Thermogenesis, or the ability of plants to generate their own heat, is a unique survival adaptation found in some plant species. While often linked to animals, this process helps certain plants, such as cycads and specific flowering varieties, attract pollinators.
How Plant Heat Attracts Pollinators
Plants that generate heat can release their fragrances more effectively. This enhanced scent dispersal increases their chances of attracting various pollinators, including beetles, flies, and thrips. The internal heat not only makes these plants more attractive to insects but also supports the development of reproductive organs like flowers and pollen tubes, especially in cooler climates. This provides a significant advantage over plants that do not produce heat.
Challenges in Studying Thermogenesis
Studying thermogenesis in plants is challenging because heat cannot be preserved in the fossil record. Scientists rely on indirect evidence, such as fossilized anatomical structures that might have supported heat production. By comparing the anatomy of ancient plants with modern thermogenic species, researchers can infer how heat generation may have evolved.
New Insights from Recent Research
A recent study by the Botanical Institute of Barcelona (IBB), in collaboration with several institutions including Complutense University of Madrid, the Geological and Mining Institute of Spain (IGME–CSIC), the Smithsonian Institution, the University of Barcelona, and the Royal Botanic Gardens of Sydney, has shed new light on thermogenesis. The research revealed that thermogenesis might be older than previously believed.
David Peris, a researcher at IBB, stated, “Our findings suggest that thermogenesis in plants could have been a key factor in the evolutionary success of seed and flowering plants, as well as their pollinators, dating back 200 million years.”
An Evolutionary Advantage
Thermogenic plants often have female reproductive structures that mature before male ones, which prevents self-fertilization. Fossil evidence shows that early flowering plants might have had features like independent closing of stamens and carpels, which could trap pollinating insects. Additionally, large reproductive structures, such as perianths or cones, that retain heat suggest that thermogenesis might have provided an edge over non-thermogenic plants during the Mesozoic era.
Impact on Plant and Pollinator Diversity
Iván Pérez-Lorenzo, a co-author of the study, remarked, “Thermogenesis is more than just a botanical curiosity. It has significantly influenced the success of both insects and flowering plants.” The study opens new avenues for exploring how thermogenesis has impacted plant-pollinator relationships and their evolution.
Implications for Climate Change
The discovery of thermogenesis as a critical factor in early plant survival offers valuable insights into plant evolution. Understanding how heat generation has shaped plant-pollinator interactions over millions of years could provide clues about how plants might adapt to future climate changes and environmental pressures.