 The Sind sparrow is a member of the genus Passer , which contains the house sparrow and around twenty other species . In a 1936 review of the house sparrow 's relatives , German ornithologist Wilhelm Meise suggested that the Sind sparrow evolved from an isolated population of house sparrows , noting that the Indus valley is a centre of small bird types . British ornithologist J. Denis Summers @-@ Smith considered the Sind sparrow to be part of the " Palaearctic black @-@ bibbed sparrow " group including the house sparrow , though not one with a particularly close relationship with the house sparrow . Summer @-@ Smith suggested that these species separated 25 @,@ 000 to 15 @,@ 000 years ago , during the last glacial period , when sparrows would have been isolated in ice @-@ free refugia , such as the Indus River Delta , where he thought the Sind sparrow evolved . However , studies of mitochondrial DNA indicate an earlier origin of Passer species , with speciation occurring as early as the late Miocene and early Pliocene , about 5 million years ago . Hume and Ticehurst observed a resemblance , and a possible relation , between the Sind sparrow and the Dead Sea sparrow of the Middle East and Balochistan . William Robert Ogilvie @-@ Grant and Henry Ogg Forbes saw a resemblance to the Abd al @-@ Kuri sparrow , endemic to the island of Abd al @-@ Kuri , in their 1899 description of that species , noted upon by Guy M. Kirwan in a 2008 study . 
