life-history-evolution
Life-history evolution examines how natural selection shapes trade-offs in an organism's allocation of resources across growth, reproduction, and survival over its lifespan. In plant science, this framework helps researchers understand why plants vary so dramatically in traits like seed size, flowering time, and lifespan — from short-lived annuals that reproduce quickly to long-lived perennials that delay reproduction in favor of vegetative growth. These evolutionary trade-offs are particularly important for understanding how plants adapt to variable or stressful environments, with implications for conservation and crop improvement.
open_in_new WikipediaPubMed · 2026-04-21
Scientists mapped the evolutionary family tree of Cistantheae, a diverse group of flowering plants from western North and South America that thrive in both deserts and high mountains. The study reveals that whether a plant lives for one year or many is strongly tied to climate, and that many species may be naturally suited to survive in a wide range of harsh environments.
Annual vs. perennial life history evolved multiple independent times and is strongly correlated with climate: annuals dominate hotter, drier habitats while perennials favor cooler, wetter ones.
Genomic data from 160+ samples across 48 species revealed rampant gene flow and incomplete lineage sorting, especially among annual Cistanthe species in the Atacama Desert.
Many Cistantheae species occupy wide elevational ranges and show repeated transitions in climatic niche, suggesting broad pre-adaptation to both arid and montane habitats.
