Nature's Megadiversity in Mexico

Where I live, Churintzio, Michoacan  a semi-rural small town in the western central highlands of  Mexico, is not known as being a “hot spot” for its biological wealth. Yet, in the fall and winter when I go birding  for a couple of hours or so, over diverse terrain I may see more than fifty species of birds. During the rainy season,  walking the “Cemetery Pond Trail” while covering about a kilometer, I may see upwards of 80 species of insects usually including multiple types of  caterpillars, butterflies, dragonflies,  wasps, moths, flies, grasshoppers, centipedes, bees, ants,  bugs, and a plethora of beetles; also on those walks I am likely to see a variety of spiders, toads, frogs, turtles, lizards, and perhaps  a snake, venomous or not. At other times on the same or different easily accessible local trails, I might see rabbits, squirrels, opossums, deer, foxes, coyotes, various rodents, and quite rarely, maybe a bobcat; unseen by me so far are two other mammalian inhabitants of the hills of Churintzio, raccoons and mountain lions. Moreover, in terms of flora depending on where I am hiking, I will see a variety of cacti, agave, trees, shrubs, and in the rainy season up to a dozen and a half of different kinds of wildflowers. Closer to home, really in our home, at the beginning of the rainy season scorpions will inevitably appear. Consequently, as I have (mostly) delightfully discovered, Churintzio is an ecological microcosm of Mexico as a whole.

You see, Mexico which represents only approximately 1.5% of the earth’s land area, out of 170 countries ranks 5th in the world in species diversity as it is home to about 10% of the planet’s biodiversity. Moreover, as identified by Conservation International, Mexico is one of only seventeen countries to have been determined to be “megadiverse.” These seventeen countries which, in addition to Mexico, are comprised of Australia, Brazil, China, Colombia, the Democratic Republic of the Congo, Ecuador, India, Indonesia, Madagascar, Malaysia, Papua New Guinea, Peru, the Philippines, South Africa, the U.S.A, and Venezuela, constitute about 70% of the world’s biological wealth.

Worldwide, Mexico ranks first in reptiles (11%), second in mammals (12%), fourth in amphibians (7%), and 10th in birds (11%). Percentage-wise the country has 14% of the world’s crustaceans, 8% of its mollusks, 8% of its butterflies, 8% of its bees/wasps/ants, and 7% of its spiders. Mexico also ranks fourth in vascular plants; it is first in pines, cacti (45%), and agave (75%). Interestingly, Mexico has an extremely high rate of endemism as, overall, about half of the country’s species can only be found in Mexico.

Although the stereotype that the country has a lot of cactus is quite accurate, it is not accurate to say that the entire, or even most of the country is arid. If that were the case, then Mexico would not have such a richness of species. Rather, due to an enormous amount of environmental variants, it is a megadiverse land primarily as a result of latitudinal span (bridging tropical and temperate zones), relatively recent climate history, and complex topographic diversity. Mexico is one of the few countries whose topography ranges from arid deserts, dry scrublands, temperate forests, high altitude alpine areas, subtropical forests, tropical forests, and extensive coral reefs.

In an attempt to ensure the long-term viability of its diverse species, the country has taken several steps to do so. Approximately 2500 species (at least on paper!) are protected by Mexican law. Covering 170,000 square kilometers, within the borders of Mexico are 159 “Protected National Areas”: there are 24 biosphere reserves; 64 national parks; 4 national monuments; 26 areas of protected flora and fauna; 4 natural resource protection areas, and 17 species rich diversity sanctuaries. For example, in the state of Quintana Roo on the Yucatan Peninsula, Sian Ka’an Biosphere Reserve, a UNESCO World Heritage Site, whose territory includes about 10% of the state’s total land mass, covers approximately 1.3 million acres and is a real ecological "hot spot" as it is home to 103 known mammal species including 5 species of cat-jaguar, puma, ocelot, margay, and jaguarondi- 336 species of bird, 42 species of amphibians and reptiles, 52 species of fish, around 1200 plant species, is the nesting ground for numerous species of wading birds, and is a vital nesting site for two endangered species of sea turtles.

However, the threats to Mexico’s vast array of species megadiversity are also mega. Sad to say, they are mostly a result of “human nature.” These environmental threats include natural habitat loss and degradation, forest fragmentation, fires both natural and manmade, pollution, unsustainable and illegal land/resource use, (often illegal) collection and trade of plants and wildlife, global climate change, and strains placed on the environment due to rural poverty.

While what I have ‘discovered” in Churintzio species-wise may very well be a microcosm of Mexico’s miraculous and wonderous mega diversity, unfortunately what I have witnessed in terms of a high percentage of that town’s residents attitudes and actions towards nature may also be a microcosm of the nation, both rural and urban, as a whole. If I were asked to describe that mentality, I would say that oh too many people indifferently disregard and disrespect the environment. Over the course of the few years that I have lived there, repeatedly I have seen legally and illegally habitat destroyed that consequently posed a threat to numerous species, especially birds. Be it the dumping of basura/garbage haphazardly in ravines or in waterways or along trails, the cutting down of trees for fences or for tillable land, cutting down for no apparent reason swaths of shrubs and bushes, or deliberately running over with their vehicles such animals as frogs, turtles, and snakes, or the killing of birds by slingshot by youth “just for fun,“ these actions have had a negative impact on many species of life forms.

Indeed, it is fantastic that Mexico is a country that has such an abundance of and diversity of flora and fauna. Yet, despite the numerous species protection laws and protected areas, it is not so fantastic that many people self-servingly and intergenerationally put those species at-risk. The preservation of nature and “human nature” should not and need not be mutually exclusive constructs either in theory, law, or better yet, actualization.