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This content will become publicly available on November 2, 2024

Title: The Causes and Consequences of Seed Dispersal

Seed dispersal, or the movement of diaspores away from the parent location, is a multiscale, multipartner process that depends on the interaction of plant life history with vector movement and the environment. Seed dispersal underpins many important plant ecological and evolutionary processes such as gene flow, population dynamics, range expansion, and diversity. We review exciting new directions that the field of seed dispersal ecology and evolution has taken over the past 40 years. We provide an overview of the ultimate causes of dispersal and the consequences of this important process for plant population and community dynamics. We also discuss several emergent unifying frameworks that are being used to study dispersal and describe how they can be integrated to provide a more mechanistic understanding of dispersal.

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Award ID(s):
2231761 1953934
NSF-PAR ID:
10493734
Author(s) / Creator(s):
;
Publisher / Repository:
Annual Reviews
Date Published:
Journal Name:
Annual Review of Ecology, Evolution, and Systematics
Volume:
54
Issue:
1
ISSN:
1543-592X
Page Range / eLocation ID:
403 to 427
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    McConkey, Kim (Ed.)
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    Abstract Aim

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     Location

    Global.

     Taxon

    The flowering plant families Apocynaceae, Ericaceae, Melastomataceae, Rosaceae and Solanaceae.

     Methods

    We model climatic niche evolution as a variable parameter Ornstein–Uhlenbeck process. However, rather than assuming regimes a priori, we use a hidden Markov model (HMM) to infer the complex evolutionary history associated with different modes of seed dispersal. In addition to allowing for a more accurate picture of the regimes, the use of HMMs allows partitioning the variance of climatic niche evolution to include dynamics independent of our focal character.

     Results

    Lineages dispersed by frugivores tend to have warmer and wetter climatic optima and are generally associated with areas where potential for vegetation growth is higher. However, lineages distributed in more mesic habitats, such as rainforests, are generally associated with slower rates of climatic niche evolution regardless of their mode of seed dispersal.

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    Characteristics of the abiotic environment may facilitate the evolution of some types of plant–animal interactions. Association with frugivores is an important modulator of how plants move in space, but its impact on their climatic niche evolution appears to be indirect. Seed dispersal by frugivores may facilitate the establishment of lineages in closed canopy biomes, but the general slower rates of climatic niche evolution in these habitats are possibly related to other general aspects of the ‘mesic syndrome’ rather than the behaviour of the animals that disperse their seeds.

     
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