We know that the centipede, which is the first of the five poisons, is generally about 10 centimeters long. Even so, the centipede looks very scary. The largest surviving centipede in the world is the giant Galapagos centipede. It can grow up to 30 cm. But it is only one tenth the size of the giant centipede that appeared in the Carboniferous Period.

In fact, the “giant centipede” that appeared during the Carboniferous period is not what we now call a centipede. It is actually a prehistoric ploidy, called an arthropod. It can only be considered as an ancient relative of centipedes. In fact, it is closer to Ma Lu.

Even if the knotted chest is only an ancient relative of centipedes in the Carboniferous Period, why can it grow up to 3 meters?

carboniferous forests

The reason for this is inseparable from the environment at that time in the Carboniferous Period. During the Carboniferous period, the climate in much of the planet was hot and humid. The warm and humid climate is very conducive to plant growth. The Carboniferous period was a period of great prosperity in the plant world. Plants spread from coastal areas inland, and large areas of fern forest appeared on land.

The flowering of plants has led to a sharp increase in the oxygen content in the air. Scientists have proven that the oxygen content in the air during the Carboniferous period reached 35%. That’s 14 percentage points higher than the current oxygen content.

Animals of the Carboniferous Period

Why does increasing the oxygen content in the air cause the size of arthropods to increase? Terrestrial arthropods, such as centipedes, respire primarily through the organ system. They are based on the ventilation and diffusion of the tracheal system to allow the body tissues to directly absorb oxygen from the air and discharge carbon dioxide. They breathe differently from terrestrial vertebrates. Your breath bypasses the circulatory system. As the oxygen content in the air increases, terrestrial arthropods can obtain more oxygen from the air. This has also caused many arthropods to grow to a large extent.

Changes in Earth’s oxygen content

In addition, the warm and humid climate of the Carboniferous Period, the lush vegetation and other environments are very suitable for insects to survive. Thus, the rich oxygen content coupled with the ideal living environment has ushered in a golden age of development for arthropods. Therefore, the Carboniferous period also has an alias: “age of the giant insect”.

giant dragonfly

Since it is the age of giant insects, it means that many arthropods in the Carboniferous period grew very large. In addition to what we call the “giant centipede”, the knotted chest, there are also giant spiders the size of human heads, with a wingspan of almost 1 meter, giant dragonflies like eagles, and lung scorpions with a body length of 80 centimeters. They are the most representative terrestrial arthropods of the Carboniferous period.

forest fires

Filling the air with high concentrations of oxygen can be a dangerous thing. Because oxygen is an accelerator. During the Carboniferous period, forest fires would occur frequently. The fire ignited the coal seam underground. The fires have been burning for decades or even centuries. The heat, toxic gases, and burning coal caused about 46 percent of species to become extinct at the time. And then there are these giant bugs. This extinction event is known as the Carboniferous coal burning event.

Therefore, the hot and humid climate and the rich oxygen content of the Carboniferous Period not only created the “Giant Worm Age”, but also broke the “Giant Worm Age”.