In rural areas folklore often claimed this condition was not just peculiar to cattle, but extended also to human twins this belief perpetuated for generations, as was mentioned in the writings of Cuthbert Bede. Both teams are now credited with the discovery. Lillie, who published it in Science in 1916. The discovery was made independently by American biologist Frank R.

The result was published in 1916 by Tandler and Keller. Several researchers made the discovery that a freemartin results when a female fetus has its chorion fuse in the uterus with that of a male twin. It was hypothesized early in the 20th century that masculinizing factors travel from the male twin to the female twin through the vascular connections of the placenta because of the vascular fusion and affect the internal anatomy of the female. The 18th-century physician John Hunter discovered that a freemartin always has a male twin. Freemartins are known to have been described by the Roman writer Varro, who called them 'taura'.

Freemartin brave new world