Friends who are familiar with me know that there is a cat called Huang Jie in my family, today Huang Jie broke the vase when she went shopping in the living room, and she was busy cleaning up for half a day to get it done, and then looked back, Huang Jie was sitting on the side watching the liveliness. In a fit of rage, I snorted at her and blasted her away. Although I am very angry, I have to say that the cat's body movements are really quite pleasing to the eye, and it is very graceful when walking on tiptoes, and it is full of explosive power when running.
I don't know if you noticed that when cats and dogs walk, they are actually just toes on the ground, and the heels are raised.
I think it is necessary to talk about the topic of our article today, the way and types of terrestrial mammals walk. You know, terrestrial mammals are a very large family, with a wide variety and characteristics, they have a lot in common, and they have a lot of differences.
In terms of walking type, terrestrial mammals can be divided into three types: plantar, toe and hoofed.
Before we get started, we'll familiarize ourselves with the skeletal foot structure of terrestrial mammals.
Take our human feet as an example, human foot bones can be roughly divided into three parts: the phalange bone (the bone in the toe), the metatarsal bone (the bone of the foot surface and the sole force) and the tarsal bone (the bone in the heel and ankle), and the tarsal bone can be divided into the tagrade bone, the foot scaphoke bone, the dice bone, the wedge bone and the calcaneus bone, and then the tibia, which does not belong to the category of foot bones.
The palm of the hand corresponds to the bone, metacarpal bone, and wrist bone (you can see where it is by name). The same is true for animals that walk on all fours, with the forefoot bones being phalanges, metacarpals, and carpal bones, and the hindfoot bones being phalanges, metatarsals, and tarsal bones.
The most profound things are not to be said, everyone simply understand these terms and the corresponding positions, you can have a concept of the three types of walking we will talk about next.
First, let's talk about the type of walking that is plantar. The pronunciation of metatarsal is "straight", the same as the pinyin of the toe, but the pronunciation is different, the former is two sounds, the latter is three sounds.
The way of walking is that the phalanges, metatarsals and tarsal bones all land on the ground, representing species such as primates, urs, marsupials, etc. We humans are also plantar animals, we can look down, when the foot is on the ground, from the toes to the heel are flat on the ground, when walking forward, we will first lift the heel, when we land, the heel will touch the ground first, and then the whole foot will be flat on the ground again.
This is how plantar animals walk, and at this point rats, bears, monkeys, orangutans, kangaroos and other animals are just like us. However, most animals walk on all fours, and the same is true when the forelimbs are on the ground, with all the phalanges and metacarpal bones landing on the ground, and the carpal bones partially landing on the ground.
The most mainstream theory in the academic community is that mammals were first plantar, and later the diversity of species increased, and the environment in which everyone lived was different, so they evolved in different directions, and gradually appeared toe-toe and hoofed animals to adapt to their respective living environments.
The advantage of plantar travel is that it can provide more stable support for the animal itself, and at the same time it is more resistant to weight. And on the basis of the hind limbs, some planters have gradually differentiated into forelimbs that can perform flexible movements, which is why many plantar animals can stand upright (such as rats, bears, kangaroos, raccoons, etc.), and some plantar animals have evolved a strong function of the forelimbs, which are today's primates, including humans.
However, the disadvantages of metatarsal travel are also obvious, because the phalanges, metatarsals and tarsal bones all fall on the ground, so the speed and flexibility of the animals will be greatly reduced, not as good as the toe and hoofed animals.
Although the speed of the kangaroo is very fast, it is not strictly speaking running, but relies on its developed hind limbs and tail muscles to make continuous jumps, and the kangaroo cannot be faster if it moves forward step by step.
Unlike metatarsals, the toe walks only by the phalange, and the metatarsals and tarsals of toe walkers are lifted, and the metatarsals and metatarsals do not come into contact with the ground unless lying on the ground or squatting on the ground.
The representatives of toe-walking animals are felines, canines, hyenas, etc., which are basically more ferocious predators, relying on speed or strength to sneak and chase prey.
There are cats or dogs in the house shovelers can observe their hind legs, usually standing or walking, running, cats and dogs on the back foot is bent backwards, the calf protruding backwards of the bone joint, is actually the tarsal bone, equivalent to our human heel, and the tarsal bone is close to the ground vertical length of this piece is the metatarsal bone, equivalent to the human foot, but they usually walk when this piece is not on the ground, only the bones of the toes land, so it is called toe walking animals.
There's a term called creeping, which describes how sneaky, tiptoeing people look, generally in order to make smaller noises and move more sensitively.
In fact, the state of "creeping hands and crept feet" is that humans are simulating the walking style of toe animals, which is also the main feature of toe walking.
Not only that, but toeed walking animals liberated the long metatarsals and the tarsal bone that acted as a bearing, and the front of the phalanges evolved sharp or strong toenails that allowed them to run more explosively and more effectively to grip the ground, improving the efficiency of hunting.
Other toeed walkers evolved thick foot pads and claw sheaths that allowed their claws to retract freely to play sneaking and ambushing, and they are today's cats (with the exception of cheetahs).
If toe-toed walking animals specialize in explosive power and the ability to run fast in a short period of time, then hoofed walking animals specialize in long endurance and better running speed.
In terms of bones, the way of walking in the hoof line is more special, and even the toe bones no longer touch the ground, but "toenails" on the ground.
To meet this need, the toenails of ungulates gradually became stronger and thicker along the evolutionary path, which is what we call hooves. The representative species of ungulates are deer, sheep, horses, antelopes, etc., although they do not have an advantage in short-term explosive power, they have superior endurance than toe-walking animals, and their running speed is often better.
You can take a closer look at the hind legs of the zebra in the picture below, the backward protruding bone segment is the tarsal bone (like the toe walking animal), the hoof is the specialized toenail, and the hoof is a small section that gradually becomes thinner, then the thickened joint, and then the long "calf" is the lower leg, this calf is the metatarsal bone, and the thinner section above the hoof is a highly healed toe bone.
However, it should be noted that not all animals with hooves are ungulates, and some herbivores that do not pursue running speed also have wide toenails, but they do not only walk on the ground on their toenails, these animals have short toebones, sometimes flat on the ground, or only raise a slight angle.
The way this type of animal walks can be called "half-hoof line" or "half-toed line", which means that the animals are pigs, hippos, elephants, capybaras and so on.
These animals are either thick-skinned, or fat, or have long fangs for self-defense, or are very good at swimming, do not need to run at extreme speed, and have a rounded body, only the tip of the hoof will be very inconvenient to walk, and can not fully bear the weight, so the toe bone will also play a certain role in support.