Natural History and Ecosystems

**3**

**Table 1.**

**Chapter 1**

of Mexico

**1. Introduction**

**1.1 Flora, fauna and vegetation**

literature on its protection is analyzed.

**Group Number** 

Vascular plants

**of species worldwide**

*Biodiversity of Mexico according to Mittermeier et al. [2].*

248 428 18000–

**Number of species in Mexico**

30000

Amphibians 4222 284 7 169 60 Reptiles 6458 717 11 368 51 Birds 9040 1050 12 125 12 Mammals 4629 450 10 140 31

**Worldwide/Mexico %**

**Number of endemic species**

15000

7–12 10000–

**Endemic species %**

33–50

*Levente Hufnagel and Ferenc Mics*

Introductory Chapter: Biodiversity

Mesoamerica (starting from the southern states of Mexico) differs from Central America, which is a geopolitical name. The expression "Middle America" is in use as well, which involves all areas south from the border of the US including the Islands of the Caribbean [1]. In this chapter the biodiversity of Mexico is presented and the

Mexico being the largest country in the region is very rich in species in itself (**Tables 1**–**4**). Lot of species occur even in the dry northern areas. In the Chihuahuan Desert 826 plant species are noted by Villarreal-Quintanilla et al. [7], out of which 560 are endemic, 165 are quasi-endemic and és 176 are microendemic. 116 taxa can be originated from a non-arid habitat. The most species-rich are Cactaceae with 141, Asteraceae with 106, Boraginaceae with 34 and Brassicaceae with 31 species. On the California Peninsula 723 endemic species are noted by Riemann and Exequiel [8], claiming that the great number of endemic species is due to the heterogenity of the environment. The flora and fauna are very interesting because the area of Mexico involves the border of *Neotropis* and *Nearctis* (Mexican Transition Zone), which is not exactly a border but rather a wide transition zone, its accurate definition is yet to be created. The determinaion is based on the distribution of the endemic genera characteristic to one or the other area. The several results obtained regarding this vary hugely. The determination of the location and width of the transition zone is different among authors without a consensus, which requires further floristic examinations [9]. Vegetatio varies depending on the topography that has a great role in the fromation of the great number of endemic species as well [10].
