[10] Charles Darwin read Sir John's 1809 pamphlet, and was impressed with a passage that elaborated on how "the weak and the unhealthy do not live to propagate their infirmities".

[12] Darwin's seminal work On the Origin of Species, first published in 1859, cited Sir John's experiments in pigeon breeding,[14] and recalled "That most skilful breeder, Sir John Sebright, used to say, with respect to pigeons, that 'he would produce any given feather in three years, but it would take him six years to obtain head and beak.

[12] Although the exact makeup of the breed is uncertain, it is thought that he created the gold Sebright by cross-breeding a buff Nankin bantam hen, a small gold-spangled Hamburgh-like hen and a small hen-feathered Pit Game cock; he later created the silver Sebright by crossing his golds with a white Rosecomb cock bought from the new Zoological Gardens of the Zoological Society of London, established in 1826.

As a true bantam, all Sebrights are very small in stature; males weigh an average of 22 ounces (620 grams) and females 20 oz (570 g).

Cocks carry a rose comb covered with fine points, and a small spike that sweeps back from the head (called a leader).

[21] Some breeders consider hen feathering to have an adverse effect on the fertility of male Sebrights, and may use cocks that don't carry the trait for breeding purposes, despite their automatic disqualification in shows.

Due to the unique characteristic hen feathering, molecular biologists have found the Sebright bantam a useful model organism in the study of sex hormones.