Animals are our good friends, and many of our inventions are inspired by animals. I don't know if you have observed it carefully, but there are many mathematicians among animals. Spider is a famous geometer, and its "gossip net" is complex and beautiful. This symmetrical octagonal geometric figure is difficult to draw even by senior carpenters with rulers and compasses. Coral, known as "algebraic genius", writes a "calendar" on itself: it "carves" more than 300 patterns on the body wall every year. Ant is a great computing expert. The British scientist Hinston did an interesting experiment: he cut a dead grasshopper into three pieces, the second piece was twice as big as the first piece, and the third piece was twice as big as the second piece. Forty minutes after ants discovered these three foods, the first grasshopper gathered 28 ants, the second grasshopper gathered 44 ants, and the third grasshopper gathered 89 ants, the latter group was about twice as many as the former group. It's amazing that ants have such high computing power. Bees, great architectural experts. The beehive built by bees is hexagonal, and the angle is very accurate. This structure not only saves materials, but also is strong and solid, which is really wonderful. Designers have racked their brains to reduce the weight of satellites and rockets. Finally, they were inspired by the construction of a beehive, which consists of tens of thousands of hexagonal prisms of equal size, and the bottom is closed by three congruent diamonds. Their acute angles are 70 32', which is both light and strong. Designers imitate the structure of beehives, make them into light metal with high melting point and high strength, and sandwich them into layers with two metal plates, just like beehives. This reduces the weight of satellites and launch vehicles and saves a lot of money. A large number of satellites and spacecraft of Cross adopt honeycomb structures. It is scientifically called "natural close packing system"