Natures wonders: a new plant carnivore (Introduction)

by David Turell , Tuesday, August 10, 2021, 14:51 (1199 days ago) @ David Turell

Only part time:

https://www.sciencemag.org/news/2021/08/meat-eating-plant-only-part-time-killer?utm_cam...

"The species in the new study, called the western false asphodel (Triantha occidentalis), lives in mountainous bogs and other nutrient-poor locations in western North America. The upper part of its flowering stalk is covered with small red hairs that exude a shimmering, sticky substance. The hairs often trap flies and small beetles in the droplets. But so do many other kinds of plants, which use these hairs as defense against pests rather than as a source of nutrition.

"Qianshi Lin, then a Ph.D. student at UBC, decided to investigate. He prepared a special diet for Triantha: fruit flies that had been fed with an isotope, or form, of nitrogen that is rare in nature, which could reveal whether the plants were absorbing nutrients from the flies. After 150 flies had matured, Lin froze them. Then, he and colleagues visited a bog near Vancouver, where they added fruit flies to 10 individual Triantha plants and, as a control, to a similar-size plant that is not carnivorous.

"One to 2 weeks later, the researchers brought the plants back to the lab. They could detect the nitrogen isotope in the stems, leaves, and fruits of Triantha, but not in the noncarnivorous plants. Triantha got more than half of its nitrogen from prey, similar to sundews, a carnivorous plant living nearby, the team reports today in the Proceedings of the National Academy of Sciences.

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"Many carnivorous plants use sticky hairs to snare flies and small beetles, but they locate these traps away from their flowers—it’s no good to eat an insect that’s needed for pollination. The western false asphodel doesn’t do this; it puts these sticky hairs on the main stem bearing its flowers, which grows up to 80 centimeters tall. The authors think the red hairs and shiny droplets attract insects, like in sundews, but the hairs and droplets are small enough that they can’t trap bees or other pollinators.

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"Triantha is just a part-time carnivore, Lin says, because it only flowers briefly. Aaron Ellison, an ecologist at Harvard University, notes there’s only one other known example of a part-time carnivorous plant, a vine in West Africa that eats insects only as a juvenile but then outgrows the habit.

"There’s something else remarkable about Triantha, Ellison notes: It’s one of just a few examples of carnivorous plants in a large group of plants called the monocots (which includes all grasses and lilies, for example). Why are carnivorous monocots so rare? Lin says it might be because the typical monocot leaf, like a blade of grass, is narrow with parallel veins, which may be less suitable for evolving into complex traps."

Comment: Not like Venus!!! Venus and others like it need insects to get enough nitrogen, not readily available in the soil it lives on.