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Portrait of Axel — Fotopedia
Axel, my axolotl
(c) Armin Hinterwirth
Wikipedia Article

The axolotl ( /ˈæksəlɒtəl/), Ambystoma mexicanum, is a neotenic salamander, closely related to the Tiger Salamander. Larvae of this species fail to undergo metamorphosis, so the adults remain aquatic and gilled. It is also called ajolote (which is also a common name for different types of salamander). The species originates from numerous lakes, such as Lake Xochimilco underlying Mexico City. Axolotls are used extensively in scientific research due to their ability to regenerate limbs.

The conservation status of a group of organisms (for instance, a species) indicates whether the group is still extant (that is, members of it are still alive) and how likely the group is to become extinct in the near future. Many factors are taken into account when assessing conservation status: not simply the number of individuals remaining, but the overall increase or decrease in the population over time, breeding success rates, known threats, and so on.

The IUCN Red List of Threatened Species is the best-known worldwide conservation status listing and ranking system. The system divides threatened species into three categories: Critically Endangered (CR), Endangered (EN), and Vulnerable (VU). Also listed are the documented extinctions that have occurred since AD 1500 and taxa that are extinct in the wild. Lower risk taxa are also divided into categories. The scale of measure has been criticized because, with the lowest rating being "Least Concern", it fails to have a 'nil' measure. Therefore it fails to reflect the scenario where a species is plentiful and thriving.

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) aims to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Critically Endangered is the highest risk category assigned by the IUCN Red List for wild species. Critically Endangered means that a species' numbers have decreased, or will decrease, by 80% within three generations.

As the IUCN does not consider a species extinct until extensive, targeted surveys have been conducted, species which are possibly extinct are still listed as 'Critically Endangered.' A new ideal category for 'Possibly Extinct' has been suggested by BirdLife International to categorize these taxa.

The IUCN Red List of Threatened Species (also known as the IUCN Red List or Red Data List), founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature (IUCN) is the world's main authority on the conservation status of species. A series of Regional Red Lists are produced by countries or organizations, which assess the risk of extinction to species within a political management unit.

The IUCN Red List is set upon precise criteria to evaluate the extinction risk of thousands of species and subspecies. These criteria are relevant to all species and all regions of the world. The aim is to convey the urgency of conservation issues to the public and policy makers, as well as help the international community to try to reduce species extinction.

Major species assessors include BirdLife International, the Institute of Zoology (the research division of the Zoological Society of London), the World Conservation Monitoring Centre, and many Specialist Groups within the IUCN Species Survival Commission (SSC). Collectively, assessments by these organizations and groups account for nearly half the species on the Red List.

The IUCN aims to have the category of every species re-evaluated every five years if possible, or at least every ten years. This is done in a peer reviewed manner through IUCN Species Survival Commission (SSC) Specialist Groups, which are Red List Authorities responsible for a species, group of species or specific geographic area, or in the case of BirdLife International, an entire class (Aves).

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