Rosa Susan Penelope Beddington FRS[1][4] (23 March 1956 – 18 May 2001) was a British biologist[3] whose career had a major impact on developmental biology.

[5][19] Beddington taught at the newly established Cold Spring Harbor Laboratories summer course on manipulating the mouse embryo from 1986, including two years as co-organiser with Robertson.

A talented artist, she designed the Waddington Medal, awarded for outstanding performance and contribution to the field of developmental biology.

She has established using her great skills in micromanipulation, many of the key features of gastrulation in the mouse, a fundamental process in mammalian development.

This work provides the first evidence that axial pattern in mammalian development originates in extra-embryonic tissue and that anterior identity is established before the formation of the primitive streak.