Over millions of years of Earth's formation and development, insects have invaded and existed everywhere. They gradually evolved with their hard shells and bones to protect themselves from predators and environmental threats.
But with weather agents, how do insects keep warm in the winter and cool off in the summer? When they have absolutely no clothes to wear as humans?
Humans are classified as animals (higher order) constant heat, and are also species of warm blooded creatures. The human body controls its constant temperature at 37 degrees Celsius and develops a number of mechanisms to keep or escape heat in case of need. Sweating, goose bumps and shivering are some of the ways our bodies try to keep their internal temperature to the optimal level possible. Other mammals of the constant heat group also evolved different ways to retain heat, such as thick fur (bears) or panting (dogs).
In contrast to thermothermal animals, which are thermoplastic, there is another more common name than cold-blooded animals, including reptiles and amphibians. Their body temperature varies with their ambient temperature level, and this, in addition to some behavioral harms, also has many benefits, especially the higher survival rate than the constant heat species. They do not need to recharge to maintain body temperature. That is why snakes and crocodiles are two "tough" species, regardless of their environment.
So which insect will fall into? Constant heat (hot blood) or variable temperature (cold blood)?
Insects are truly diverse in form, behavior and adaptation.
The answer is both. Although they are unified as "insects" because of their three-legged body and leg characteristics (head, chest and abdomen), in terms of other factors, they are truly diverse in form. , behavior and adaptation. So we have constant heat and heat-changing insects.
We often think of insects as thermoplastic animals. That is true, but not entirely. Basically, some types of bugs can tolerate higher ambient temperatures. The insects are divided into two main types: internal and external .
While thermophilic insects have a mechanism that regulates body temperature according to the surrounding temperature, the internal heat insects keep their internal temperatures at a stable level, especially in certain parts of their body. exposure to the outside environment. The process of selective heating or cooling of certain body parts is called heterothermy. And animals with this ability, such as wasps, moths, butterflies and beetles are often called heterothermic.
Most insects have wings, and for their thin wings to lift their bodies into the air, a lot of energy is required. This requires the insect's body to have a very fast metabolic rate. In particular, at the position of the muscles that control insects' wings, the copper energy reactions generate a lot of heat.
One method of warming up the body in the cold weather of insects is through flights. The wing works hard to speed up blood circulation, helping to spread heat throughout the body. Heat from the chest - the wing position - is transmitted to the lower abdomen, then transmitted into the air via evaporation.
Through flights, insects can heat the body in the middle of a cold weather.
In this way, the abdomen acts as a radiator, where heat is stored when it is cold and the radiator is hot. At the same time, a portion of heat stored during hot weather will be used when the weather changes colder. Insects will be difficult to operate in low temperatures, because the metabolic reactions necessary for the flight will not be fast enough due to this factor.
Usually before flying, they will perform a small warm-up routine, by flapping their wings vigorously back and forth like trembling, to produce a sufficient amount of heat. It is understood that they have to warm up the "engine" for a few minutes before being warm enough to take off.
Especially in insects, flapping wings is not the only way to warm up. Several studies have found a "useless cycle " in honey bees that helps them warm themselves. The futile cycle is a fairly accurate name to describe this process, which is completely useless except accidentally helping insects warm the body.
According to Wikipedia , the futile cycle, also known as the substrate cycle , occurs when two metabolic pathways work in opposite directions simultaneously and have no overall effect other than dissipating the lower energy. thermal form. In insects, it's the glycolysis cycle - breaking down glucose, and making new glucose - creating glucose .
Useless cycles in insects.
Fructose 6 - phosphate (F6P) will be phosphorylated into Fructose 1.6 - phosphate (F1,6P) with catalytic enzyme PFK (phosphofructokinase) during glycolysis. In contrast, Fructose 1,6 - bi phosphate is converted into two molecules during the process of renewing. The first reaction will need energy in the form of ATP, but the opposite will not.
The cells break down ATP to provide energy for the processes, and the ATP production process will also generate a lot of heat. Repeatedly performing the substrate cycle will cause ATP to rapidly deplete without producing any benefits. However, the cells in an insect's body will have to work harder to maintain the supply of ATP, and that - as mentioned above - will produce a sufficient amount of heat to keep them warm.
Usually, both reactions will not be performed simultaneously. Either sugar division, or sugar reconstruction. However, some species of bees have the ability to initiate this cycle on their own to generate heat, and some studies have refuted this conclusion. The debate is still ongoing among researchers on the role of metabolic processes in regulating heat in insects.
To be able to regulate body temperature in accordance with the external environment, insects must first know if the weather is hot or cold. They will "measure and estimate" the outside temperature through a group of receptor cells (receptors) located on the antennae, called the TRP (Trasient Receptor Potential) channels.
Insects won't need to wear warm clothes or sweat because they have their own regulatory mechanisms.
The receptor senses a change in the surrounding temperature, then sends a stream of information signals to their nervous system. The nervous system - through mechanisms that scientists are still exploring - makes the necessary changes on insects' bodies.
Studies have shown that removing some of the receptor cells results in hypothermia (their body temperature drops to normal), while blocking other TRP channels causes them to increase body temperature ( their body temperature rises higher than normal). More interestingly, TRP channels have been conserved during evolution for millions of years, which means that human and insect DNA will have several similar genes responsible for detecting temperature changes. However, insects will not need to wear warm clothes or sweat because they already have the regulatory mechanisms inside the body - and with their very small size.