The evolution of insect swarms from XNUMX million years ago

Chapter 6 Evolution of Feeding Structure

after a while. During the perception, the genetic sequence of the short-winged horseshoe crab was extracted from the mother nest. Now, another brand new species can be produced by the mother nest.

But maybe it's because the horseshoe crab and the horseshoe crab both belong to the species Platypodius. Lin Yi was surprised to find that those special synaptic structure gene fragments related to the nervous system can be integrated into the gene sequence of the horseshoe crab, and the output can be A short-winged horseshoe crab that is directly controlled by his consciousness.

However, the original short-winged horseshoe crab, as a scavenger that scavenged for garbage on the seabed, was of little use to Lin Yi for the time being. It required the gene editing capabilities of the mother nest to modify its genetic sequence.

Concentrating his consciousness, he read the gene sequence of the horseshoe crab and first embedded the fragments in the genome of the Sakaban soft-shell turtle that determine the development of myelin to strengthen its nervous system.

Then, looking at the pair of tiny pincer-like claws next to the mouth of the short-winged horseshoe crab, Lin Yi fell into deep thought.

Platypod horseshoe crabs and later spider scorpions belong to the subphylum Chelicipoda under the phylum Arthropods. As the name suggests, regardless of their size, they all have one thing in common. They have a pair of small pincers called chelicerae next to their mouths. Assist with eating.

Of course, there are other functions as well. For example, pteropods horseshoe crabs use their chelicerae as killing weapons, and later generations of spiders use their chelicerae as fangs for injecting venom.

The feather-winged horseshoe crab also has this structure, but it is not developed. In the same proportion, it is even worse than the short-winged horseshoe crab that picks up garbage and eats it. However, Lin Yi does not intend to equip the feather-winged horseshoe crab with an enlarged version of the short-winged horseshoe crab. Instead, he planned to find another way.

I mentally selected the gene fragment related to the first pair of limbs of Brachyphyllus brachyphyllalis excluding the chelicerae, and then copied the gene fragment that determines the terminal development of the chelicerae and replaced its position in the gene sequence.

After slightly adjusting the gene segment that determines limb size, a short-winged horseshoe crab genetic template with two pairs of chelicerae, one large and one small, appeared in the genetic sequence storage of the mother's nest.

In the idea, in addition to the pair of chelicerae near the mouth that are used to assist oneself in eating, the second pair of more developed pincer-like limbs can also tear food, assist the surrounding individual to eat under the network of consciousness, and make up for the poor eating ability of individual feather-winged horseshoe crabs. Shortcomings.

Thinking about it, I edited the size of the short-winged horseshoe crab gene template again - since there was a feather-winged horseshoe crab genetic template as a reference, it was not difficult to enlarge the size of the short-winged horseshoe crab. In the end, its size reached half of the feather-winged horseshoe crab. This is Lin Yi guessed the most suitable size.

The first such individual Brachypteryx began to be cultivated in the second mother's nest.

With the current size of the second brood, it is just right to produce individuals of this size. Not long after, a large individual short-winged horseshoe crab waved an extra pair of pincers, swam out from the hole on the surface of the mother's nest, and slowly landed on the surface of the cornerstone's corpse.

Immediately, under Lin Yi's control, a pair of slender claws began to operate, and began to tear pieces of flesh from the corner stone's torn and unrecognizable surface for absorption by himself and the mother's nest.

The modified short-winged horseshoe crab with a pair of large claws and a pair of small claws is indeed much more efficient at tearing flesh and blood than the feather-winged horseshoe crab with only a pair of small claws. But compared with Lin Yi's expected efficiency, it is still not enough.

With a thought, he once again edited the gene sequence of the short-winged horseshoe crab through the mother nest, and selected the gene fragments of another pair of limbs.

Lin Yi's idea was quite simple and crude. If one pair of large pincers was not enough, he would grow another pair. Two pairs of four large pincers would tear flesh and blood. Their efficiency could not reach the level of being usable.

But imagining the new improved individual shape of the short-winged horseshoe crab, Lin Yi suddenly thought of a serious problem. Horseshoe crab has four pairs of eight appendages in total. The first gene editing has modified one pair of limbs into chelicerae, leaving only six for walking.

If we continue to modify the second pair of limbs into chelicerae, we will face a problem that has troubled the chelicerae subphylum for 400 million years, and there is no good solution.

In the evolution of early chelicerates, a large number of appendages were specialized into page-like structures for breathing - book gills. Later generations of arachnids wrapped it into their bodies and became book lungs. Such a structure gives them the strongest breathing ability in the entire arthropod phylum, but it also brings about a problem - the remaining appendages are not enough.

The most primitive arthropods, such as trilobites, like today's centipedes and millipedes, had one or two pairs of appendages per body segment.

In arthropods with a higher degree of evolution, most of the complex structures outside the body, such as mouthparts, antennae, and even reproductive organs, are specialized from redundant appendages.

Therefore, the most evolved insects among arthropods retain only six appendages, while the remaining less evolved insects retain more.

Because the chelicerate subphylum specialized too many appendages into gills in the early stage, in the subsequent evolution, there were not enough legs, which became a permanent pain for them.

Just like today, if the short-winged horseshoe crab is equipped with a pair of chelicerae again, the remaining two pairs of legs will be difficult to support the movement of the individual. And if you want to conjure a pair of appendages out of thin air, you can't do it with current gene editing capabilities.

This made Lin Yi couldn't help but sigh - in his previous life, he had often laughed at the dilemma of chelicerates racking their brains and frantically demolishing the east wall to make up for the west wall in order to meet the needs of eating, hunting, sensing, walking or swimming, and reproduction at the same time. Thinking that now, it was his turn to experience such a dilemma.

Suddenly, a gene fragment came into Lin Yi's field of vision - it was a trilobite gene fragment that he had completely dismissed before.

As the most primitive arthropod, trilobites have unspecialized appendages, with one pair on each body segment.

If the gene fragment that determines the number of appendages in trilobites is embedded into the gene sequence of horseshoe crab, this problem that has plagued the chelicerate subphylum for hundreds of millions of years can be perfectly solved. Thinking about it, he immediately started taking action.

This time the gene editing involves the overall body structure, the changes are relatively large, and some time is wasted.

Eventually, a gene segment in the abdomen, the first segment of the hindbody, that determines the development of ventral gills was replaced by a pair of gene segments from the trilobite gene sequence that determines the growth of primitive appendages.

Later, the gene fragments related to appendage morphology were replaced with fragments from the paddle-shaped paddling feet of the horseshoe crab, successfully giving the short-winged horseshoe crab an additional pair of paddling feet similar to the feather-winged horseshoe crab.

Now, the latest improved horseshoe crab template has two pairs of large claws, two pairs of walking legs and a pair of paddling legs. Lin Yi immediately controlled the second brood to start producing such short-winged horseshoe crab templates, and asked them to use two pairs of developed chelicerae that were added later and a pair of small chelicerae that originally grew near the mouth to tear the soft tissue of the corner stone with all their strength. , supplying the consumption of the second brood.

This time, the improved individual feeding efficiency of the short-winged horseshoe crab finally met Lin Yi's requirements, allowing him to continue planning the next step with peace of mind.

(End of this chapter)