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The interspecific trade‐off between growth versus mortality rates of tree species is thought to be driven by functional biology and to contribute to species ecological niche differentiation. Yet, functional trait variation is often not strongly correlated with growth and mortality, and few studies have investigated the relationships of both traits and niches, specifically encompassing above and belowground resources, to the trade‐off itself. These relationships are particularly relevant for seedlings, which must often survive resource limitation to reach larger size classes.We investigated the functional basis of the interspecific growth–mortality trade‐off and its relationship with ecological niches for seedlings of 14 tree species in a tropical forest in southwest China.We found evidence for an interspecific growth–mortality trade‐off at the seedling stage using 15 functional traits and 15 ecological niche variables. None of the organ‐level traits correlated with growth, mortality, nor the trade‐off, whereas specific stem length (SSL), a biomass allocation trait, was the only trait to have a significant correlation (positive). Moreover, light‐defined niches were not correlated with growth, mortality or the trade‐off, but soil‐defined niches did. Species at the faster growth/higher mortality end of the trade‐off were associated with higher fertility defined by lower soil bulk density and slope, and higher soil organic matter concentration and soil total nitrogen.Our findings indicate the importance of stem elongation and soil fertility for growth, mortality and their trade‐off at the seedling stage in this Asian tropical forest. Our findings contrast with analogous studies in neotropical forests showing the importance of photosynthesis‐related leaf traits related to insolation. Therefore, the functional drivers of demographic rates and trade‐offs, as well as their consequences for ecological niches, can vary among forests, likely owing to differences in biogeography, canopy disturbance rates, topography and soil properties. Moreover, the effects of functional trait variation on demographic rates and trade‐offs may be better revealed when biomass allocation is accounted for in a whole‐plant context. Read the freePlain Language Summaryfor this article on the Journal blog.
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This content will become publicly available on September 1, 2026
Different Aspects of Dominance Are Not Equivalent When Testing for Trade‐Offs in Ant Communities
ABSTRACT Differences in dominance are frequently invoked to explain the outcomes of competition. Yet, what it means to be dominant, and which traits underlie dominance, are poorly understood. Here, we sought to determine the relationships between multiple aspects of dominance, the potential for trade‐offs with discovery ability, and the traits associated with these patterns within a high elevation community of five ant taxa. We examined several common dominance metrics—behavioral dominance (winning aggressive encounters at both the individual and colony levels), numerical dominance (abundance and activity in baits and pitfall traps), and ecological dominance (high relative frequency in baits)—and found that individual‐ and colony‐level behavioral dominance was positively correlated, as were ecological and numerical dominance. However, colony‐level behavioral and numerical dominance were negatively correlated, and no other dominance metrics were associated. There was a dominance‐discovery trade‐off, as increased behavioral (but not numerical or ecological) dominance was associated with slower resource discovery. This trade‐off was likely driven by behaviorally dominant ants having larger body sizes and recruiting a greater biomass of workers to baits. In contrast, fast discoverers were more abundant in the environment (i.e., numerically dominant). Complementing our empirical study, a meta‐analysis of 54 responses from 21 studies showed that the association between dominance and discovery ability depended on the dominance metric. Whereas discovery ability was positively correlated with numerical dominance, its relationships with behavioral and ecological dominance were highly variable and not significantly different from zero. Overall, our empirical findings, in combination with the synthesis of past studies, demonstrate that different aspects of ant dominance are not equivalent. Yet, regardless of dominance type, there is little evidence that dominance‐discovery trade‐offs occur in most ant communities.
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- PAR ID:
- 10686880
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 15
- Issue:
- 9
- ISSN:
- 2045-7758
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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