Baylor graduate student discovers passion for Venus flytraps, evolutionary implications
Over four years ago, Baylor College of Medicine graduate student David Magnan was grocery shopping when something unique caught his eye – a Venus flytrap. He purchased it and brought it into his lab, which focuses on molecular and human genetics research.
At first, it was a source of entertainment to see what it’s like in real life (as opposed to the well-known depiction of it in the film Little Shop of Horrors). Soon, Magnan became fascinated by the genetics and evolutionary basis of this carnivorous plant.
These plants require lots of sunshine, so Magnan brought it home so it could bask on his balcony. Today, he houses more than 100 Venus flytraps on his balcony. See a slideshow of photos, and get more quick facts on Venus flytraps below. (Photo credit: David Magnan and Heather Born.)
Facts about Venus flytraps
He provides some basic facts about these uncommon plants.
How many types of Venus flytraps exist?
There is one species, but different breeds. A new seedling is sometimes named as a new breed if it has a different size, shape, color or teeth shape.
What is a typical size of the plant?
The biggest traps on the largest breeds get about two inches long. A whole plant is about 5-8 inches wide, and about 5 inches tall in the summer.
Where do they grow naturally?
The bogs on the border between South and North Carolina are actually the only places where they grow naturally. Since the soil is so nutrient-poor and there is no nitrogen in the soil, they get nitrogen from the insects they catch.
Evolutionarily, they’re so different from other plants. They can photosynthesize like typical plants but they grow so much slower without catching insects because that’s their main source of nitrogen. Some plants take nitrogen from the soil, and some fix nitrogen from the air in their roots with bacteria, these plants need to eat it. They also require distilled water – the minerals in tap water will slowly accumulate and kill them since they’ve adapted to such low salt concentrations in peat bogs.
How does the trapping process work?
It’s a two-stage process. There are hairs inside each trap, and if two trigger hairs are touched within 10 seconds, the trap snaps closed quickly. If it continues to be stimulated, the trap seals shut and starts to produce digestive juices. The two stages are in place to make sure they’re catching a bug instead of a leaf or other false alarm.
Do they have the ability to harm humans? What happens if you put your finger near the trap?
They aren’t strong enough to ever do any physical damage. Even with insects, they can trap the bugs and digest them but they can’t even crush their exoskeleton. They wouldn’t hurt you if you touch them; they are soft and pliant and have the consistency of leaves – maybe a little thicker – but aren’t like rose thorns. People joke that I’m going to develop a huge breed, and they’ll know why I’m not in for work the next day.
What do they eat?
They catch flies and moths on their own, but I also feed them crickets that I buy from a pet store.
What are the implications to genetics?
There’s a small amount of scientific literature with theories about how and why carnivory evolved, and it’s a very interesting example of convergent evolution. Carnivory has evolved independently on almost every continent, mostly pitcher plants. There are also intermediates – plants which can absorb nutrients through their leaves but don’t have active trapping mechanisms. Nutrient absorption through leaves is actually pretty common, active mechanisms to trap insects are rarer.
The Venus flytrap has no relatives and is very complex, and a mystery in terms of how such a complicated mechanism could evolve.
Interested in additional information? Flytrapcare.com is a good source of basic information and forum for flytrap growers.
-By Jordan Magaziner