Cockroache; Ecology, behavior & history - W.J. Bell

NINE
Termites as Social Cockroaches
Our ancestors were descended in early Cretaceous times from certain kind-hearted
old cockroaches.
—W.M. Wheeler, “The Termitodoxa, of Biology
and Society” (in the voice of a termite king)
It has long been known that termites (Isoptera), cockroaches (Blattaria), and mantids
(Mantodea) are closely related (Wheeler, 1904; Walker, 1922; Marks and Lawson, 1962);
they are commonly grouped as suborders of the order Dictyoptera (Kristensen, 1991).
Although there is a general agreement on the monophyly of the order, during the past
two decades the sister group relationships of these three taxa and the position of woodfeeding
cockroaches in the family Cryptocercidae in relation to termites have been lively
points of debate (see Nalepa and Bandi, 2000; Deitz et al., 2003; Lo, 2003 for further discussion).
A variety of factors contribute to obscuring the relationships. First, fossil and
molecular evidence indicate that these taxa radiated within a short span of time (Lo et
al. 2000; Nalepa and Bandi, 2000). A rapid proliferation and divergence of the early forms
would obscure branching events via short internal branches separating clades, instability
of branching order, and low bootstrap values of the corresponding nodes (Philippe
and Adoutte, 1996; Moore and Willmer, 1997). Second, heterochrony played a major role
in the genesis and subsequent evolution of the termite lineage (Nalepa and Bandi, 2000).
It is notoriously difficult to determine the phylogenetic relationships of organisms with
a large number of paedomorphic characters (Kluge, 1985; Rieppel, 1990, 1993). Reductions
and losses make for few morphological characters on which to base cladistic analysis,
and parallel losses of characters by developmental truncation make it difficult to distinguish
between paedomorphic and plesiomorphic traits (discussed in Chapter 2).
Third, cockroaches in the particularly contentious family Cryptocercidae live and die
within logs and have left no fossil record. Fourth, extant lineages of Dictyoptera represent
the terminal branches of a once luxuriant tree, with many extinct taxa. Finally, several
phylogenetic studies of the Dictyoptera have been problematic because of ambiguous
character polarity, inadequate taxon sampling, and questionable reliability of the
characters used for phylogenetic inference (for discussion, see Lo et al. 2000; Deitz et al.,
2003; Klass and Meier, 2006).
The bulk of current evidence supports the classic view (Cleveland et al., 1934; Grassé
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