Japanese bantam

A young Black-tailed buff Japanese bantam cockerel, which has not yet developed the breed's characteristic large tail and comb

The Japanese bantam has very short legs.[7]^:142 This trait is caused by a single lethal gene. All proper Japanese bantams are then heterozygous meaning that when the birds are bred, 25% of the embryos will receive two mutant alleles and die in shell. The other 50% of the embryos will receive one mutant allele and one wild type allele and will then be short-legged. The remaining 25% receive two wild type alleles and have legs that are longer than what most breeders want. Long-legged birds bred to each other will never produce short-leg offspring.

There are many colour varieties of Japanese bantam, with standardised colours including birchen grey, black, black mottled, black-tailed buff, black-tailed white, blue, blue mottled, blue-red, brown-red, buff Columbian, cuckoo, dark grey, golden duckwing, gray, lavender, Miller's gray, partridge, red, red mottled, silver-grey, tri-coloured, wheaten and white.[5] There are also frizzle-feathered[3] and Silkie-feathered variations.[8] These chickens have been known to live for up to 13 years with proper care.