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A Practical Guide to Phylogenetics for Nonexperts
Published on: February 5, 2014
Alternative adaptations, speciation, and phylogeny (A Review).
1Smithsonian Tropical Research Institute, Balboa, Panama.
Summary
Alternative adaptations, where one genome produces different phenotypes, allow species to occupy multiple niches. This can drive rapid evolution, speciation, and the origin of major evolutionary novelties.
Area of Science:
- Evolutionary Biology
- Genetics
- Ecology
Background:
- Alternative adaptations involve different phenotypes within a population, arising from the same genome.
- These adaptations allow a single species to exploit multiple ecological niches simultaneously.
- They are crucial for understanding evolutionary novelty and speciation.
Purpose of the Study:
- To synthesize evidence on the prevalence and significance of alternative adaptations.
- To highlight their role in generating evolutionary novelties and driving speciation.
- To propose a revision of traditional views on organic diversity.
Main Methods:
- Review and synthesis of existing evidence from diverse organisms.
- Theoretical exploration of the evolutionary consequences of alternative phenotypes.
- Comparative analysis of evolutionary patterns.
Main Results:
- Alternative phenotypes are common across various taxa.
- Selection for dissimilarity between alternatives promotes novel adaptations.
- Sudden fixation of alternatives can lead to rapid morphological evolution and punctuated speciation.
Conclusions:
- Alternative adaptations are a significant, underappreciated force in macroevolution.
- They challenge traditional models of gradual evolution and speciation.
- Behavior and ontogeny play key roles in the genesis of organic diversity through alternative adaptations.
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