Avocado (Top)
Most farmers grow spring and autumn wheat, followed by lentils, chickpeas or dried peas. Rotation helps control pests, but just as importantly, peas and beans hold nitrogen in the soil, which naturally provides fertilizer for the grains to be planted next.
This combination of grass and legumes is as old as agriculture, and it is always used repeatedly when people domesticate plants wherever they are. In the Fertile Crescent, chickpeas, lentils and dried peas all develop alongside barley wheat. In China, early rice farmers later grew soybeans, red beans and mung beans. Maize and spotted beans are paired with Central American, while African millet and sorghum always work closely with cowpeas and fallen peanuts.
This synergy isn't just a great growing method, it extends to people's tables, making starchy grains and protein-rich legumes perfectly complement each other in taste and nutrition. Because a combination of rice and beans, or a combination of lentils and barley, can provide "complete protein." The basic nutrients that may be lacking in a particular grain are generally found in the accompanying legumes, and vice versa. But significant differences in the composition of grains and legumes also raise fundamental questions about seed biology.
Chinese are very familiar with soybeans, which are native to China and have been cultivated in China for five thousand years, and they can squeeze out soybean oil, and the residue left over from the oil can be used as feed for poultry and livestock. Soybeans can be used to make a lot of food, such as fried beans, soy milk, tofu, dried tofu, etc., especially valuable is that tofu food can eat the taste of meat, many temples use beans to make imitation meat flavor vegetarian food, which also brings a lot of comfort to the poor people for thousands of years.
Soybean seedlings (above)
Since grass is so successful in nature and so useful to people, seed equipping a starch-rich energy bank is obviously a pretty good evolutionary way. So why don't all plants do this? Why do beans and nuts store energy in the form of protein and vegetable oils? Why does a single palm nut contain more than 50% saturated fat? Why do jojoba seeds drip liquid wax?
The starch of grasses may be a staple food for humans, and their starch-filled seeds are easily converted to sugar. But plants obviously have many other ways to feed their seeds and for us, such as cocoa beans, squeezing the cocoa beans with a hot press, and more than half of its mass will drip in the form of cocoa butter, a fat with important characteristics, which is solid at room temperature and liquid above 32 degrees Celsius, so it melts in the human mouth. Cacao trees grow in forests in southern Mexico, Central America and the Amazon. The Maya and Aztecs discovered that it could extract a stimulant-acting energy drink from cocoa beans, which in their language means "food of God."
Today, cocoa beans are loved by people all over the world, and people spend a lot of money on it. Ecologically, it makes sense to have a fat, greasy seed, and like the coumba tree or avocado, the cocoa tree seed evolved the ability to germinate and grow in the dark forest. In the dark forest, the seedlings must store huge amounts of energy to survive, but strangely, why is this energy stored not in the form of starch but fat?
Cocoa Tree (Part 1)
Cocoa Beans (Part 1)
Similarly, the coconut is also a mysterious plant, and it exists in many parts of the tropics, proving that it is a very successful plant. It was so successful because its fruit functioned as a floating chunk of seed. Each buoyant shell surrounds a fist-sized nut with only one nutrient-rich liquid in it, coconut water, which is academically known as "non-celled endosperm."
When the seeds of the coconut tree mature, much of its liquid hardens into a solid endosperm called the copra. This well-known white pulp not only makes sugar, but also adds flavor to Filipino stews, Jamaican bread and South Indian chutney.
Coconut milk is obtained by squeezing juice out of the pulp, which is a basic ingredient in the preparation of curries and sauces throughout the tropical coastal region. As long as it is simple processing, you can squeeze more than half the weight of coconut oil from the coconut trunk, it is one of the world's top five vegetable oils, but also a commonly used additive, from margarine to sunscreen and other products will use it, coconut use is widely known by Malaysian islanders as "a tree with a thousand uses".
Coconut (above)
When a ripe coconut falls off a tree, it always falls to the beach first. Wild coconut trees are salt-tolerant and heat-tolerant and adapt to flowing soils, qualities that help it thrive along tropical beaches, while tides and storms regularly carry their seeds into the ocean. Once floating on the surface of the ocean, a coconut can survive for at least three months, and it will float for hundreds of miles, perhaps even thousands of miles, riding the wind and waves. During this time, the endosperm continues to coagulate, but there is still enough coconut water to help the seeds germinate after rushing to the dry sand. With liquid endosperm keeping the interior moist and with the power of a coconut rich in vegetable oils, a young coconut can grow continuously for weeks without the help of any external resources. In the markets of the tropics, we often see people selling sprouted coconuts as seedlings, and the newborn leaves on these seedlings are already several feet tall.
The coconut tree's aquatic adaptability sets it apart, but that still doesn't explain why its seeds need such rich and greasy nutrients. After all, if you put starch or cocoa butter into that huge fibrous shell, they can float too.
When collecting information, it was quite interesting to see a piece of content, especially the following:
Coconut water is delicious, but its shell is very hard, often need to be cut open or holes in something like a knife or axe to drink coconut water. But if you've just eaten gum, you can use it to drill a hole in the coconut.
If you don't practice it, no one may believe it, but someone may have seen such a video, that is, someone took the chewing gum that he had eaten into the shape of a nail like a big and small nail, and then took a hard coconut and smashed it on it, and then a miraculous thing happened, the coconut was actually stuck to a hole by the gum, and the shape of the gum did not change much. What's going on?
In fact, this is a phenomenon that often occurs when non-Newtonian fluids are hit by rapid impacts! The so-called non-Newtonian fluid refers to a fluid that does not meet Newton's law of viscosity experiments, and refers to a fluid whose shear stress and shear strain rate are not linear.
Non-Newtonian fluids and Newtonian fluids are different, most pure liquids such as water, alcohol, light oils, low molecular weight compound solutions and low-speed flowing gases are Newtonian fluids, while concentrated solutions and suspensions of polymers are generally non-Newtonian fluids.
However, non-Newtonian fluids are actually very common, such as polyethylene, polyacrylamide, rubber solutions, various engineering plastics, melts of chemical fibers, solutions, etc., are non-Newtonian fluids. For example, petroleum, mud, coal water slurry, ceramic pulp, pulp, paint, ink, toothpaste, high sand water flow, mudslide, mantle, etc. are also non-Newtonian fluids. Tomato juice, starch liquid, egg white, fruit syrup, yogurt, soy sauce, condensed milk, agar, potato syrup, chocolate sauce, dough, rice flour balls, as well as surimi, minced meat and other surimi food materials in food are also non-Newtonian fluids.
Chewing gum can open the coconut, because the non-Newtonian fluid has the characteristics of "strong and strong" under rapid impact, because the morphological change of the non-Newtonian fluid is very slow, the worse the fluidity of the non-Newtonian fluid, the slower the time of its morphological change, when the coconut is smashed down, the chewing gum shape is simply too late to change, the force time on the coconut has ended, so the coconut can be pushed out of a hole.
Plant evolution seems illogical in many ways, and starch, oil, fat, protein, and other energy strategies appear to be randomly distributed in the plant kingdom. These strategies have evolved to vary great degrees, as recently evolved species have the same basic way of storing energy as ancient species. To complicate matters further, seeds often contain several different amounts of energy, and the parent plant changes the proportion of energy depending on precipitation, soil fertility, or other growing conditions.
Plants that grow in similar environments or have similar growth processes do not necessarily rely on the same strategy. Grass seeds are known to be rich in starch, but the common weed in crop fields is an annual mustard called rapeseed, whose small seeds can produce large amounts of low-acid rapeseed oil.
Rapeseed (above)
A common principle, in the same case, stores oil and fat seeds that have the greatest energy. More energy is taken from lipids than from a whole bunch of starch. Seeds usually acquire this energy only after they have sprouted. Most species of seeds prepare enough sugar to trigger the growth of the embryos, and then begin a more complex process of obtaining the reserve energy.
Starch can be converted into sugar relatively easily, but converting protein, fat or oil into a form that is helpful to cells requires a series of processes. For this you can also see in marathons, the organizing committee will prepare bananas, cereal bars or jam sandwiches for athletes, rather than large chunks of bacon or a few glasses of olive oil. In terms of seed evolution, this approach focuses on the resources required for newly sprouted plants and their growth conditions.
Almonds (above)
However, while that could explain why seeds like cocoa beans and almonds that grow in forests use fat and oil to provide slow and stable nutrients for their own growth in the shade, it doesn't explain why mustard seeds in open fields grow rapidly using exactly the same substance.
We thought that seeds had perfected the "best" way to store energy, and after natural selection, many possibilities were eliminated, leaving only a few optimal survival strategies adapted to specific geographical environments. But the reality is much more complex and much more interesting, and like evolution itself, is an elegant and never-ending process of unfolding all possibilities. Just as a seed can equip its energy bank in different parts (cotyledons, endosperm, endosperm, etc.), energy can also come in many forms.
If they could only provide starch, there is no doubt that seeds would still be successful in nature, and we would still use them as a staple food on which we depend. But without oil, fat, plant wax, protein and other energies, seeds would not be so versatile and they would not be able to dominate so many terrestrial ecosystems.
People won't be able to get more than 45 percent of the world's protein from peas, beans and nuts. Nor can we enjoy fried food, walk on linoleum, paint our houses, lure rocket and racing engines, or marvel at the artworks of Rembrandt, Van Gogh, leonardo da Vinci. All of these activities rely on the oil in the seeds. Even the least common source of energy in seeds has valuable uses for humans.
The way the Ivory Palm of South America stores energy for seeds is by increasing the thickness of the cell wall inside the endosperm, and sometimes the cell wall even squeezes out the active substance inside the cell. As a result, its seeds are so hard that they can be cut and polished into buttons and jewelry, carved statues, or used instead of ivory to produce chess pieces, dice, letter-breaking knives, decorative handles, and delicate musical instruments.
Ivory Palm (Part 1)
There is also a magical plant called "guar gum", which is widely used in food manufacturing, and it can affect the texture of ice cream, gluten-free bread and motorcycle prices in northern India. Perhaps better than any example, it shows the diversity of energy seeds store and the unexpected ways in which they touch our lives.
Guar gum comes from a messy-looking guar bean that grows mainly in rajasthan, India's "desert state." Botanists classify it as endosperm-containing legumes, a species of plant that has very few plants whose seeds do not have huge cotyledons like beans, peanuts, and other legumes as we know them. Instead, the seeds of guar beans store energy in endosperms rich in highly branched carbohydrates. In the chemistry textbook schematic, the molecules look like a map of the Shanghai subway, but for guar bean seedlings growing in the Rajasthan desert, they are a simple and basic adaptive change.
Guar Bean Tree (Part 1)
These tissues are doubly protected, first of all, they can be broken down into food, becoming glucose for plants to grow. But they also form a protective, moist layer that surrounds the embryo. For this desert plant, this water retention skill transforms every rare and precious rainfall into a vital opportunity to sprout. This is a habit that has undergone many evolutions, locust beans can do it, fenugreek can do it, but it all appears in places with dry climates.
At first, guar beans were only used by locals to cook vegetables, and later when people realized that guar beans as a food thickener effect was 8 times that of starch, its fate changed, after extraction and purification, guar gum appeared in various products, this income alone, in 2000 India's guar beans export volume reached 280 million US dollars.
Guar gum is also used in oil drilling technology, and the millions of gallons of fracturing fluid pumped into the wells are a viscous mixture of water, sand, acids and chemicals, and only guar gum is bonded together, so farmers who grow guar beans make a lot of money.