This is a collection of lists of mammal species by the estimated global population, divided by orders. Lists only exist for some orders; for example, the most diverse order - rodents - is missing. Much of the data in these lists were created by the International Union for Conservation of Nature (IUCN) Global Mammal Assessment Team, which consists of 1700 mammalogists from over 130 countries. They recognize 5488 species in the class.[1][2]
These lists are not comprehensive, as not all mammals have had their numbers estimated. For example, a live specimen of the spade-toothed whale was first observed in December 2010, and the event only recognized as such in November 2012; no estimate yet exists for the global population.[3] The accuracy of the quote numbers may only be an order of magnitude.
It is estimated that the total number of wild mammals in the world is about 130 billion.[4]
