''Nesoryzomys darwini'', also known as Darwin's nesoryzomys or Darwin's Galápagos mouse, is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

species of

rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...

in the genus ''

Nesoryzomys ''Nesoryzomys'' is a genus of rodent in the tribe Oryzomyini of family Cricetidae, endemic to the Galápagos Islands. Five species have been described, with two of them considered extinct. Other rodents restricted to the Galápagos include '' Me ...

.''

Distribution and habitat

''N. darwini'' was

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

Santa Cruz Island Santa Cruz Island (Spanish language, Spanish: ''Isla Santa Cruz'', Chumashan languages, Chumash: ''Limuw'') is located off the southwestern coast of Ventura, California, United States. It is the largest island in California and largest of the ei ...

in the

Galápagos Islands The Galápagos Islands () are an archipelago of volcanic islands in the Eastern Pacific, located around the equator, west of the mainland of South America. They form the Galápagos Province of the Republic of Ecuador, with a population of sli ...

. It was probably

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

and inhabited burrows or rock crevices under bushes.

Extinction

Only four specimens exist, collected by Frank Wonder between 12 and 16 January 1929. This extinction may have been caused by

competition Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indi ...

from (and disease spread by) the introduction of invasive

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing and painting, brown is usually made by combining the colors Orange (colour), orange and black. In the ...

and

black rat The black rat (''Rattus rattus''), also known as the roof rat, ship rat, or house rat, is a common long-tailed rodent of the stereotypical rat genus ''Rattus'', in the subfamily Murinae. It likely originated in the Indian subcontinent, but is n ...

s. The other ''Nesoryzomys'' known from Santa Cruz, ''

Nesoryzomys indefessus ''Nesoryzomys indefessus'', also known as the Santa Cruz nesoryzomys or Indefatigable Galápagos mouse, is an extinct species of rodent from the genus ''Nesoryzomys'' of family Cricetidae from Galápagos Islands of Ecuador. It formerly lived on Sa ...

'', is also extinct; other species of the genus survive on different islands.Dowler, R.C., Carroll, D.S. and Edwards, C.W. 2000. Rediscovery of rodents (Genus ''Nesoryzomys'') considered extinct in the Galápagos Islands. Oryx 34(2):109–118. ISSN 0030-6053

References

Endemic fauna of the Galápagos Islands Extinct rodents Mammals of Ecuador Rodent extinctions since 1500 Nesoryzomys Extinct mammals of South America Mammals described in 2008 Species made extinct by human activities {{Sigmodontinae-stub