The study of chimeras began by accident in 1825 when a French nurseryman named Adam inadvertently created a graft chimera between Cystisus purpurea and Laburnum anagyroides.

The original graft between these plants failed and a shoot growing from the graft union produced a plant with flowering traits of the purple Cytisus and the yellow Laburnum.

The plant was sold as a novelty, but caught the eye of biologists as a possible "graft hybrid".

Photo of the yellow and purple flowers of +Laburnocytisus adamii.

+Laburnocytisus adamii produces purple and yellow flowers on the same plant!

Charles Darwin incorrectly felt that +Laburnocytisus adamii was a graft hybrid that represented the vegetative fusion of cells. Hans Winkler in 1907 reinvestigated this phenomenon by grafting black nightshade (Solanum nigrum) onto tomato (Lycopersicon esculentum).

He then cut the plant at the graft union. The resulting shoots had characteristics of both graft partners.

He concluded that this was because part of the meristem had cell layers from the two partners producing a chimera (see the chimera section for more information).

Illustration showing nightshade being grafted to tomato, and how the meristem then grows from the grafting point with cell layers from both plants.

Winkler coined the term chimera to describe this plant.

Two years later Erwin Baur noted that variegated plants naturally displayed a phenotype similar to a graft chimera.

This was the start of the study of chimeras that has done so much for understanding the organization of the shoot meristem.

Photo of the 'Freak of Nature' geranium.

He worked with a geranium called 'Freak of Nature'.