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

While cockroaches are known to produce a variety of
acoustic stimuli in several functional contexts (Roth and
Hartman, 1967), a recent review of vibrational communication
included no examples of Blattaria (Virant-
Doberlet and Cokl, 2004). It is known, however, that Periplaneta
americana is capable of detecting substrate-borne
vibration via receptors in the subgenual organ of the tibiae
(Shaw, 1994b), and that male cockroaches use a variety
of airborne and substrate-borne vibratory signals
when courting females, including striking the abdomen
on the substrate. Tropical cockroaches that perch on
leaves during their active period may be able to detect
predators or communicate with conspecifics via the substrate
(Chapter 6). Adults and nymphs of Cryptocercus
transmit alarm to family members via oscillatory movements
nearly identical to those of termites (Cleveland et
al., 1934; Seelinger and Seelinger, 1983).
Trail Following
In termites, trail following mediates recruitment and is a
basic component of foraging behavior. In several species,
the source of the trail pheromone is the sternal gland
(Stuart, 1961, 1969; Peppuy et al., 2001). Cockroaches
that aggregate are similar to eusocial insects in that there
is a rhythmical dispersal of groups from, and return to, a
fixed point in space (e.g., Seelinger, 1984), suggesting that
cockroaches have navigational powers that allow them to
either (1) resume a previously established membership in
a group or (2) find their harborage. It is difficult to separate
the two, and site constancy and homing ability may
be a general characteristic of cockroaches regardless of
their social patterns (Gautier and Deleporte, 1986). Periplaneta
americana and B. germanica follow paths established
by conspecifics as well as trails of fecal extracts (Bell
et al., 1973; Kitamura et al., 1974; Miller and Koehler,
2000). Brousse-Gaury (1976) suggested that adult P.
americana use the sternal gland to deposit a chemical trail
during forays from the harborage. When the antennae of
P. americana were crossed and glued into place, the cockroaches
consistently turned in the opposite direction of a
pheromonal trail in t-mazes, indicating that the mechanism
employed is a comparison between the two antennae
(Bell et al., 1973). There are indications of this kind
of chemo-orientation in other species as well. The myrmecophile
Attaphila fungicola follows foraging trails of its
host ant (Moser, 1964), and female cockroaches that have
recently buried oothecae may disturb the substrate in an
attempt to obliterate odor trails from detection by cannibals
(Rau, 1943).
Kin Recognition
Kin recognition is well developed in those cockroach
species in which it has been sought. Juveniles of B. germanica
are preferentially attracted to the odor of their
own population or strain (Rivault and Cloarec, 1998).
Paratemnopteryx couloniana females recognize their sisters
(Gorton, 1979), first instars of Byrsotria fumigata recognize
and orient to their own mother (Liechti and Bell,
1975), and juveniles of Rhyparobia maderae prefer to aggregate
with siblings over non-siblings, a tendency most
pronounced in first instars (Evans and Breed, 1984).
Nymphs of Salganea taiwanensis up to the fifth instar are
capable of distinguishing their parents from conspecific
pairs (T. Matsumoto and Y. Obata, pers. comm. to CAN).
Like termites (reviewed by Vauchot et al., 1998), nonvolatile
pheromones in the cuticular hydrocarbons can
and do transfer among individuals via physical contact in
cockroach aggregations (Roth and Willis, 1952a; Everaerts
et al., 1997; discussed in Chapter 3).
Home Improvement: Digging, Burrowing,
and Building
Among the social insects, termites are noted for the diversity
and complexity of their nest architecture. Both
fecal deposits and exogenous materials (soil, wood)
transported by the mandibles are used as construction
material, and the structure is made cohesive with a
mortar of saliva and fecal fluid. Intricate systems of
temperature regulation and ventilation are typically incorporated,
resulting in a protected, climate-controlled
environment for these vulnerable insects (Noirot and
Darlington, 2000). Cockroaches exhibit rudimentary forms
of these complex construction behaviors, providing support
for the notion that termite construction skills are derivations
of abilities already present in their blattarian ancestors
(Rau, 1941, 1943).
A number of cockroach species tunnel in soil, leaf litter,
guano, debris, rotten, and sometimes sound, wood
(Chapters 2 and 3). Cockroaches also possess the morphological
and behavioral requisites for more subtle
excavation of substrates, as evidenced in oviparous
cockroaches during the deposition and concealment of
oothecae (Fig. 7.2) (McKittrick et al. 1961; McKittrick,
1964). On particulate substrates such as sand female Blattidae
use a raking headstroke to dig a hole, but they gnaw
crevices in more solid substances like wood. Blattellidae
bite out mouthfuls of material on all substrate types. Legs
may be used to help dig holes and to move debris away
from the work site. Euzosteria sordida digs a hole using
backstrokes of the head, followed by movement of each
leg in turn to move sand away from the excavation site
(Mackerras, 1965b). After the hole is the appropriate
depth, the female has a “molding phase,” during which
she lines the bottom of the hole with a sticky layer of substrate
particles mixed with saliva. The ootheca is then de-
TERMITES AS SOCIAL COCKROACHES 153