You may have noticed that there are seasons in which certain insects abound more than at other times of the year. Have you wondered why this happens? The availability of resources is a reason, but another even more important is climatic conditions. Animals have developed hair or body structures in which cold or warm summers can withstand. But although insects are more primitive and do not do this, they do have strategies to escape adverse conditions. This is known as Diapause. In this ecology article, we will explain in detail What is the diapause, its types and examples of species that use it.
What is the diapause in insects
The diapause is a strategy in which insects can suspend its development or growth and reach a phase of inactivity for a long timein order to surpass an inconvenient season. This inactivity can occur in any phase of the insect, either during the embryonic, larval, pupal, or adult, depending on the species in question and its genetic determination.
The diapause happens by a Modification in the endocrine systemin which the glands stop secreting the hormones they would normally release. This is regulated by the brain nesting cells that pass to inactivity. In pupae and larvae, this period is controlled by the Ecdysone hormone, and in adults it is regulated by the retention by the Corpora Allata gland, which produces the youth hormone.
The diapause is very useful for warm areas to survive winterand vice versa, where the insects of temperate zones exceed well The warm summer.
This process is typical frequent in insects, but not only happens in this group. Also It can be observed in plants and animals under the name of Dorman.
PHASES OF THE DIAPAUSE
The series of processes that are activated before the arrival of adverse conditions can be divided into the following chronological phases:
- Induction: In order for the diapause to activate the insect organism, the changes that announce a close severe change in the environment will perceive by stimuli. For example, they can capture the change in the duration of sunlight that announces the arrival of winter. They do not respond immediately to adverse conditions, but anticipate the indications prior to them in order to prepare in advance.
- Preparation: Insects begin to supply reserve material that will serve them during the inactivity phase. They accumulate lipids, carbohydrates, proteins, and other indispensable molecules. In some cases this phase may be absent.
- Initiation: After the preliminary stages, the organism stops physiologically. There may be changes in color, in the production of enzymes or changes in behavior.
- Maintenance: The development is stopped and the sensitivity to external factors decreases to prevent the diapause from ending.
- Termination: After a stimulus, or after a certain time, the diapause gradually reaches its end. This happens a little before the unfavorable conditions end.
- Quiescence: Since the diapause does not end together with severe conditions, this state of quiescence and rest works as a transition. His metabolism is not as slow as previously. It is more a lethargy that the insect can awaken when the conditions are optimal to resume your normal life.
Types of diapause
We can find different types of diapause according to certain criteria.
According to the relationship with the environment
- Obliged Diapause: The environment does not play any role, and occurs in some stage of the insect cycle.
- Optional Diapause: In this case it is activated by adverse environmental conditions.
According to the stadium
- Development delay: Present in the egg.
- YEMA ACCUMULATION: In the egg.
- No food from the organism: in the larva and in the adult.
- Stadium extension: In the egg, pupa and larva.
- Delay in reproduction: In the adult.
- Staticity or lack of movement: In the adult, larva or pupa.
Difference between diapause and quiescence
Although quiescence is part of the diapause, both are different processes.
- Quiet is a lethargy process Where the insect is not completely inactivewhile the diapause is stricter in the sense that there is physiologically a careful forced by environmental conditions.
- Quiet can be finished at will For the animal, but the diapause does not.
Diapause examples
Finally, we indicate some diapause examples:
- Mosquito Diapause: We know very well that the long -awaited summer brings the negative side of the season: to the mosquitoes. If in winter we do not see these insects that bite it is because they are passed through the diapause. In this case, the state of inactivity can occur at any stage and is activated by the modification of sunlight
- Elotero worm diapause Helicoverpa Zea: They enter this phase when they are in a state of pupa, induced by 10 -hour photoperiods.
- Delay of fertilization in mammals: In this case, sperm accumulate to be used later, when environmental conditions are more convenient for the birth of the young.
- Seasonal Mammal Diapause: Embryo can be retained within mother. For example, those who were conceived in autumn and should be born in winter, will do so until spring so that they do not have to go through this raw season.
Now that you know more about what the diapause, its types and examples is, we encourage you to discover which animals hibernate and why.
If you want to read more articles similar to DIAPAUSE: What is, types and exampleswe recommend that you enter our biology category.
- Gilbert, S. (2003) Development biology. Pan -American Medical Editorial.
- Vargas, M. (1998) The mosquito. San José: Editorial of the University of Costa Rica.
