There are approximately 1.5 million known animal species. Can be divided into invertebrates and vertebrates. Scientists have identified more than 46,900 species of vertebrates. Including fish such as carp and yellow croaker, reptiles such as snakes and lizards, as well as familiar birds and mammals. Fish
Characteristics: Aquatic animals (can only live in water). The skin is covered with scales and is a cold-blooded animal. A cold-blooded animal that has fins (can swim in water) and uses gills to breathe. In vitro fertilization, mainly oviparous, some viviparous and ovoviviparous. There are many types of fish, mainly divided into two categories: cartilaginous. For example: shark. Characteristics: tough skin, extremely small scales, no swim bladder, asymmetrical tail fin up and down, five pairs of gills, and no gill cover. Teleosts Example: Horsemouth Characteristics: The skeleton is hard bone, the skin has many mucus glands, is covered with bone scales, and has a swim bladder.
Amphibians
(Amphilia) Characteristics: Need to spend their childhood in water. It has a skeletal structure adapted to living on land, has limbs, moist skin, and many glands. The body has no scales or body hair. The tongue is bifurcated, inverted, and can extend outward. Fish
Mating and fertilization occur in the water. Larvae breathe through gills, while adults breathe through the skin, lining of the mouth and lungs. Classification of amphibians without tail Example: Toad Characteristics: It has a skeletal system adapted to life on land, with a divided body, trunk and limbs. The forelimbs have four toes, the hind limbs have five toes, and there are webs between the toes. The hind limbs are suitable for swimming and jumping, but have lungs. The main respiratory organs are the inner wall of the mouth and the skin. Existing example: Salamander Characteristics: It has a skeletal system adapted to life on land and is an amphibian with a slender body and a tail. Unexplained example: Salamander
Reptiles
Characteristics: Terrestrial animals. The skin is covered with scales or scutes. It has a waterproof outer skin that prevents water loss. It is a cold-blooded animal (relying on external temperature or heat source to change its body temperature). Mainly distributed in Warmer areas of the earth. Internal fertilization, oviparous or ovoviviparous. Eggs are laid on land, and the eggs are wrapped in waterproof shells. Classification of reptiles testbyfindwo Pedopods Example: Turtle Characteristics: Has a hard shell. The upper and lower jaws do not have teeth, but they have Horny sheath. Egg-laying. Can be classified into terrestrial, aquatic or marine life. Apodoid example: Cobra Characteristics: No limbs, shoulder girdle and sternum. No movable eyes, face and external ear holes. The tongue is bifurcated at the end and has strong telescopic force. The skin has scales and can swallow prey larger than the diameter of its own body. The snake's organs are all specially adapted to grow and its left lung has degenerated. The snake sheds its skin regularly, allowing it to continue to grow and facilitate reproduction.
Birds
Characteristics: The whole body is covered with feathers, the body is streamlined, and there is a horny beak. The eyes are on both sides of the head, and the neck is long and flexible and can rotate 270 degrees. The forelimbs are specialized into wings. The hind limbs have scaly skin and four toes. They are warm-blooded animals (they can generate heat through their own physiological processes, and they can maintain a high and constant body temperature even if the outside temperature is very low). The average body temperature is about 10 degrees higher than that of mammals ( Average 42 degrees). Oviparous. 1. Main features (1) The body is covered with feathers, has wings, and can fly. The skin is thin and soft, allowing for vigorous muscle movements. (2) The metabolism is strong and the body temperature is constant. A high and constant body temperature promotes the metabolism in the body. Constant temperature reduces the animal's dependence on external temperature conditions, gaining the ability to be nocturnal and survive on polar continents. (3) Have a developed nervous system and senses. The brain, cerebellum, and midbrain of birds are very developed. The cerebral hemispheres are larger, mainly due to the enlargement of the striatum at the base of the brain. In birds, the striatum is a high-level part that manages movement and is also related to some complex life habits.
Experiments have shown that when part of a bird's striatum is removed, its normal excitement and inhibition are destroyed, its vision is affected, and its courtship, nesting and other habits are lost. The cerebral cortex of birds is not developed, but the cerebellum is very developed, which is related to the coordination and balance of birds' flight movements. (4) Have relatively complete reproductive methods and behaviors (nesting, incubating eggs and brooding). 2. Classification of Aves (1) The main characteristics of Ratites are: strong hind limbs, flat chest, no keel, and no ability to fly; feathers are distributed all over the body, and there is no distinction between feathered areas and bare areas. The barbules do not have hooklets, so they are not capable of flying. Form pinnae. Common species include ostriches and chicks. (2) Penguins are medium- and large-sized birds that live in diving and have a series of characteristics adapted to diving life. The forelimbs are fin-shaped and suitable for paddling. It has scaly feathers (the rachis is short and the pinnae are narrow), evenly distributed on the body surface. The tail is short, the legs are short and moved to the back of the body, and there are buns between the toes, which are adapted to swimming life. When walking on land, the body is nearly upright and sways from side to side. The developed subcutaneous fat helps maintain body temperature in cold areas and in water. The bones are heavy and not inflated. The sternum has a well-developed keel protrusion, which is related to the forward stroke. Swim fast. The distribution of this order is restricted to the Southern Hemisphere. Represented by the King Penguin. (3) Phytophorax usually has well-developed wings, is good at flying, has a developed keel, and the last 4 to 6 tail vertebrae heal into a coccygeal bone. They generally have inflatable skeletons, well-developed feathers, and form pinnae. The body surface is divided into feathered areas and bare areas. Most male birds do not have mating organs. There are many species of birds in this general order. For the convenience of research, their groups can be discussed from two aspects. One aspect is that according to the ecological type, it is divided into seven ecological types: wandering birds, wading birds, quails, doves and pigeons, climbing birds, raptors and songbirds. Wandering birds: flat and broad beaks or long pointed ones, short and webbed legs, powerful or vestigial wings. Wading birds: beaks are thin and long, feet and toes are very long, webs are not well developed, and wings are powerful. Quail: The peck is short and strong, the feet and claws are strong, and the wings are short and round. Dove: short beak, waxy film at the base, short and strong feet, and well-developed wings. Climbing birds: strong beak, short and strong feet, opposite toes, and well-developed wings. Bird of prey: a strong hook-shaped beak, powerful feet, sharp hooked claws, and powerful wings for flying. Songbirds: Beaks have different shapes, short and thin legs, and relatively developed wings. Another aspect is to divide it into several orders for research based on morphological and structural characteristics. Here are some common ones. Pelicanformes: forward in all directions, with full puffs everywhere; the end of the mouth is hook-shaped, with a well-developed throat pouch, the chicks are late adults, nomadic birds, such as cormorants, etc. Craneformes: long neck, long beak, long legs, three toes in front of one in back, and four toes on the same plane. The young birds are late-growing crows, wading birds, common species include egrets, etc. Anseriformes: flat beak with thickened beak and ctenoid-like protrusions on the edge; short legs moved backwards, three toes in front and one in back, webbed between front toes, male wings often have wing mirrors; male birds have mating apparatus ; The fledglings are precocious birds and wandering birds. Common species include swans and mallards. Falconiformes: They have sharp hooks in their beaks, well-developed claws, and strong flying power. They have keen vision and are birds of prey. Their chicks are late adults. Common species include kites, kestrels, golden eagles, etc. Galliformes: strong body; short beak, cone-shaped; short round wings, good at walking; male birds have fleshy crests on top of their heads and brightly colored feathers; the behavior during the breeding period is complex, quail and chickens, and the young birds are early adults. Such as brown-eared pheasant, golden pheasant, etc. Craneformes: long beak, long neck and long legs, three toes in front and one behind, underdeveloped webs between the toes, the hind toes are higher and not on the same plane as the other three toes, the young birds are precocious birds, wading birds kind. Common species include red-crowned cranes, gray cranes, etc. Columbine order: short beak with wax film; four toes are on the same plane, short and strong feet, good at walking; crop is well developed, the chicks are late adults or early adults, doves and pigeons. Common species include rock pigeons, hairy-legged sand grouse, etc. Owl-shaped order: The bill and claws are strong and hooked; the head is large, the eyes are large and forward, and the feathers around the eyes form a face plate; the ear holes are large, with ear feathers, and the hearing is keen; the fourth part can be reversed backward; young birds are late bloomers Birds belong to the raptor category. The main species include long-eared owl, short-eared owl, etc.
Birds of prey: The beak is cone-shaped, suitable for pecking wood; the tongue has a long horny hook; the toes are two in front and two in back; the young birds are late adults and climbing birds. Common species such as spotted woodpeckers. Passeriformes: The syrinx and song bones are well developed; the toes are three in front and one behind, on a flat surface, suitable for nesting. The young birds are late adults and are songbirds. Common species include skylarks, barn swallows, etc.
Mammals
Features: There is a spine in the body connected by many vertebrae; The body is covered with hair, and there is an oral cavity for chewing and digestion, which can improve the intake of energy and nutrients; Viviparous birth (Except the platypus and echidna), suckling; homeothermy. It can maintain a relatively constant body temperature even when the environmental temperature changes, thereby reducing dependence on the external environment and expanding the distribution range; the brain is enlarged, the brain is quite developed, and the intelligence is The adaptability to the environment exceeds that of other animals; the inner limbs are strong and sensitive, and have the ability to move quickly; the left and right chambers of the heart are completely separated; the teeth are divided into incisors, canines and cheek teeth. Classification of mammals 1. Main characteristics (1) The whole body is covered with hair and has the ability to move quickly on land. Hair is unique to mammals, and mammals generally molt twice a year: in spring and autumn. Molting is mammals' adaptation to seasonal changes. (2) Oral chewing and digestion occur. The digestive tract is highly differentiated, the digestive glands are relatively developed, and the digestive enzymes are diverse. Mammalian teeth are divided into incisors (incisors), canines (canines) and molars (molars). Tooth shape and number of teeth are one of the basis for classification of mammals. (3) The body temperature is constant and dependence on the environment is reduced. Mammals
(4) have highly developed nervous systems and senses, and strong coordination capabilities. The main manifestations of the mammalian nervous system are the increase in the size of the cerebrum and cerebellum, the aggregation of nerve cells, and the thickening of the cortex. Wrinkles (sulci and gyri) appear on the surface. (5) Viviparous and lactating, the offspring survival rate is high.
Prototherian characteristics are oviparous and the eggs are shelled. (Example: platypus) Metatherian characteristics do not have a true placenta, and the baby is born in the pouch. (Example: kangaroo) Eutherian characteristics have a placenta, and the fetus is born after it is fully developed , accounting for the vast majority of mammals, and are divided into fourteen categories. Insectivores (for example: moles) Scales (for example: pangolins) Chiropterans (for example: bats) Lagomorphs (for example: rabbits) Rodents Classes (e.g. rats, porcupines) Dentodonts (e.g. anteaters) Carnivores (e.g. lions, dogs, pandas) Pinnipeds (e.g. sea lions, seals, walruses) Sirenia (e.g. manatees) Whales Classes (e.g. dolphins, whales, proboscis (e.g. elephant)) Perissodactyla (e.g. zebra, rhinoceros) Artiodactyla (e.g. hippo, cow, pig, deer, camel) Primates (e.g., orangutan, monkey , human) Example: Characteristics of a lion: It is a cat in the order Carnivora. It is a large mammal with retractable claws, good at jumping, well-developed canine teeth, and good at ambush other animals. Example: Characteristics of an elephant: It is the largest terrestrial animal in existence. The ears are wide and flat, and the nose is very long, which can help with feeding. The body hair is degraded, and there are thick elastic tissue pads on the soles of the feet to support the weight of the body. The upper incisors are particularly developed and grow outside the body. The food is mainly plants. Example: Characteristics of anteaters : Two to three fingers of the forelimbs are particularly long, used for digging ant nests. They have no incisors, a long tube-shaped snout, and a long sticky tongue that can adhere to termites. The tail is long and hairy. It lives in grassland swamps and is good at swimming. It feeds on termites. They feed on ants. For example: Characteristics of bats: Specialized forelimbs with extremely long finger bones. There are thin and tough wing membranes between the finger bones and the sides of the body and hind limbs, which serve as flight organs. The hind limbs have claws that can be used to perch upside down. The sternum is protruding and the clavicle is well developed. , to facilitate flying. Most bats like to eat insects and are good at catching insects in flight, and a few eat fruits. Example: Characteristics of dolphins: Marine mammals, and there are also freshwater species. Dolphins are toothed whales, with streamlined bodies and necks. The head cannot be distinguished, and the cervical vertebrae are healed. The head is pointed and long, with an endoplasmic dorsal fin. The forelimbs are specialized into a broad paddle shape. There are no hind limbs, and the tail is long and has a horizontal forked caudal fin. Example: Characteristics of apes: The thumb is opposite to the other fingers. Suitable for climbing and holding objects. The clavicle is well developed, the body is hairy (except the palms), the fingers have nails, the brain and sensory organs are developed. The eyes are forward, and there are bony eye sockets. The behavior is close to humans.
No spine Animals
Classification of arthropods: Crustaceans: shrimps, crabs. Arachnids: spiders, scorpions. Insects: butterflies. Myriapods: centipedes. Thoughts: Looking for animal species and photos At that time, I spent a lot of time and energy, but I think it was all worth it. Because I read a lot of books and catalogs about animals and insects, and found it very interesting and learned a lot about animals. I also learned that zoologists are Classification is based on the different characteristics and living habits of animals. The largest terrestrial animal is the extinct tyrannosaurus, the largest now is the elephant, and the smallest is the amoeba that can only be seen with a microscope. I learned about amphibians again It turns out that they grew up in water when they were young, and then lived on land when they grew up. Some animals I used to classify as the same kind, but now I know that they are the second kind of animals. I also realized that everything we eat is different. They are living things, and all animals eat living things. Most animals are useful to us humans, but many animals are on the verge of extinction because we capture and kill them, especially mammals. In order to balance the ecology of nature, we Don't cut down trees at will, care for nature. Don't harm animals, because all animals are living animals like humans. There are 42 phyla in the animal kingdom 1. The Protozoa phylum is all single-celled animals and is the most primitive animal. Among them The ones we are familiar with include Euglena and Paramecium 2 Rhombozoda An endoparasitic animal with a simple structure, there are not many recorded species 3 Orthoptera Animals similar to rhombids 4 Porifera is also called Spongezoa.
Sponges are primitive multi-celled animals. 5 Platycozoa. So far, this phylum has been exclusively dominated by one animal, Filarialis~~~It’s so awesome that I have to admit~~ 6. Archaeozoa. As the name suggests, “ancient” means this type of animal. They are extinct. "Cup" means they look like cups. 7 Coelenterate phylum. There are polyps, jellyfish, sea anemones and corals here. They are very familiar. I won't go into details. 8 Ctenophores are also classified into this phylum. The phylum Coelenterata, as the class Ctenophora 9 The phylum Platyhelminthes contains planarians, trematodes, tapeworms and other parasites we often hear about 10 The phylum Intozoa Marine benthic animals with cylindrical or long sac-shaped bodies 11 Glossata The phylum Micrognathia is a newly discovered group of animals in 1994. Humans know very little about them. 13 Nemertea is slightly higher than Platyhelminthes. Similar animals 14 Gnatozoa is very small and lives in the fine sand of shallow seas. Not much is known about it. 15 Nematoda is a huge family, including roundworms that many people have in their stomachs. 16 Gastrochaeta A group of animals with cilia on the ventral surface of the body 17 Rotifera is a small phylum that is similar to protozoa 18 Nematoda A group of animals similar to nematodes 19 Branchiozoa are marine benthic animals that live in cold water near the poles , there are very few recorded species 20 Kinorhynchids are similar to gill draggers 21 Acanthora is a group of animals with a snout at the front of the body 22 Armored phylum is a new phylum discovered only in 1983, and is currently not accurately classified 23 Phylum Annelidae Moss-like small animals 24 Phylum Annelida Earthworms, leeches, lugworms... all have annular bodies, need I say that? 25 A recently discovered group of animals in the phylum Cyclostomia 26 The phylum Asterostomata is similar to the phylum Asterostomata 27 The phylum Mollusca contains a large number of common animals, which I will explain in detail later 28 The phylum Molluschia is extinct 29 Lobopods, Cambrian anomalocaris, etc. 30 Tardigrades are a very strong group of animals that can endure high temperatures, absolute zero, high radiation, vacuum and high pressure. 31 Onychopods have a worm-shaped body and cylindrical legs. It has claws at the end and is almost extinct. 32 Arthropods account for more than two-thirds of the animals in the animal kingdom. Leave it to the following to introduce this huge family of amphibians
33 Brachiopods. Sometimes you will find them at street stalls. Some shell-like fossils seen on the Internet are the remains of this type of animal. 34 The Exozoa and the Endozoa were once the same phylum, collectively known as the Bryozoa, but they have now been separated. 35 The Phylum Erythrozoa is another very small phylum, and only one phylum. There are more than 10 animals, all of which are marine benthic animals. 36 The Archaeozoans were extinct long ago in the explosion of life 530 million years ago. They were only discovered in recent years. 37 The Echinoderms are a phylum we are familiar with, including starfish. , sea urchins, sea cucumbers and crinoids 38 Bruchizoa are non-parasitic animals without mouths and digestive tracts. They live in the deep sea and their taxonomic status is controversial 39 There are only 2 species of Heterovortica, which are distributed near the Baltic Sea and have been considered Platyhelminthes. and molluscs 40. There are only about 50 species of Chaetognathia, which are still marine animals. 41. Hemichordates have worm-shaped bodies. Some people classify them into the phylum Chordata. 42. All vertebrates in the phylum Chordata
Edit This section Reproduction and Development
Almost all animals engage in some type of sexual reproduction. Mature individuals are diploid or polyploid. They have specialized germ cells that undergo meiosis to produce either smaller, swimming sperm or larger, immobile eggs. The sperm and egg will combine to form a fertilized egg and develop into a new individual. Many animals are also capable of asexual reproduction. This may occur in parthenogenesis (where mature eggs are produced without mating), or in some cases of reproduction via fragmentation.
The fertilized egg initially develops into a small ball, called an embryo, where it undergoes reformation and differentiation. Within the sponge, the embryonic larvae swim to a new location and develop into a new sponge. In most other groups, the embryo undergoes more complex rearrangements. The embryo initially becomes integued to form the gastrula with a digestive cavity and two separate germ layers - ectoderm and endoderm. In most cases, there is also a mesoderm in between. These germ layers then differentiate into various tissues and organs. Most animals use energy from sunlight indirectly to grow. Plants use sunlight to convert simple sugars in a process called photosynthesis. It starts with carbon dioxide and water. After photosynthesis, the energy of sunlight is converted into chemical energy bonded in glucose, and oxygen is released. These sugars are then used as building materials for growing plants. When animals eat these plants (or eat other animals that eat plants), the sugars produced by the plants are used by the animals. These sugars are either used directly to help animals grow, or they are broken down to release stored solar energy for energy for animal activity. This process is called glycolysis. Animals that live near hydrothermal vents and cold seeps on the ocean floor do not rely on solar energy. Instead, chemosynthetic archaea and bacteria form the base of their food chain.
Edit this section Classification level naming model method and identification
1. Prairie tortoise Clawed tortoise is a tortoise that lives in inland grassland areas. The carapace is 12-16 cm long and 10-14 cm wide. The head and limbs are yellow; the head is small, with symmetrical large scales on the top; the beak edge is serrated. The center of the scute is brown-black, the edge is yellow, and there are concentric rings. Each limb has four claws, and there are no webs between the fingers and toes. There are hard large scales on the forearms and shins, and a cluster of cone-shaped large scales on the back of the thigh. It is a national first-level protected animal. 2. Giant salamander The giant salamander is the largest of the existing urinary orders, and can be more than 1 meter long. The head is flat and blunt, the mouth is large, the eyes are underdeveloped, and there are no eyelids. The front part of the body is flat, and gradually turns to side flatness towards the tail. There are obvious skin folds on both sides of the body, the limbs are short and flat, the fingers and toes are five in front and four in back, and are slightly webbed. The tail is round, with fins on the top and bottom of the tail. The body surface is smooth and covered with mucus. The back of the body is mixed with black and brown-red, and the ventral surface is light in color. It is a national second-level protected animal. 3. Loris. The loris is small and slow-moving. It is a lower-level monkey with a body length of 32-35 cm. Two small ears are hidden in the furry round head; the eyes are round and big. The limbs are short, thick and equal in length, the second toe still retains a hook, and the tail is short and hidden in the hair. The back of the body is brown-gray or orange-yellow, with a tan ridge extending from the top to the base of the tail in the middle. The ventral surface is brown, and the eyes and ears have dark brown ring spots. There are also giant pandas, golden monkeys, white-tip dolphins, Chinese sturgeons, etc. in our country.
Mexican Vaquita Habitat: Gulf of California Remaining population: 200 to 300 It is a rare whale species that is endangered in the world. The number of Mexican vaquita itself, and being trapped in fishing nets is one of the reasons. The main reason for extinction. Cross River Gorilla Main habitat: Nigeria and Cameroon Remaining: Less than 300 A species thought to be extinct in the 1980s is still alive today. Hunted for food and squeezed out of their habitat by development, they may not last long. Sumatran tiger Habitat: Sumatra, in Indonesia Remaining: Less than 600 This small tiger has lived only in Sumatra for millions of years, so it is difficult to escape human expansion. Most of the survivors are protected, but about 100 still live outside the reserve. Primordial animals began to be protected. It remains in serious danger, but its numbers rose in 2003 for the first time in decades. Black-footed ferret Habitat: Great Plains of North America Remaining: 1,000 The only ferret on the American continent, they are the most endangered mammal. In 1986, there were only 18 individuals left, but the species' numbers are rebounding.
Bornean Pygmy Elephant Habitat: North Borneo Remaining: 1,500 individuals About 20 inches (50 centimeters) shorter than the Asian elephant, the Borneo Pygmy Elephant is also more docile. The decline in palm plantations has left them living in crowded spaces. Giant Pandas Habitat: China (Qinling Mountains, Sichuan) Remaining: less than 2,000. Loss and fragmentation of habitat are the main reasons for the endangered status of giant pandas. Captive breeding and help from species conservation hope to save giant pandas from extinction. Polar Bears Habitat: Arctic Circle Remaining: Less than 25,000 Long-term human development and poaching threaten polar bears' survival, but climate change and loss of sea ice are now becoming the main causes of their decline. Mekong Giant Catfish Habitat: Southeast Asia Remaining in the Mekong Region: Hundreds are particularly prized for their size (the largest ever found was 646 pounds, or 293 kilograms) and are now protected in Thailand, Laos and Cambodia species, but fishing continues. Purple Marsh Crab Purple Marsh Crab Found only in the wetlands of Upper Guinea in West Africa, purple crabs live in muddy holes in marshes that remain moist even during the dry season. The original living specimens, these semiterrestrial air-breathers, were collected in 2005. The recent discovery of a new population of this elusive crab led to its conservation status being reclassified from "critical" to "endangered" on the 2008 Red List of Endangered Species. Parachute Spider Rameshwaram Parachute Spider Restricted to a few plantations on the island of Rameshwaram and nearby mainland India, the Rameshwaram Parachute Spider is a critically endangered wolf spider and a threatened species on the 2008 Red List. The number of spiders is probably less than 500, and the woodland that serves as their habitat has been destroyed for planting and converted into a tourist destination. Holdridge's Toad Holdridge's Toad The Holdridge's Toad Costa Rica is an endangered species on the 2008 IUCN Red List, announced on October 6. Despite multiple surveys, the amphibian has not been recorded in its rainforest habitat since 1986. Researchers believe the toads may be victims of a devastating fungal disease that has been linked to widespread declines in amphibian species around the world. Cuban Crocodile Population decline of more than 80 percent over the past three generations resulted in the Cuban Crocodile being moved from "Endangered" to "Critically Endangered" on the 2008 Red List. Hunting, interbreeding with other crocodile species and declining habitat quality have contributed to the decline of the small, freshwater crocodile, which is found only in Cuba. Edit this paragraph Mathematician among animals
Make a square with three sides in a golden rectangle (a rectangle with a width-to-length ratio of 0.618), and the remaining part is another golden rectangle. It can be made into a square again in turn. By connecting the centers of these squares in order, a "golden spiral" can be obtained. Oceanographers have discovered that "golden spirals" have been found on nautiluses, horny bodies of some animals, or molluscs with shells. Scientists also discovered that coral polyps can remember the "calendar" wonderfully on their bodies; they carve 365 rings on their body walls every year, that is, they "draw" one ring a day. What's even stranger is that paleontologists also It was found that coral polyps 350 million years ago "painted" 400 rings per year. Why is this? Astronomers tell us that at that time, the earth rotated for only 21.9 hours in a day, and the year was not 365 days, but 400 days. It can be seen that coral polyps can "calculate" and "record" the time of a year based on changes in celestial phenomena, and the results are very accurate. Ants are also excellent "mathematicians".
British scientist Hunston once 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. He found that in ants Forty minutes after those three pieces of food, there were only 28 ants gathered in the smallest piece of grasshopper, but there were 44 in the second piece, and 89 in the third piece. The latter group was almost twice as many as the former group. Bees can be regarded as "genius mathematical calculations and designers". The hives built by worker bees are quite amazing. The obtuse angles of the rhombus at the bottom of the honeycomb it builds are all 109°28′, and all the acute angles are equal to 20°32′. After theoretical calculations by mathematicians, it is at this angle that the largest rhombus can be made with the least amount of material. Red-crowned cranes always migrate in groups and line up in the shape of the characters "人" and "一". The angle of the "herringbone" shape is always 110°. Half of the angle of the "herringbone" shape is exactly 54°44′8″, but the angle of the diamond crystal is also exactly this degree.
Edit this paragraph The function of animal tails
We all know that the tail of the kangaroo is very developed, thick and long, so the tail of the bear rat is longer, and it is longer than the tail of the kangaroo. Its body is even longer. What is the purpose of their tails? In the Australian grassland, the kangaroo is an animal with poor self-defense ability. It must always be on guard against invading enemies and run away whenever there is an enemy. In order to observe the enemy's situation, it must stand. At this time, the tail plays a role in supporting the body. The long tail of the bear rat also has its magical uses. When a bear rat jumps to a high place, it must exert enough strength on its waist, hind legs and tail before it can jump. When crossing wires, it also uses its tail to maintain balance, just like an acrobat holding a long pole when walking a tightrope. The squirrel's tail plays a greater role. Squirrels often jump up and down from trees. This big tail can increase the squirrel's jumping distance. When a squirrel jumps from one tree to another, it straightens its tail and can jump more than ten meters. Relying on this ability, when the squirrel encounters a ferocious animal, it can escape quickly. In addition, when a squirrel jumps down from a tree, its big tail acts like a parachute, allowing the squirrel to land safely on the ground. When it falls to the ground, its big tail is fluffy, thick and soft, and acts as a sponge cushion. When the squirrel rests at night, it puts its big tail on its body and covers its head and body like a quilt to keep warm. The tail of a bird is used to control direction, just like the rudder on a ship. You can see this if you look closely at the tail of an eagle as it hovers in the sky. The swallow's tail is scissor-shaped and is used to change direction suddenly.
Edit this paragraph to remove items
Animals
The defensive behavior of animals is to deal with external aggression, defend their own survival, or to warn other individuals in their own group. behavior that occurs.
Food storage behavior
Fundamentally speaking, animals ingest food in order to absorb the nutrients that make up the body - various organic and inorganic substances, and to carry out various physiological activities. of energy. This is the feeding behavior of animals. Therefore, when food is abundant, some animals will store some food and eat it again when they are hungry. This behavior is called hoarding behavior.
Aggression
Animal aggression refers to attacks or fights between individuals of the same species. In the animal kingdom, animals of the same species often attack or fight each other due to competition for food, mates, nest areas, and territories.
Reproductive behavior
The reproductive behavior of animals is rich and colorful. It includes a wide range of contents, mainly including the identification of male and female animals, occupying breeding space, courtship, mating, incubation, Child care, etc.
Animal thinking