INVESTIGADORES
FRACCHIA sebastian
artículos
Título:
Are subordinate ants the best seed dispersers? Linking dominance hierarchies and seed dispersal ability in myrmecochory interactions
Autor/es:
ARANDA-RICKERT; FRACCHIA SEBASTIAN
Revista:
ARTHROPOD-PLANT INTERACTIONS
Editorial:
SPRINGER
Referencias:
Lugar: Berlin; Año: 2012 vol. 6 p. 297 - 306
ISSN:
1872-8855
Resumen:
Abstract True myrmecochory involves the dispersal of
elaiosome-bearing seeds by ants. Between the guild of ants
that are attracted to these seeds, only a few of them will act
as effective dispersers, that is, transporting the seeds to
suitable sites (the nests) for germination and plant establishment.
Ant communities are known to be highly hierarchical,
and subordinate ants quickly deliver resources to
their nest rather than consuming it on-site, thereby avoiding
encounters with more dominant species. As a result of a
series of studies that were carried out during summer in
semi-arid Northwest Argentina, we have found that the
most important seed disperser of the myrmecochorous
plant Jatropha excisa Griseb. (Euphorbiaceae), the ant
Pogonomyrmex cunicularius pencosensis Forel, was the
most subordinate species during interspecific interactions.
The daily timing of release of the J. excisa seeds through
ballistic dispersal increased their probability of being
removed by the highly thermophilic P. cunicularius pencosensis.
Foraging during the warmest hours of the day
allowed P. cunicularius pencosensis ants to avoid the risk
of interference competition with dominant species, which
also behaved as elaiosome predators. As a conclusion,
subordinance behaviour appears to be integral to successful
myrmecochory, and also the timing of seed release plays a
key role in shaping the dynamics of myrmecochorous
interactions. Therefore, ant-dispersed plants should not
only favour their discovery by subordinate ants, but also
should present their seeds at those times of the day when
the behaviourally dominant ants are less active.