Unravelling the life cycle of ‘&amp;lt;i&amp;gt;Polystomella crispa&amp;lt;/i&amp;gt;’: the roles of Lister, Jepps and Myers

John W Murray

doi:10.1144/0262-821x11-034

Abstract

Abstract. The meticulous observations of Lister, Jepps and Myers involved the culturing of material, monitoring the behaviour of live individuals over periods of days and weeks and at different times of the year, and decalcifying tests in order to stain and examine the protoplasmic contents with the best available microscopes. They all based their studies at the Laboratory of the Marine Biological Association in Plymouth and Myers and Jepps overlapped in the early 1940s although they chose to work separately. Through their combined efforts they determined that the life cycle of Elphidium crispum (Linné) (formerly called Polystomella crispa) involves an alternation of generations, sexual and asexual, over a two-year period. This has remained the ‘classic’ life cycle of benthic foraminifera, although subsequent studies, including those of Myers, have revealed other patterns. Lister also established that test dimorphism is not related to sex but to the asexual and sexual phases of reproduction.

Highlights

IntroductIon The life cycle of fewer than 30 species of foraminifera were known by 1999 (Goldstein, 1999) and no further studies have been published since that date
In the nineteenth century the younger Joseph Jackson Lister was the major British zoologist investigating the biology of benthic foraminifera
Because of poor health he was advised to take long cruises and to give up medicine. On these cruises he developed an interest in foraminifera and this led to a lectureship in Zoology at Cambridge (Vickerman & Sleigh, 2000)

Summary

Introduction

IntroductIon The life cycle of fewer than 30 species of foraminifera were known by 1999 (Goldstein, 1999) and no further studies have been published since that date. The American zoologist Earl Hamlet Myers (1898–1975) studied the life history of Polystomella crispa at the same time as Jepps.

Results

Conclusion