Why did European explorations to other areas of the world mark a significant change to collective learning and why did these explorations begin in the mid - to late-fifteenth century?

Because they united all world zones and people worked together.

Explanation:

European exploration took place in the middle of the 15th century and the end of the 15th century because it was at that time that Europeans had the need to look for new trade routes. This era is called the "era of the discoveries", as it allowed for intense marine explorations, carried out mainly by the Spanish and Portuguese, allowing the discovery and creation of commercial relations with Africa, Asia and America, always seeking to enrich the European nations and makes them strong.

These explorations only ended when Europeans managed to map the entire globe, allowing them to unite all areas of the world and people worked together to enrich their countries.