Algunos aspectos de la evolución de la vegetación de México

Various factors have influenced the characteristics of vegetation over Mexico such as: geographical position, orography, volcanism, emersions and immersions, climatic fluctuations during the Tertiary, glaciations as well as various migrations that have taken place at various times in various directions. Another aspect that has contributed to the diversity in flora and vegetation in Mexico is the development of an endemic element in flora and even in vegetation. This is important specially to xerophitic and temperate forest. All of this results in a complex phytogeographic analysis of flora due to the co-existence, in some communities, of plants with various origins, ages and evolutive histories.