stone tablets on weekends. The stone stele of the Zhou Dynasty was only used to lead the coffin into the cave, and the stele was not engraved with words. The Han Dynasty began to engrave the deceased's situation, such as name, date of birth and death, on the stele, and those with status began to erect the stele to pass it on, thus forming a tombstone, tomb table and other ceremonial culture. The tree stele is the focus of the tomb, according to feng shui, are oriented to the direction of the tombstone, which is an important part of the cemetery. The size of the tombstone, the size of the text, and the time when the tree monument was grounded should be carefully considered. In general, it is buried first, and then the stele. There are two reasons for this: first, after the burial, a period of time should be set aside for the combination of rain and soil, so that the imaginary square becomes a real square, which can avoid the depression of the ground when the tree monument is established; Second, after the burial, set aside a period of time for the family to consider the content of the inscription. Especially the evaluation of celebrities, the weight of the sentence should be carefully considered. For example, the Shunzhi Emperor who founded the Qing Dynasty was buried in the second year of Kangxi and erected a monument in the sixth year of Kangxi. The second generation of Kangxi Emperor of the Qing Dynasty, was buried in the first year of Yongzheng, and the monument was erected in the fifth year of Yongzheng. It is true that ordinary people also have those who are buried and erect monuments at the same time. The scale of the tombstone, limited by the traditional belief in feng shui, should be auspicious. It can be ruled with the help of a "feng shui ruler". The south has a "Dinglan ruler" to determine the good and the bad. One foot of Ding Lan ruler, about 38.1cm, divides one foot into ten grids, and notes one word, that is, wealth, loss, prosperity, death, official, righteousness, suffering, harm, Ding and other ten words. Among them, wealth, prosperity, official, righteousness, prosperity, and Ding belong to auspicious qualities, which can be selected according to the scale. And other unlucky losses, death, suffering, and harm, try to avoid. Nowadays, "Luban ruler" is widely used in civil engineering, especially when creating ancient wooden furniture, it is more followed by carpentry masters. On the Luban ruler, it is divided into two gears, the upper part is used for the yang house, and the lower part is used for the yin house. In each cm of the long tape measure, the auspicious and evil fortunes of Feng Shui are injected. In today's cemetery, the use of Luban ruler design, construction, pay attention to the auspicious numbers. For example, the size of the tombstone is usually 100cm high, 60cm wide and 8cm thick; The monument is 55 cm or 50 cm high, 80 cm wide and 8 cm thick. On the Luban ruler, it shows 100cm windfall and Shunke. 60cm into the treasure, windfall. 80cm Tiande. 55cm Daiki. 50cm into the treasure, Nafu. 80cm Caiwang、And brother。 Material editing is usually natural stone or artificial stone, with marble granite as the preferred material. Inscription editing The size of the inscription engraved on the tombstone should also conform to the auspicious number on the Luban ruler. Usually the large characters are between 10cm or 10.5cm, and the small characters are between 3cm or 4cm. 10cm into the treasure. 10.5cm Nafu. 3cm wealthy. 4cm denko. The size of these words is in harmony with the proportion of the monument, and it means auspiciousness. The family of the owner of the tomb can find psychological solace in it. The stone of the tombstone is selected, and the marble and white marble of the past cannot withstand the wind and rain and is very easy to weather. It has now been replaced by a series of granites with exquisite materials, brightness and hardness. Among the colorful and solid granite, the more popular ones are Indian red, pearl white, and Shanxi black. Indian red symbolizes noble, gorgeous, fiery years, and brilliant careers; Pearl white symbolizes purity, elegance, gorgeous life, and endless sorrow; Shanxi black symbolizes the **, dignified, immortal spirit, and deep nostalgia. The writing of the tombstone is relatively rich in content. Including feng shui conditions, place of origin, name, identity, date of birth and death, descendants, monument erector, date of burial or reburial. 1. Feng Shui, the left side of the tombstone is called the dragon edge, which is an important part of the tombstone. Here it is necessary to write the mountain direction and the mountain direction linearity, and the gold line. For example, "Liqi Shan Ding divides the meridian into two points with propylene gold." Its purpose is to inform future generations that if they encounter the flood of natural disasters or the damage of war, future generations can still find the original feng shui direction and re-erect the monument according to the feng shui situation text on the stele. "(Yuan Keli) the day of the burial is Chongzhen Ding Chou December 27, the tomb is in the south of the county, go to Zuqi Erli Xu, that is, the road of the construction, and the purpose is the same tunnel! 2. Origin: In cemeteries with a large number of immigrants, especially those who have died in other places, the names of the provinces, cities, and counties of origin should be engraved on the most conspicuous parts of the left and right corners of the tombstones, and some only the names of regions and villages should be engraved. This is the nostalgia for the hometown, and it also provides convenience for future generations and relatives and friends to find a tomb when they sweep the sacrifices. "According to the form: the public can be established, the word is polite, and the alias is Jiehuan." The ancestors lived in Fengyang, the ancestor Rong, and at the beginning of the country, he repeatedly transferred the city to guard hundreds of households with military exploits, which is now Suiyang Weiye. Then he migrated to Sui and replaced him with virtue. 3. Name, written in the center of the tombstone. This is called the "middle list". When writing the name of the tomb owner, the number of words is associated with good luck in feng shui. In order to respect the elders, many respectful words were added in the past, such as the father called the examination and the examination, the mother called the concubine and the concubine, the man added the prince and the prince, and the woman added the family and the widow. And the number of words is applied in a cycle according to the five words of "life, old age, sickness, death, and suffering". Among them, the words "sheng" and "old" that fall on sixth, seventh, eleventh, twelfth, sixteenth, and seventeenth are auspicious. If it falls on the word "disease", it is medium, and if it falls on the word "death" and "suffering", it is unlucky. Therefore, when planning to win the list, try to use the numbers in the auspicious format as much as possible. For example: "Cheng Xinjiang Society 19th Emperor Feng Zheng Dafu Kao Quanyuan Qiu Mansion Junjia City", up to 21 words, just in line with the "life" character, the most auspicious. If the names of the husband and wife are written on the tablet, they are arranged according to the left and the right, with the man on the left and the woman on the right. In the twenty-second year of the Republic of China, "Henan Tongzhi, Sui County Interview Draft, Mausoleum": "Yuan Shangshu Keli tomb is in the south of (Suizhou) city five miles, Luozhuang South Xu, the tablet is published in the tomb of Yuan Jiehuan (Yuan Keli), the senior doctor Zhengzhi Shangqing, the military department of Shangqing. 4. The date of birth and death is written on both sides of the middle list, still according to the left of the man and the right of the woman, and it is best to write the year, month and day completely. Because of the passage of time, the household registration has been cancelled and passed from generation to generation, and it is very difficult to find the date of birth and death of the ancestors. Ming Wang Duo's "Prince Shaobao Bingbu Shangshu Festival Huan Yuan Gong Shendao Monument": "On October 11, the seventh season of the emperor's reign in the world, Yuan Gong (Yuan Keli) finally returned home. 5. The person who erects the monument, including children, relatives, friends, and groups, should write it on the tiger side of the monument, that is, on the right side. The child should be written in full, and the deceased child can be framed around the name. It is still arranged from left to right. There are also those who do not want to reveal their names, and they can write that their children stand or bow, and worship and stand together. "Daming Chongzhen is ten years old, Ding Chou December 27, the male Shu (Yuan Shu) weeps blood and accepts stones." 6. The time of building or rebuilding the tomb is engraved on the tiger side of the stele. There are many words that record time in China, including the Common Era, the lunar calendar, and most of them write the winter solstice and Qingming in the season. The date is also mostly used in dry branches. The A, B, C, D, E, G, XIN, NON, and Gui in the heavenly stems are combined with the sub, chou, yin, mao, chen, si, wu, wei, shen, unitary, shu, and hai in the earthly branches to represent the days or months in the calendar. Such as Jiazi, Bugly ....... There are also literati who divide the four seasons of spring, summer, autumn, and winter equally among the twelve months, with each month having a different name. For example, January is called Meng Chun, February is called Zhongchun, and March is called Ji Chun; April is called Mengxia, May is called Midsummer, and June is called Jixia; July is called Mengqiu, August is called Mid-autumn, and September is called Jiqiu; October is called Mengdong, November is called midwinter, and December is called Jidong. There are also flowers and trees named for the twelve months, such as the tombstone plum moon in January, the apricot moon in February, the peach moon in March, the acacia moon in April, the durian moon in May, the liyue moon in June, the melon moon in July, the laurel moon in August, the chrysanthemum moon in September, the sandalwood moon in October, the Jiayue moon in November, and the oak moon in December. On tombstones, it is also common to see "Gu Dan", "Ji Dan", and "Ji Day", which are not specific dates. "Gu Dan" comes from the "Book of Songs", Gu Shanye, Dan Ming also, that is, the meaning of good days. And "auspicious day" and "auspicious day" are only taken from their auspicious meanings. They are all used to make up the number of words when arranging the number of auspicious words. In addition, when they can't remember or can't remember the month and day of birth and death, they often write the auspicious month and auspicious day, and the family of the tomb owner gets psychological comfort. Epitaphs, including epitaphs, epitaphs and tables. The Eastern Han Dynasty began to erect the monument in front of the cemetery. The stele is engraved with the official title, name, and date of birth of the tomb owner. Later, the family history and life achievements of the tomb owner were also engraved on the tablet, and they were praised. In the Wei, Jin, and Northern and Southern Dynasties eras, officials repeatedly banned the erection of monuments. They believe that "since the Han Dynasty, the world has been extravagant in sending people to death, and they have made more stone rooms, stone beasts, inscriptions and other things." In the tenth year of Jian'an (205), Cao Cao ordered that no thick burials should be allowed, and it was forbidden to erect monuments. Emperor Wu of the Jin Dynasty enjoyed the fourth year (278 years) and edicted, "This stone beast tablet table, both private praise, prosperity and hypocrisy, hurt wealth and harm people, nothing greater than this, a ban on it." "Due to several prohibitions on the erection of the monument, the tombstone went underground, resulting in an epitaph. Between the prevalence of the Tang Dynasty and the early Qing Dynasty, a large number of epitaphs were unearthed. The epitaph is made up of two square stone tablets, called a one-in-one. The top is a tomb cover, and the text is relatively simple. Generally, the dynasty, official title and surname are engraved in regular script or seal script. Such as "the epitaph of the late Zhang Fujun of the Tang Dynasty", "the epitaph of the late Yongwang of the Tang Dynasty", "the epitaph of the princess of the late Song Dynasty", and "the epitaph of Jun Zheng of Yongshou County of the Song Dynasty". The perimeter of the text is engraved with exquisite flower and bird ornaments. On the other side, the name of the owner of the tomb is inscribed. The origin and a large text describing his life deeds, and finally there are inscriptions, most of which are rhymes in four words. Each epitaph has historical, literary, calligraphy, and artistic content, and to varying degrees, reflects the cultural characteristics of that era. "Xianxian Yuan Gong, a great man in the world." It came out at the right time, and it was a treasure. Luan Jiejian Department, Fengming Bai Mansion. The lungstone is not wide (jue), and the garment is mended. The Shinto monument originated from the Northern Dynasty, which paid special attention to Feng Shui, and Feng Shui masters took the south as Shinto. In fact, Shinto is the tomb road to the south, so the monument erected on the Shinto road is the Shinto monument. In the Tang Dynasty, the whole was called a rectangular stele, and between the ring head or a square circle, the upper small and the lower large were called Jie. The use of steles is distinguished by rank. Officials above the fifth grade can erect a monument, and officials above the seventh grade can set up a monument. In the Qing Dynasty, officials above the fifth grade used the turtle head stele, and officials below the fifth grade used the square head of the round head. In principle, no monuments are allowed to be erected in front of the tombs of ordinary people. But the social atmosphere is uncontrollable, but the stele erected by the common people is smaller, there is no pedestal, and only the name and year of birth and death, and the person who erected the stele are written on the tombstone, and the biography and epitaph are not written. The Shinto monument of the imperial tombs of the past dynasties has no limit on scale, and its monument is tall and majestic. And there is a very spectacular stele tower, only take the Jingling of the Kangxi Emperor of the Qing Dynasty as an example. On the Shinto, there is a monument of sacred virtue and divine merit, commonly known as the big monument, in which there is a monument of the dragon's head and turtle. Emperor Kangxi was the longest reigning emperor in China, because of his merits and many words, with the approval of Emperor Yongzheng, he set up two stone tablets in the stele tower, engraved with Manchu on the left and Han on the right. Under the stele pedestal is the dragon's footage, and the stele head is engraved with double dragon play beads and the seal word of "Daqing Jingling Shengde Shengong Tablet". The text on the stele body is prefaced, narrative and inscription. Although there are beautiful words to praise the emperor, as well as real historical materials in all aspects of society at that time, there is still a certain historical value. In the tombs of the emperors, there are no Shinto monuments and Ming Lou monuments. The Shinto monument is set on the Shinto in front of the mausoleum, and its monument tower is commonly known as the small monument tower. The stele is still the dragon's head and turtle, but the shape is smaller than the stele of the holy virtue. Its inscription is engraved with the emperor's temple number and all the nicknames. The temple number is a special name when the emperor was enshrined in the Taimiao after his death. The nickname is the title that evaluates the deeds of the emperor during his lifetime. In addition to the inscription of Emperor Shozuhito on the Shinto monument, there are also some beautiful words before and after death, and the emperor can enjoy 22 characters. Ming Tower is the highest building in the mausoleum area, located in front of the tomb head (treasure top), in the Ming Building, its dragon head square stele, also called the holy name stele. It is engraved with Manchurian and Mongolian characters as "Mausoleum of Emperor Shengzuren". In short, the supremacy of imperial power is highlighted everywhere in the imperial tombs. And the emperor also advocated "ruling the world with filial piety". This may also be a kind of royal filial piety. In modern cemeteries, most tombstones only engrave the name of the tomb owner, the year of birth and death, the person who erected the tomb, and the time when the monument was erected. There are also words such as "blessed descendants" and "blessed descendants" engraved on the back of the tombstone, and short words such as "remembrance" and "mourning" are engraved on the tomb cover. On the tombstones of celebrities, there is a brief biography of the owner of the tomb. There are also living people, with heart, affection, tears, blood, and love written sentences. It condenses the long road of life and expresses the infinite human feelings. There are sad sorrows, happy memories, inspiring words, and heroic words to warn future generations. This text, which blends the feelings of the living and the dead, is full of the philosophy of life, and the true meaning of life is expressed between the lines, and it is an encyclopedia that can never be finished. i) Monuments. The front of the tombstone indicates the name of the person in the tomb, the person who erected the tomb, and the time when the tombstone was erected. Most of these monuments were erected by the descendants of the deceased. There are also students who erect tombstones for teachers, sons-in-law for fathers-in-law, husbands for wives, wives for husbands, and friends. The title of the deceased in the tombstone inscription is summarized as follows: ii) A tombstone that introduces the inscription on the life of the deceased. This kind of inscription generally includes name, place of origin, family history, experience, writings, date of death, burial place, and finally inscription, mostly rhyme, three words, four words, five words, seven words or sassy body. Most of them were commissioned by the descendants of the deceased. Such as Han Yu's "Liu Zihou's Epitaph". There are also more simple inscriptions and short epitaphs that introduce the deceased.

Bones (bo

e，skeleto

): Hard tissues in or on the surface of humans or animals. There are two kinds of endoskeleton and exoskeleton, the skeleton of human and higher animals is in the body, which is composed of many bones, called endoskeleton; The hard shells of arthropods and mollusks and the scales and nails on the body surface of some vertebrates (such as fish, turtles, etc.) are called exoskeletons. Bones are commonly referred to as endoskeletons. [1]

Bones are the hard organs that make up the endoskeleton of vertebrates, and their function is to move, support, and protect the body; production of red and white blood cells; Stores minerals. Bones are made up of a variety of different shapes, with complex internal and external structures that allow bones to remain rigid while reducing weight. One of the components of bone is mineralized bone tissue, which is a hard, honeycomb-like three-dimensional structure inside; Other tissues include bone marrow, periosteum, nerves, blood vessels, and cartilage. The bones of the human body play the role of supporting the body and are part of the body's locomotor system. Adults have 206 bones. Bones are generally connected by joints and ligaments.

Evolutionary competition

The fossils of the Idiacara fauna, first discovered in Australia, are 570 million years old, and they are molluscs without hard bones. The earliest known animal fossils with a hard exoskeleton (shell) are the so-called "small-shell fossils" at the very bottom of the Cambrian period, which are conical or shaped tubules as small as a few millimeters long, and their mineral composition is carbonate or phosphate, which can be said to be the earliest ossification of animals.

Amazingly, the Cambrian Beginning Cyanobacteria and

Cyanobacteria

Cyanobacteria

Calcification has also been observed in some other algae. The phenomenon of skeletal (calcification) in animals and plants at about the same time has aroused the interest of paleontologists and sedimentologists, and has led to a discussion and debate about the causes of ossification. Most paleontologists and sedimentologists agree that changes in the chemistry of neoproterozoic seawater contributed to the evolution of bones. For example, the British sedimentologist Ridi

g believes that from the end of the Proterozoic to the beginning of the Cambrian, the magnesium-calcium ratio m(Mg)/m(Ca) in seawater decreased, and the dolomite in carbonate rocks decreased, and calcite increased, which was related to the emergence of calcified cyanobacteria. At the same time, the sea water at the end of the Proterozoic was rich in phosphate, which is related to the appearance of some phosphate crustacean fossils. However, when Russian scholars analyzed carbonates from the end of the Proterozoic (Wende period) to the early Paleozoic, they found that the ratio of magnesium to calcium did not change significantly. On the other hand, the American scholar G

otzi

ge

(1989) suggested that the calcium content of seawater decreased at the end of the Proterozoic, and the calcium ions of seawater gradually decreased from the saturated or supersaturated state of the Early Proterozoic to the state below the saturation point of the late Neoproterozoic and early Cambrian. Therefore, the cause of ossification may not be related to the chemical environment of seawater, but to the organism itself.

The appearance of the exoskeleton of animals with the calcification of cyanobacteria.

The appearance of the exoskeleton of animals with the calcification of cyanobacteria.

The emergence of animal exoskeletons and calcification of cyanobacteria in the early Cambrian period. a. Early Cambrian calcified filamentous cyanobacteria Gi

va

ella； b~d. Small shell fossils at the top of the Sinian Dengying Formation (near the Cambrian base) in the Xiling Gorge of the Yangtze River: S. rotundifolia

(b) Three-grooved Araba A

aba

itest

isulcatus (c) and Si of the Si tube

otubulitessp．

At the end of the Proterozoic, multicellular benthic plants and phytoplankton flourished, and with the first adaptation of animals to radiation, the biodiversity of marine ecosystems increased greatly, the food chain level increased, and the competition between species intensified. Some scholars believe that carnivorous and herbivorous animals may appear in ecosystems, and that squastursification is first and foremost a response to new relationships within ecosystems. In other words, the calcification of cyanobacteria and other algae plants may be a protection against feeding by herbivorous animals, and the production of mineralized shells of some small invertebrates may also be an adaptation to predators. If the above explanation is correct, then we can say that bones originally evolved as a protective (defensive) system. The almost simultaneous skeletalization of animals and plants may be associated with the complication of interspecific relationships within marine ecosystems from the end of the Proterozoic to the beginning of the Cambrian.

Chemical composition

From the point of view of chemical composition, it is possible to distinguish between bones with inorganic minerals as the main component and bones with organic matter as the main component. Most invertebrate bones are mainly composed of calcium carbonate (calcite, aragonite), and chitin exoskeletons are found in higher invertebrates such as arthropods. Chitin is a polysaccharide (aminopolysaccharide) type of organic matter, and the exoskeleton of arthropods (crustaceans, insects, etc.) is mainly composed of chitin and mineralized (calcified phosphate) collagen fibers (a protein). The supporting base of terrestrial plants is lignin, which is a poly aromatic compound. In terms of the order of evolutionary appearance, bones dominated by calcium carbonate, calcium phosphate and siliceous inorganic components appeared earlier, followed by chitin bones, and then calcified collagen fibrous bones. The lignification of plants is relatively late.

The structure of the organism is more in line with the principles of mechanics. Regarding the importance of support, we can cite the following items: (1) the soft tissues and soft bodies of multicellular organisms are difficult to increase in size without a hard support system; (2) The support system enables the important organs in the body to be reasonably arranged in space, and maintain a relatively stable spatial position, so as to achieve the overall functional harmony; (3) The support system enables the development of the animal's locomotor organs, and ultimately enables the animal to be removed from the water environment

Human bone editing

Skeletalization is the basis for the complexity of biological structure, and the skeletal system is the limiting factor for the evolution of biological morphology. Bones are the hard organs that make up the endoskeleton of vertebrates, and their function is to move, support, and protect the body; production of red and white blood cells; Stores minerals. Bones are made up of a variety of different shapes, with complex internal and external structures that allow bones to remain rigid while reducing weight. One of the components of bone is mineralized bone tissue, which is a hard, honeycomb-like three-dimensional structure inside; Other tissues include bone marrow, periosteum, nerves, blood vessels, and cartilage

1. Bone "supporter": calcium

When calcium intake is insufficient, calcium in the bones is released into the blood to maintain blood calcium concentration, resulting in lower and lower bone density and more and more osteoporosis, which in turn can lead to fractures, bone degeneration or rickets in children.

Nutritional strategy: Some people have made statistics that the average person can only consume 250-350 mg of calcium in a day's diet, which is far from the daily calcium intake recommended by the Chinese Nutrition Society of 800-1000 mg.

Experts point out that when you are young, you should eat more calcium-containing foods in order to store enough calcium for your bones. Under normal circumstances, eating more milk, soy products, kelp, shrimp skin, etc., can meet the needs of normal people for calcium supplementation.

When cooking, you can add some vinegar to help dissolve calcium and help absorption. People who like to eat fatty meats, fried foods and other fatty foods, as well as those who like salty foods, should pay special attention to calcium supplementation, because fats and salt will inhibit calcium absorption.

2. Bone "gas station": vitamin D

It can promote intestinal calcium absorption, reduce kidney calcium excretion, and act like a gas station, continuously replenishing calcium into the bones. If vitamin D is missing, the stiffness of the bones decreases, resulting in "hypochondria". Young children often have underdeveloped skull and thoracic cage and are prone to rickets; The bone strength of pregnant women and the elderly in the lower limbs, pelvis, etc., will be reduced.

Nutritional strategy: 90% of the body's vitamin D is synthesized through its own skin through ultraviolet radiation in the sun; The remaining 10% is consumed through food, such as mushrooms, seafood, liver, egg yolks and lean meats.

Experts point out that the safest, most effective and economical way to supplement vitamin D is to bask in the sun. American researchers recommend that when the weather is fine, it is enough to expose more than 40% of the skin without sunscreen for two hours before and after noon every day. For people who have been working in office buildings for many years, the sunlight through the glass cannot achieve the effect of supplemental D, so it is best to do more outdoor sports during the holidays.

3. Bone "concrete": proteins

In bones, 22% of the components are protein, mainly collagen. With protein, human bones can be like concrete, hard but not brittle, tough, and able to withstand the impact of external forces. Amino acids and peptides in proteins favor calcium absorption.

If the long-term protein intake is insufficient, not only will the person's new bone formation lag behind, but it will also easily lead to osteoporosis. Studies have found that people who do not like to eat meat and soy products and lack protein for a long time are prone to hip fractures.

Nutritional strategy: Eat foods rich in collagen and elastin, which are most beneficial to bone health, such as milk, eggs, walnuts, meat skin, fish skin, pig trotter jelly, etc. Normal people do not need to take extra eggs**, etc.***. Excessive protein intake is not good for bones, which will increase the acidity of the body's blood, accelerate the dissolution of calcium in bones and the excretion of calcium in urine.

4. Bone "defender": magnesium

60%-65% of the body's magnesium is found in bones. Experts say magnesium plays an important role in the formation of new bone. Although the amount of magnesium in bones is low, once deficient, it can make bones brittle and more prone to breakage.

Long-term magnesium deficiency can also lead to vitamin D deficiency, which can affect bone health. Women who eat a diet low in magnesium also have lower bone density.

Nutritional strategy: Seaweed, whole grains, almonds, peanuts, and spinach, among others, are rich in magnesium. Eating peanuts 2-3 times a week, 5-8 grains each time can meet a person's magnesium needs; Drinking plenty of water can also promote magnesium absorption.

5. Bone "stabilizer": potassium

Every cell in the human body contains potassium, and bones are no exception. Its main role is to maintain acid-base balance, participate in energy metabolism and normal neuromuscular function, which is essential for the growth and metabolism of bones. A study published in the American journal Environmental Nutrition also noted that potassium prevents calcium loss and makes bones stronger.

Nutritional strategy: To replenish potassium, eating more fruits such as bananas, oranges, plums, raisins, vegetables such as tomatoes, potatoes, spinach, yams, and seaweed foods such as seaweed and kelp is the safest and most effective method. Orange juice, in particular, is rich in potassium and replenishes water and energy. Potassium supplements are best not to be taken lightly as it may be bad for the heart.

6. Bone "additives": vitamin K

Just as food requires certain additives, bones also need vitamin K to activate osteocalcin, a very important protein in bones, thereby improving the bending resistance of bones.

Harvard University research has shown that women with low vitamin K intake increase the risk of osteoporosis and femur fractures. Dutch studies have found that vitamin K supplementation can promote bone health in children and reduce the occurrence of arthritis.

Nutritional strategy: The darker the green color of the vegetable leaves in the diet, the higher the vitamin K content. Eating only 500 grams of vegetables a day, including more than 300 grams of dark green leafy vegetables, can effectively prevent vitamin K deficiency.

People who take antibiotics for a long time may have the balance of intestinal flora disrupted, affecting the synthesis of vitamin K, so special attention should be paid to eating more green leafy vegetables. In addition, vitamin K is a fat-soluble vitamin, and it is best not to eat raw vegetables when supplementing, but to sauté them with seasoning oil.

7. Bone "scavenger": vitamin B12

Vitamin B12 is the only vitamin that contains the mineral phosphorus, which plays an important role in maintaining bone hardness. It acts as a "scavenger" to remove homocysteine from the blood, protect bones and prevent osteoporosis and even hip fractures caused by excessive homocysteine.

Nutritional strategy: Animal liver, shellfish, lean beef, whole-grain bread and low-fat dairy products are all foods rich in vitamin B12. However, it is difficult for the elderly to absorb vitamin B12, and plant foods (except for spirulina and other algae) do not contain vitamin B12, so people over the age of 50 and vegetarians can take supplements appropriately, and the standard daily intake is 2.4 micrograms.

Bone identificationEdits

How to find clues to determine gender, age and other information from bones, rescue excavation of an Eastern Han Dynasty tomb in Xigaoxue Village, Anfeng Township, Anyang County, Henan Province, China, the owner of the tomb is likely to be Cao Cao, a hero of the Three Kingdoms period. One of the evidences given by archaeologists is that they deduced from the skeleton that one of the remains in the tomb was male and died at about 60 years old, which is very similar to Cao Cao's 66-year-old death. During the excavation, in addition to the suspected skeleton of Cao Cao, experts also found two female skeletons buried together.

Determine gender

There are many ways to determine sex using bones, which can be generally divided into two categories: comparative observation and instrumental measurement. The former refers to the determination of sex by observing the morphological differences of bones with the naked eye. Generally speaking, males have coarse bones, rough surfaces, obvious protrusions at muscle attachments, thick bone density, and heavy bones; Whereas, women's bones are weaker, the bone surface is smooth, and the bone is lighter. However, the bones of women who have been physically active for a long time are not significantly different from those of men. In this case, it can be judged by the pelvis, and since the woman is responsible for the task of childbearing, the size of the upper pelvic mouth (the size of the inside of the pelvis) is larger. This difference is evident from the fetal period and is more pronounced after sexual maturity. In addition, there are also some gender differences in the skull, sternum, clavicle, scapula, and long bones of the limbs. The latter refers to the use of a bone measuring instrument to measure the length, width, height, angle and thickness of the remains. Compare the obtained data with the male and female means; Or according to the corresponding mathematical means, the data is substituted into the regression function for calculation. And then determine the gender.

Given that many factors such as nutrition, health status, geography, and gender can affect bone morphology, many skeletal features, such as the presence of ossification centers and the healing of epiphysis, change regularly with age. For example, at the age of 30~40, the ossification center of the costochondral increases, and the sternal stem and sternal body heal, and at the age of 40~50, the sternal body and the xiphoid process heal, and the larynx and costal cartilage begin to solidify, and when you reach more than 60 years old, the cartilage of the whole body will ossify.

For the age determination of adult skeletons, it is more common to compare the morphological changes of the bones by observation. In childhood, bone tissue has more organic matter, which makes bones more tough and less hard. In adulthood, the proportion of inorganic matter gradually increases, accounting for about 70%, at this time the bone is not only hard, but also elastic and tough, and in old age, the inorganic component is further increased, the bone becomes more brittle, and at the same time, under the action of bone hyperplasia and absorption, the shape of the bone has also undergone corresponding changes. When estimating the age of bones in adulthood and beyond, looking at the pubic symphysis is one of the best methods. The error can be controlled within 5 years to infer the age based on the skeletal characteristics here, and the error can even be narrowed to about 2 years if the age of death is between 20~40 years old. With the advancement of technology, the analysis of the age characteristics of the pubic symphysis with the help of quantitative models can also make the results more accurate. In addition, the sternum also has the characteristics of regular changes with age, and the accuracy of estimating age is second only to that of the pubic symphysis.

In archaeological excavations, skulls are generally relatively well preserved, so there are many clues to age that can be found here. The skull is a structure of 29 bones, which are connected by sutures between the skulls except the mandible. The presence of these tiny gaps allows the skull to slide slightly. Although the rate of healing of most skull sutures varies greatly between individuals, it can still provide valuable information for age classification. For example, the healing time of the basal suture of the skull is relatively stable, generally at the age of 20~25 years, and the owner of the bone can be judged whether the owner of the bone is an adult by observing the fusion of the basal suture. When a person enters the old age (50~60 years old), the bone suture is completely fused and dissolved. Therefore, based on this information, when an experienced archaeologist obtains a skull, he can roughly determine the age of the death of the owner of the skull with the naked eye alone.