Pluto's reclassification as a dwarf planet and its shrinkage are separate phenomena. Let's address each of them individually:
Reclassification as a Dwarf Planet: In 2006, the International Astronomical Union (IAU) redefined the definition of a planet. According to the new definition, a planet must meet three criteria: it must orbit the Sun, it must be spherical in shape, and it must have cleared its orbit of other debris. Pluto was found to share its orbit with other small celestial bodies in the Kuiper Belt, so it did not meet the "cleared its orbit" criterion. As a result, it was reclassified as a dwarf planet. This reclassification was based on our evolving understanding of the solar system and the need for a more precise classification system.
Shrinkage: Pluto's shrinkage refers to the geological processes and changes that have occurred on its surface. Data from the New Horizons spacecraft, which conducted a flyby of Pluto in 2015, revealed that Pluto has experienced significant geological activity. This activity includes features such as mountains, valleys, and a thin atmosphere. The exact causes of this activity are not fully understood, but it is believed to be driven by a combination of factors, including heat from the interior, volatile ices, and tidal forces with its largest moon, Charon.
As for the Earth, it is not expected to undergo a similar process of shrinkage and reclassification as a dwarf planet. The reclassification of Pluto was based on specific criteria related to its orbit and the definition of a planet established by the IAU. Earth is much larger and more massive than Pluto, and it has a clear orbit devoid of other massive bodies that could influence its classification. Therefore, Earth is firmly classified as a planet according to the current definition.
It's worth noting that geological processes, including tectonic activity and erosion, continually shape Earth's surface, but these processes are not related to the reclassification of planets.