PATTERNS OF DIVERSIFICATION IN PHYTOPHAGOUS INSECTS

Chapter 2: The Phylogenetic Dimension of Insect-Plant Interactions:
A Review of Recent Evidence
The dramatic expansion of research on insect/plant interactions prompted by
Ehrlich and Raven’s (1964) essay on coevolution focused at first mainly on the proximate
mechanisms of those interactions, especially the role of plant secondary chemistry, and
their ecological consequences. Subsequently, in parallel with the resurgence of
phylogenetics beginning in the 1970s and 80s, there arose increasing interest in the long-
term evolutionary process envisioned by Ehrlich and Raven (e.g., Benson et al. 1975,
Zwölfer 1978, Berenbaum 1983, Mitter and Brooks 1983, Miller 1987). Since the early
1990s, spurred in part by the increasing accessibility of molecular systematics, there has
been a happy profusion of phylogenetic studies of interacting insect and plant lineages.
The results so far have reinforced skepticism about the ubiquity of the particular macro-
evolutionary scenario envisioned by Ehrlich and Raven, now commonly termed “escape
and radiation” coevolution (Thompson 1988). However, this model continues to inspire
and organize research on the evolution of insect/plant assemblages because it embodies
several themes of Neo-Darwinism, each of interest in its own right, which have been
taken up anew in the modern re-embrace of evolutionary history. In this chapter we
attempt to catalog some of the postulates about phylogenetic history derivable from
Ehrlich and Raven’s essay, and evaluate their utility for explaining the structure of
contemporary insect/plant interactions.
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