The Red List Index (RLI), based on the IUCN Red List of Threatened Species, is an indicator of the changing state of global biodiversity. The IUCN Red List of Threatened Species (also known as the IUCN Red List or Red Data List) created in 1963 is the world's most comprehensive inventory of the global Biodiversity is the variation of Life forms within a given Ecosystem, Biome or for the entire Earth. It defines the conservation status of major species groups, and measures trends in extinction risk over time. The conservation status of a Species is an indicator of the likelihood of that species remaining extant either in the present day or the near future In Biology, a species is one of the basic units of Biological classification and a Taxonomic rank. In Biology and Ecology, extinction is the cessation of existence of a Species or group of taxa. By conducting conservation assessments at regular intervals, changes in the threat status of species in a taxonomic group can be used to monitor trends in extinction risk. Taxonomy is the practice and science of classification The word comes from the Greek, taxis (meaning 'order' 'arrangement' and, nomos RLIs have been calculated for birds and amphibians, using changes in threat status for species in each of the groups. Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Prehistoric amphibian Amphibians (class Amphibia such as Frogs Toads Salamanders Newts Gymnophiona, Sirens and
As well as taxonomic groups, RLIs can show trends in extinction risk according to biogeographic realm, habitat type, and dominant threat process. Biogeography is the study of the distribution of Biodiversity over Space and Time. A habitat (which is Latin for "it inhabits" is an Ecological or environmental area that is inhabited by a particular Species.
Producing indices of change in extinction risk by comprehensively assessing whole species groups, while feasible for well studied groups with relatively few species, is not suitable for all taxonomic groups. Assessing every species in the larger and lesser known groups which comprise the majority of the world’s biodiversity, such as insects and plants, is not practical. Insects ( Class Insecta) are a major group of Arthropods and the most diverse group of Animals on the Earth with over a million described Plants are living Organisms belonging to the kingdom Plantae.
The Red List Index (sampled approach) (SRLI) has been developed in order to determine the threat status and trends of lesser-known and less charismatic species groups. It is a collaboration between IUCN members and is coordinated through the Institute of Zoology (IoZ), the research division of the Zoological Society of London (ZSL). The Institute of Zoology (IoZ is the research division of the Zoological Society of London (ZSL in England. The Zoological Society of London (sometimes known by the abbreviation ZSL) is a Learned society founded in London in April 1826 by Sir Thomas Stamford The SRLI is based on a representative sample of species selected from taxonomic groups within vertebrates, invertebrates, plants, and fungi. Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes An invertebrate is an Animal lacking a Vertebral column. The group includes 98% of all animal Species — all animals except those in the Chordate Plants are living Organisms belonging to the kingdom Plantae. A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ
Assessment of the selected species will provide baseline information on the current status of biodiversity. Reassessment at regular intervals will identify changes in threat status over time to provide a more broadly representative picture of biodiversity change.
The aim is that the SRLI will aid in the production of a global biodiversity indicator capable of measuring whether the rate of biodiversity loss has been reduced. In addition, it will help to develop a better understanding of which taxonomic groups, realms or ecosystems are deteriorating the most rapidly, why species are threatened, where they are threatened, what conservation actions exist and which actions are needed. An ecosystem is a natural unit consisting of all plants animals and micro-organisms( Biotic factors in an area functioning together with all of the non-living physical ( The aim is to provide policy makers, resource managers, scientists, educators, conservation practitioners and the general public with more thorough knowledge of biodiversity change and further tools with which to make informed decisions.
In April 2002 at the Convention on Biological Diversity (CBD), 188 Nations committed themselves to actions to: “… achieve, by 2010, a significant reduction of the current rate of biodiversity loss at the global, regional and national levels…” The RLI has been adopted by the CBD as one of the indicators to measure progress towards this important target, and specifically to monitor changes in threat status of species. April 2002: January - February - March - April - May - June - July - August - September The Convention on Biological Diversity, known informally as the Biodiversity Convention, is an international Treaty that was adopted in Rio de Janeiro in June 1992 For the film see 2010 The Year We Make Contact. For the book see 2010 Odyssey Two.
Butchart, S. H. M. , Akçakaya, H. R. , Chanson, J. , Baillie, J. E. M. , Collen, B. , Quader, S. , Turner, W. R. , Amin, R. , Stuart, S. N. , Hilton-Taylor, C. 2007. Improvements to the Red List Index. PLoS ONE 2(1): e140. 
Butchart, S. H. M. , Stattersfield, A. J. , Baillie, J. , Bennun, L. A. , Stuart, S. N. , Akçakaya, H. R. , Hilton-Taylor, C. , Mace, G. M. 2005. Using Red List Indices to measure progress towards the 2010 target and beyond. Philosophical Transactions of the Royal Society B. 360: 255-268. 
Butchart, S. H. M. , Stattersfield, A. J. , Bennun, L. A. , Shutes, S. M. , Akçakaya, H. R. , Baillie, J. E. M. , Stuart, S. N. , Hilton-Taylor, C. , Mace, G. M. 2004. Measuring Global Trends in the Status of Biodiversity: Red List Indices for Birds. PLoS Biology. 2 (12): e383. 
Nic Lughadha, E. , Baillie, J. , Barthlott, W. , Brummitt, N. A. , Cheek, M. R. , Farjon, A. , Govaerts, R. , Hardwick, K. A. , Hilton-Taylor, C. , Meagher, T. R. , Moat, J. , Mutke, J. , Paton, A. J. , Pleasants, L. J. , Savolainen, V. , Schatz, G. E. , Smith, P. , Turner, I. , Wyse-Jackson, P. , Crane, P. R. 2005. Measuring the fate of plant diversity: towards a foundation for future monitoring and opportunities for urgent action. Philosophical Transactions of the Royal Society B. 360: 359-372. 
Stuart, S. N. , Chanson, J. S. , Cox, N. A. , Young, B. E. , Rodrigues, A. S. L. , Fischman, D. L. , Waller, R. W. 2004. Status and Trends of Amphibian Declines and Extinctions Worldwide. Science. 306: 1783-1786.