This led to the domestication of the Syrian hamster. When kept as house pets the Syrian hamster does not hibernate. The book contains the earliest known description of the Syrian hamster. This gene complements a temperature-sensitive mutant isolated from the BHK-21 Syrian hamster cell line. Syrian hamster behavior refers to the ethology of the Syrian hamster ("Mesocricetus auratus"). Syrian hamster breeding is selective breeding on Syrian hamsters. In 1902 Alfred Nehring studied a preserved female Syrian hamster specimen at the Beirut Museum. The Syrian hamster was first recognized as a distinct species in 1839. In 1930 medical researchers captured Syrian hamster breeding stock for animal testing. The Syrian hamster is one of only few exceptions to this activity. The female Syrian hamster has anatomic features that are unique from other animals. There are numerous Syrian hamster variations including long-haired varieties and different colors.