list of figures - Terry Sunderland

4.5 ANT / RATTAN ASSOCIATIONS
It has been long reported that ants and rattans share, what is speculated to be a
mutually beneficial relationship (Bequaert, 1922; Ridley, 1910; Corner, 1966;
Whitmore, 1990; Dransfield, 1979; Tomlinson, 1990; Dransfield and Manokaran,
1994; Tuley, 1995). However, few studies have attempted to determine the nature of
the relationship, nor take stock of whether there really is a mutual benefit to having
ants colonise many rattan taxa.
There are numerous recorded examples where ants and plants have formed close,
often mutually beneficial, relationships (Janzen, 1966; 1969; 1972; Bentley, 1976;
1977; Lock, 1986; Huxley, 1986). Such relationships are often quite distinct from
other forms of plant/animal interaction. Whilst other organisms may consume,
pollinate or disperse plants, ants are often, although not always, conspicuously absent
from these activities. Despite this, it has been argued that ants are the organism most
commonly found to play an integral role in the interaction between the plant and its
immediate environment (Huxley, 1986).
It has been postulated that ants and plants have a relationship based mainly on defence
(Huxley, 1986) and any rattan collector, be they botanical or commercial, can vouch
for the ferocious defence that ants provide to protect their rattan hosts. In addition to
this defence role, some evidence suggests that ants might also play a role in the
provision of nutrients to the host (Rickson, 1979; Rickson and Rickson, 1986). In
studies of Daemonorops verticillaris and D. macrophylla in Asia, Rickson and
Rickson (1986) found that the nutrients from accumulated plant debris, were absorbed
by the ant nest material (which itself is comprised of a combination of spines and
plant hairs). A further adaptation which has been identified on rattan palms, is the
presence of scale insects (Coccus spp.) on the sheath that appear to be “farmed”, by
the ants (Dransfield, 1979; Whitmore, 1990). The excretions of the sweet honeydew
of the scale insects is used to nourish the developing ant pupae and both the scale
insects and plant host are then protected vigorously by the ant colony. In Africa, this
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Although some fragments of the seed coat of Eremospatha macrocarpa were encountered in nest
traps (Whitney et al., 1998).
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