The student of biological science in his final years as an undergraduate
and his first years as a graduate is expected to gain some familiarity
with current research at the frontiers of his discipline. New research
work is published in a perplexing diversity of publications and is
inevitably concerned with the minutiae of the subject. The sheer number
of research journals and papers also causes confusion and difficulties
of assimilation. Review articles usually presuppose a background know-
ledge of the field and are inevitably rather restricted in scope. There
is thus a need for short but authoritative introductions to those areas
of modern biological research which are either not dealt with in
standard introductory textbooks or are not dealt with in sufficient
detail to enable the student to go on from them to read scholarly
reviews with profit. This series of books is designed to satisfy this
need. The authors have been asked to produce a brief outline of their
subject assuming that their readers will have read and remembered much
of a standard introductory textbook on biology. This outline then sets
out to provide by building on this basis, the conceptual framework
within which modern research work is progressing and aims to give the
reader an indication of the problems, both conceptual and practical,
which must be overcome if progress is to be maintained.