According to DigoPaul, the alternation is the act and the result of switching. This verb, which comes from the Latin word alternāre, has several meanings, generally linked to the variation or distribution of something.
For example: “The alternation between slow themes and other moving ones makes the album have different climates”, “We cannot allow indefinite reelection: without alternation in power, democracy does not exist”, “The coach announced that he will not choose a single captain, but will opt for alternation so that several players can wear the tape “.
The idea of alternation appears in the field of biology with reference to the succession of asexual and sexual generations when plant or animal species reproduce. In sexual reproduction, the alternation of the nuclear phases occurs. Meiosis results in a haploid phase, while gametes then fuse to form the diploid phase.
The crop rotation, on the other hand, refers to the practice of various growing plants in the same space through a series of cycles. In this way, the soil is not depleted. Furthermore, since plants have different needs and characteristics, diseases or pests do not continue.
In the field of politics, there is talk of alternation to refer to the change of government. If the same political party governs for several consecutive electoral periods, or because there are no direct elections, the alternation does not exist: power is always held by the same sector. On the other hand, if the Conservative Party governs four years, then the Liberal Party for four years and later the Conservative Party returns, the alternation of power occurs.
Precisely a perfect example of political alternation of this type is found in Spain. In this country, in the late nineteenth and early twentieth centuries, a bipartisan system was established with alternation in the government of the Restoration. The two parties that were “taking turns” at the head of the country were the Liberal Party, which had Práxedes Mateo Sagasta as its leader, and the Conservative Party, whose main person in charge was Antonio Cánovas del Castillo from Malaga.
This stage, which was inspired by the existing model in the United Kingdom, put an end to the existing political pluralism and was also called turnismo. During this process, who was in charge of deciding which party should be in charge of the country was the king, Alfonso XII. And it did so taking into account the attrition that the political group in question or the needs of the people might have at that time.
It is considered that with this measure of taking turns in power, to a certain extent, riots and all kinds of pronouncements came to a halt.
In this process, an important role is also played by what was called the El Pardo Pact. It seems that it was an agreement that Sagasta and Cánovas reached at the moment in which the imminent death of the monarch was expected. In order to avoid an instability situation when this died, they certified the need to reach consensus between both formations in favor of the country. That is to say, to establish a turn of parties.