Ivan Kuzmin / Alamy
Why do Venus flytraps and pitcher plants trap and digest insects if they are fully capable of photosynthesis? If this is an adaptation to ensure there is always food, then why don’t other plants do the same? (continued)
Garry Trethewey
Arkaroola, South Australia
That’s a bit like asking: “Why do we need protein if we have carbohydrates?”
Both we and carnivorous plants require a variety of nutrients. Venus flytraps, pitcher plants and sundews tend to live in places that don’t provide certain nutrients (especially nitrogen), and being able to use insects as a nutrient source enables them to survive.
This is a frequently found pattern. Lots of organisms have adaptations so they do well in difficult conditions, where competing organisms don’t survive.
Gabriel Neve
Marseille, France
Venus flytraps, like other carnivorous plants such as Sarracenia (trumpet pitchers) and Drosera (sundews), live in peat bogs and other nutrient-poor habitats.
The captured insects give them the nitrogen, phosphorus, magnesium and other key elements which are in short supply in their environment.
To answer this question – or ask a new one – email lastword@newscientist.com.
Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.
The use of AI tools (e.g. ChatGPT, Claude) to write either questions or answers is forbidden, and any submissions found to have been written using AI tools will be withdrawn.
