Directed Dispersal: Demographic Analysis of an Ant-Seed Mutualism

@article{Hanzawa1988DirectedDD,
  title={Directed Dispersal: Demographic Analysis of an Ant-Seed Mutualism},
  author={Frances M. Hanzawa and Andrew James Beattie and David C. Culver},
  journal={The American Naturalist},
  year={1988},
  volume={131},
  pages={1 - 13}
}
Certain seed dispersers may benefit plants by depositing seeds in specific microsites favorable for survival or growth. This has been called "directed dispersal." We examine the effects of seed dispersal by ants on the demography of two seed cohorts of Corydalis aurea: one relocated to ant nests by undisturbed ant foragers, and a control cohort of equal numbers planted by hand in the vicinity of each nest. The ant-treated cohort produced 90% more offspring than the control cohort and had a… 
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163 Citations

CRYPTIC CONSEQUENCES OF A DISPERSAL MUTUALISM: SEED BURIAL, ELAIOSOME REMOVAL, AND SEED‐BANK DYNAMICS
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The net effect of seed dispersal by ants on plant populations will depend on how temporal fluctuations in fire regimes influence cost-benefit thresholds related to seed dormancy and seed mortality.
EFFECTS OF DISPERSERS, GAPS, AND PREDATORS ON
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Seedling emergence in this ant-dispersed herb with a relatively long-lived seed bank depends upon a complex of factors, suggesting an interaction of the effects of biotic dispersal to local safe microsites with larger scale effects of spatial and temporal variation in the abiotic environment.
Ant Guild Identity Determines Seed Fate at the Post-Removal Seed Dispersal Stages of a Desert Perennial
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Evaluation of secondary dispersal in a large-seeded tree Aesculus turbinata: a test of directed dispersal
TLDR
The directed dispersal hypothesis for this species is rejected, and it is concluded that the role of rodents in dispersing large seeds secondarily is more important for finding suitable sites merely by enlarging seed shadow and relatively less important for escaping natural enemies.
Effects of Dispersers, Gaps, and Predators on Dormancy and Seedling Emergence in a Tropical Herb
TLDR
Seedling emergence in this ant—dispersed herb with a relatively long—lived seed bank depends upon a complex of factors, suggesting an interaction of the effects of biotic dispersal to local safe microsites with larger scale effects of spatial and temporal variation in the abiotic environment.
Advantages of Seed Dispersal for a Myrmecochorous Temperate Forest Herb
TLDR
Testing how survival of seeds of a myrmecochrous forest herb in two forest sites in southwestern Ohio, USA was affected by the following treatments: distance from parent plant, seed burial, elaiosome removal, and their interactions found that when placed in artificial depots consisting of 10 seeds, only seed burial significantly aided seed survival.
Redispersal of seeds by a keystone ant augments the spread of common wildflowers
Advantages of seed dispersal: A re-evaluation of directed dispersal
TLDR
It is suggested that directed dispersal is more common than previously believed even in the absence of plant adaptations to promote it, and may often be ecologically important if one dispersal vector has a disproportionate effect on plant recruitment.
Testing the directed dispersal hypothesis: are native ant mounds (Formica sp.) favorable microhabitats for an invasive plant?
TLDR
Formica ant mounds are suggested to be favorable microhabitats for E. esula growth following seedling establishment, a likely consequence of nutrient limitation during plant growth.
ANT-MEDIATED SEED DISPERSAL ALTERS PATTERN OF RELATEDNESS IN A POPULATION OF TRILLIUM GRANDIFLORUM
TLDR
This study documents how ant-mediated seed dispersal affects the number and relatedness of seeds in both dispersed and undispersed aggregations and how these patterns influence seedling emergence in the long-lived perennial, Trillium grandiflorum.
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