ENDEMIC SPECIES: CHARACTERISTICS AND EXAMPLES IN MEXICO - BIOLOGY - 2025

An endemic species is one that is only found in a specific geographic region. A species can be endemic to an entire continent or only to a relatively small area; such as a mountain range in a certain elevation zone, a lake, or an island.

Endemic species are often confined to a certain area because they are highly adapted to a particular niche. They may eat only a certain type of plant that is found nowhere else, or a plant may be perfectly adapted to thrive in a very particular climate and soil type.

Ajolote, endemic species of Mexico

Due to specialization and inability to move to new habitats, some endemic species are frequently at risk of extinction. It occurs if, for example, a new disease affects the population, the quality of its habitat is threatened, or an invasive species enters its niche and becomes a predator or a competitor.

Endemism is more common in some regions than others. In isolated settings - such as the Hawaiian Islands, Australia and the southern tip of Africa - many of the natural species are endemic. In less isolated regions, such as Europe and much of North America, the percentage of endemic species can be much lower.

Main features

Tied to their environment

Species is the smallest taxonomic classification, each species is closely adapted to its own environment. Therefore, the species are often endemic to small areas and local environmental conditions.

The genus, a broader class, is usually endemic in larger regions. Families and orders tend to have an even larger distribution, often at the level of the continents.

Vulnerable

Because endemic animals and plants, by definition, have limited geographic ranges, they can be especially vulnerable to human encroachment and habitat destruction.

Island species are especially vulnerable because islands commonly lack large predators, and many endemic islands evolved without defenses against predation. Cats, dogs and other carnivores introduced by sailors have decimated many endemic species on the islands.

Hawaii's flora and fauna, exceptionally rich before the Polynesians arrived with pigs, rats, and agriculture, were severely depleted because their range was limited and they had nowhere to take refuge as human settlement progressed.

Rainforests, with extraordinary species diversity and high rates of endemism, are also vulnerable to human encroachment. Many of the species that are killed on a daily basis in the Amazon rainforests are locally endemic, so their full range can be removed in a short time.

Main types of endemism

Indigenous

Most often, endemism is considered at the lowest taxonomic levels of genus and species.

Animals and plants can become endemic in two general ways. Some evolve in a particular place, adapt to the local environment, and continue to live within the limits of that environment. This type of endemism is known as "autochthonous" or native to the place where they are found.

Allochthonous

In contrast, an "alien" endemic species is one that originated elsewhere but has lost most of its former geographic range.

A well-known example of allochthonous endemism is the California Coast Redwood (Sequoia sempervirens), which spread across North America and Eurasia millions of years ago, but today exists only in isolated patches near the northern coast of California.

Why are endemisms important?

Endemic species are important for a number of reasons:

1- Since endemic species have a generally limited distribution, threats to these species carry a greater risk of extinction than species that are widely distributed.

2- According to the book Climate Change and Biodiversity, edited by Thomas E. Lovejoy and Lee Hannah, when an endemic plant species becomes extinct it takes between 10 and 30 endemic animal species.

3- By definition, endemic species are highly adapted to their area of ​​distribution. As the conditions of their environment change, whether due to anthropogenic or natural causes, their adaptations can function as competitive strengths or weaknesses.

In other words, some endemic species from different regions can function as a kind of "collective insurance" for continued genetic diversity in the face of rapid changes, while others are at the greatest risk of extinction as conditions change.

Therefore, endemic species are an important group for the conservation of biological diversity.

Examples of endemic species in Mexico

Amole de Guerrero (

The Agave vilmoriniana plant, popularly known as Guerrero amole, is a species of agave endemic to Mexico. This plant is recognized by the shapes of its twisted leaves.

Naturally, this agave prefers the cliffs of the southern ravines of Sonora, Chihuahua, Sinaloa, Jalisco, Durango, Nayarit, and Aguascalientes, typically between elevations of 600 to 1,700 meters.

Vilmorinian agave

The Agave vilmoriniana has one of the highest concentrations of sapogenin; in some parts of Mexico the leaves are cut, dried and the fibers beaten into a brush with incorporated soap.

The octopus agave, the name by which it is also known, is grown as an ornamental plant to plant in gardens and containers.

Palma de Guadalupe (

The Brahea edulis species is an endemic palm to the island of Guadalupe, although it has also been reported to have been planted elsewhere. It is a fan palm that can reach 13 meters in height.

Brahea edulis

They are distributed between 400 and 1000 meters above sea level and the entire native population consists of old trees with little success during the last 150 years or so.

Until recently, Guadalupe Island had a large population of goats. The presence of these goats prevented the regrowth of native trees and, as a consequence, the ecosystem was drastically altered.

Guadalupe cypress (

The Guadalupe cypress is a species of cypress endemic to Mexico. It is found only on Guadalupe Island, in the Pacific Ocean west of Baja California.

Cupressus guadalupensis is found at altitudes between 800 and 1280 meters in the chaparral habitats and recovering forests of the island.

It is an evergreen coniferous tree, with adult trees that reach 10 to 20 meters in height.

The foliage grows in dense sprays, dark green to grayish green. The leaves are scale-shaped, 2 to 5 mm long, and are produced on rounded shoots.

Mexican axolotl (

Axolotls are amphibians that spend their entire lives under water. They exist in nature in one place: the complex of a network of artificial channels, small lakes and temporary wetlands that help supply water to the 18 million residents of Mexico City.

Ambystoma mexicanum

Axolotls are unusual among amphibians in that they reach adulthood without undergoing metamorphosis. Instead of developing lungs and continuing their life on land, the adults retain their gills and remain in the water.

Since 2010, wild axolotls have been in danger of extinction due to urbanization in the city and the consequent contamination of the water, as well as the introduction of invasive species such as tilapia and perch.

Cuitlacoche from Cozumel

The Mexican wolf is a subspecies of gray wolf that was once native to southeastern Arizona, western Texas, and northern Mexico.

It is the smallest of the gray wolves in North America and its ancestors were probably the first gray wolves to enter this territory after the extinction of the Beringia wolf.

Canis lupus baileyi

Since the mid-20th century, it has been the most threatened gray wolf in North America, through a combination of hunting, trapping, and poisoning.

Flat-headed bat (

This endemic bat from Mexico is one of the smallest in the world. It grows to a length of between 51 and 76mm, and weighs approximately 7g. The ears are furred and the face is devoid of ornamentation.

It is a difficult creature to detect; in fact, it was thought to be extinct in 1996 until new sightings were recorded in 2004.

Its distribution is restricted to a small area in the states of Coahuila, Nuevo León and Zacatecas in the Sierra Madre Oriental mountain range, in the northeast of the country. It has specific habitat requirements, so it is confined to montane forests with Yucca and Pinion Pine.

References

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