Developmental Plasticity and Evolution. In: Mary Jane West-Eberhard, Editor, Oxford University Press (2003) Pp. xi+794. Price $50.00 paper.

Phage Therapy: A Renewed Approach to Combat Antibiotic-Resistant Bacteria.

The ecological niche is a key concept for elucidating patterns of species distributions and developing strategies for conserving biodiversity. However, recent times are seeing a widespread debate whether species niches are conserved across space and time (niche conservatism hypothesis). Biological invasions represent a unique opportunity to test this hypothesis in a short time frame at the global scale. We synthesized empirical findings for 434 invasive species from 86 studies to assess whether invasive species conserve their climatic niche between native and introduced ranges. Although the niche conservatism hypothesis was rejected in most studies, highly contrasting conclusions for the same species between and within studies suggest that the dichotomous conclusions of these studies were sensitive to techniques, assessment criteria, or author preferences. We performed a consistent quantitative analysis of the dynamics between native and introduced climatic niches reported by previous studies. Our results show there is very limited niche expansion between native and introduced ranges, and introduced niches occupy a position similar to native niches in the environmental space. These findings support the niche conservatism hypothesis overall. In particular, introduced niches were narrower for terrestrial animals, species introduced more recently, or species with more native occurrences. Niche similarity was lower for aquatic species, species introduced only intentionally or more recently, or species with fewer introduced occurrences. Climatic niche conservatism for invasive species not only increases our confidence in transferring ecological niche models to new ranges but also supports the use of niche models for forecasting species responses to changing climates.

Most invasive species largely conserve their climatic niche.

Biodiversity is defined by trait differences between organisms, and biologists have long sought to predict associations among ecologically important traits. Why do some traits trade off but others are coexpressed? Why might some trait associations hold across levels of organization, from individuals and genotypes to populations and species, whereas others only occur at one level? Understanding such scaling is a core biological problem, bearing on the evolution of ecological strategies as well as forecasting responses to environmental change. Explicitly considering the hierarchy of biodiversity and expectations at each scale (individual change, evolution within and among populations, and species turnover) is necessary as we work toward a predictive framework in evolutionary ecology. Within species, a trait may have an association with another trait because of phenotypic plasticity, genetic correlation, or population-level local adaptation. Plastic responses are often adaptive and yet individuals have a fixed pool of resources; thus, positive and negative trait associations can be generated by immediate environmental needs and energetic demands. Genetic variation and covariation for traits within a population are typically shaped by varying natural selection in space and time. Although genetic correlations are infrequently long-term constraints, they may indicate competing organismal demands. Traits are often quantitatively differentiated among populations (local adaptation), although selection rarely favors qualitatively different strategies until populations become reproductively isolated. Across species, niche specialization to particular habitats or biotic interactions may determine trait correlations, a subset of which are termed "strategic trade-offs" because they are a consequence of adaptive specialization. Across scales, constraints within species often do not apply as new species evolve, and conversely, trait correlations observed across populations or species may not be reflected within populations. I give examples of such scale-dependent trait associations and their causes across taxonomic groups and ecosystems, and in the final section of the paper, I specifically evaluate leaf economics spectrum traits and their associations with plant defense against herbivory. Scale-dependent predictions emerge for understanding plant ecology holistically, and this approach can be fruitfully applied more generally in evolutionary ecology. Adaptive specialization and community context are two of the primary drivers of trade-offs and syndromes across biological scales.

A scale-dependent framework for trade-offs, syndromes, and specialization in organismal biology

https://onlinelibrary.wiley.com/doi/epdf/10.1111/ecog.04772

Ecological memory at millennial time‐scales: the importance of data constraints, species longevity and niche features

How ecological niche breadth evolves is central to adaptation and speciation and has been a topic of perennial interest. Niche breadth evolution research has occurred within environmental, ecological, evolutionary, and biogeographical contexts, and although some generalities have emerged, critical knowledge gaps exist. Performance breadth trade-offs, although long invoked, may not be common determinants of niche breadth evolution or limits. Niche breadth can expand or contract from specialist or generalist lineages, and so specialization need not be an evolutionary dead end. Whether niche breadth determines diversification and distribution breadth and how niche breadth is partitioned among individuals and populations within a species are important but particularly understudied topics. Molecular genetic and phylogenetic techniques have greatly expanded understanding of niche breadth evolution, but field studies of how niche breadth evolves are essential for providing mechanistic details and allowing the de...

/pdf/evolution-of-ecological-niche-breadth-1ky1febg57.pdf

Jorge Montiel

Papers

Evolution of Ecological Niche Breadth