Thermogenic plants have the ability to raise their temperature above that of the surrounding air. They can generate their own heat and flower earlier in the season than almost any other plant. Botanists are not completely sure why thermogenic plants generate large amounts of excess heat, but most suspect the flowers may be doing this to attract coldblooded insect pollinators. Thermogenic plants are found in a variety of families, but Araceae in particular contains many such species. Here’s some examples.
Symplocarpus foetidus, commonly known as skunk cabbage, is a low growing plant that grows in wetlands and moist hill slopes of eastern North America. Bruised leaves present a fragrance reminiscent of skunk.
Skunk-cabbage in snow – Photo via Ryan Johnson/Flickr
By Sue Sweeney. – The Monday Garden. Archived at http://ontariowildflowers.com/mondaygarden/article.php?id=158, CC BY-SA 3.0, Link
Skunk Cabbage peeking through the snow – Photo by John Winkelman/Flickr
Skunk Cabbage through snow – Photo by Justin Meissen/Flickr
Helicodiceros muscivorus, the dead horse arum lily, is an ornamental plant native to Corsica, Sardinia and the Balearic Islands. Its flowers smell like rotting meat, attracting carrion-seeking blow flies which act as pollinators.
By Göteborgs botaniska trädgård (photographer: Ingemar Johansson) – http://www.mynewsdesk.com/se/pressroom/goteborgs_botaniska_tradgard/image/view/dracunculus-muscivorus-128973, CC BY 3.0, Link
Amorphophallus paeoniifolius, the elephant foot yam or whitespot giant arum, is a tropical tuber crop grown primarily in Africa, South Asia, Southeast Asia and the tropical Pacific islands. The plant blooms annually around the beginning of the rainy season. The flower bud emerges from the corm as a purple shoot. While the flowers are in bloom they also produce heat. They die after five days.
Nelumbo nucifera is also known as Indian lotus, sacred lotus, Egyptian bean or simply lotus. Researchers report that the lotus has the remarkable ability to regulate the temperature of its flowers to within a narrow range just as humans and other warmblooded animals do.
Amorphophallus titanum, also known as the titan arum, is endemic to Sumatra. Due to its odor, which is like the smell of a rotting corpse, the titan arum is also known as the corpse flower or corpse plant. Through a series of chemical reactions, the central spadix of the plant heats up to emit and distribute an atrocious stench to attract pollinators, thought to be carrion beetles and blow flies.