Multi-dimensionality of tree communities structure host-parasitoid networks and their phylogenetic composition

  1. Ming-Qiang Wang
  2. Shi-Kun Guo
  3. Peng-Fei Guo
  4. Juan-Juan Yang
  5. Guo-Ai Chen
  6. Douglas Chesters
  7. Michael Orr
  8. Ze-Qing Niu
  9. Michael Staab
  10. Jing-Ting Chen
  11. Yi Li
  12. Qing-Song Zhou
  13. Felix Fornoff
  14. Xiaoyu Shi
  15. Shan Li
  16. Massimo Martini
  17. Alexandra-Maria Klein
  18. Andreas Schuldt
  19. Xiaojuan Liu
  20. Keping Ma
  21. Helge Bruelheide
  22. Arong Luo
  23. Chao-Dong Zhu

  • Curated by eLife

    eLife logo

    eLife assessment

    The valuable work by authors improves our understanding on the effects of tree diversity on host-parasitoid communities of insects in forests in an experimental setting. Most of the analyses used are solid, but some of the conclusions seem a bit too strong and stretched.

Reviewed by

Read the full article

Listed in

Log in to save this article

Abstract

Environmental factors can influence ecological networks, but these effects are poorly understood in the realm of the phylogeny of host-parasitoid interactions. Especially, we lack a comprehensive understanding of the ways that biotic factors, including plant diversity, tree identity, genetic diversity, overall community composition of higher trophic levels, and abiotic factors such as microclimate, interact to determine host–parasitoid network structure and host–parasitoid community dynamics. To address this, we leveraged a five-year dataset of trap-nesting bees and wasps and their parasitoids collected in a highly-controlled, large-scale subtropical tree biodiversity experiment. We tested for effects of tree species richness, tree phylogenetic and functional diversity, and taxonomic and phylogenetic composition on taxonomic, phylogenetic, and network composition of both host and parasitoid communities. We show that multiple components of tree diversity, tree composition, and canopy cover impacted both, taxonomic and phylogenetic composition of hosts and parasitoids. Generally, top-down control was stronger than bottom-up control via phylogenetic association between hosts and parasitoids, reflecting non-randomly structured interactions between phylogenetic trees of hosts and parasitoids. Further, host-parasitoid network structure was influenced by tree species richness, tree phylogenetic diversity, and canopy cover. Our study indicates that the composition of higher trophic levels and corresponding interaction networks are determined by habitat structure and heterogeneity, which is maintained by trees and especially via phylogenetic links in species-rich ecosystems.

Article activity feed

  1. Version published to 10.7554/elife.100202.1 on eLife
  2. Version published to 10.7554/elife.100202 on eLife
  3. eLife

    eLife assessment

    The valuable work by authors improves our understanding on the effects of tree diversity on host-parasitoid communities of insects in forests in an experimental setting. Most of the analyses used are solid, but some of the conclusions seem a bit too strong and stretched.

  4. eLife

    Reviewer #1 (Public Review):

    Summary:
    The authors analyzed how biotic and abiotic factors impact antagonistic host-parasitoid interaction systems in a large BEF experiment. They found the linkage between the tree community and host-parasitoid community from the perspective of the multi-dimensionality of biodiversity. Their results revealed that the structure of the tree community (habitat) and canopy cover influence host-parasitoid compositions and their interaction pattern. This interaction pattern is also determined by phylogenetic associations among species. This paper provides a nice framework for detecting the determinants of network topological structures.

    Strengths:
    This study was conducted using a five-year sampling in a well-designed BEF experiment. The effects of the multi-dimensional diversity of tree communities have been well explained in a forest ecosystem with an antagonistic host-parasitoid interaction.

    The network analysis has been well conducted. The combination of phylogenetic analysis and network analysis is uncommon among similar studies, especially for studies of trophic cascades. Still, this study has discussed the effect of phylogenetic features on interacting networks in depth.

    Weaknesses:
    (1) The authors should examine species and interaction completeness in this study to confirm that their sampling efforts are sufficient.
    (2) The authors only used Rao's Q to assess the functional diversity of tree communities. However, multiple metrics of functional diversity exist (e.g., functional evenness, functional dispersion, and functional divergence). It is better to check the results from other metrics and confirm whether these results further support the authors' results.
    (3) The authors did not elaborate on which extinction sequence was used in robustness analysis. The authors should consider interaction abundance in calculating robustness. In this case, the author may use another null model for binary networks to get random distributions.
    (4) The causal relationship between host and parasitoid communities is unclear. Normally, it is easy to understand that host community composition (low trophic level) could influence parasitoid community composition (high trophic level). I suggest using the 'correlation' between host and parasitoid communities unless there is strong evidence of causation.

  5. eLife

    Reviewer #2 (Public Review):

    Summary:
    In their manuscript, Multi-dimensionality of tree communities structure host-parasitoid networks and their phylogenetic composition, Wang et al. examine the effects of tree diversity and environmental variables on communities of reed-nesting insects and their parasitoids. Additionally, they look for the correlations in community composition and network properties of the two interacting insect guilds. They use a data set collected in a subtropical tree biodiversity experiment over five years of sampling. The authors find that the tree species, functional, and phylogenetic diversity as well as some of the environmental factors have varying impacts on both host and parasitoid communities. Additionally, the communities of the host and parasitoid showed correlations in their structures. Also, the network metrices of the host-parasitoid network showed patterns against environmental variables.

    Strengths:
    The main strength of the manuscript lies in the massive long-term data set collected on host-parasitoid interactions. The data provides interesting opportunities to advance our knowledge on the effects of environmental diversity (tree diversity) on the network and community structure of insect hosts and their parasitoids in a relatively poorly known system.

    Weaknesses:
    To me, there are no major issues regarding the manuscript, though sometimes I disagree with the interpretation of the results and some of the conclusions might be too far-fetched given the analyses and the results (namely the top-down control in the system). Additionally, the methods section (especially statistics) was lacking some details, but I would not consider it too concerning. Sometimes, the logic of the text could be improved to better support the studied hypotheses throughout the text. Also, the results section cannot be understood as a stand-alone without reading the methods first. The study design and the rationale of the analyses should be described somewhere in the intro or presented with the results.

  6. Version published to 10.1101/2024.06.13.598779v1 on bioRxiv