Pollen and plants: ecological relationships and reproduction

Carnivorous Plants

Botany, the study of plants, can be a tedious subject given the numerous varieties of plants that are available to study, along with their similarities, and redundancy. However, a bright spot in the plant community is the carnivorous plants, the meat-eaters - the gory plants that science fiction novels are made about. There are almost 600 species of these plants that eat meat growing in the wild, and these plants not only have an intimidating look, but some species can eat "frogs, birds or even small monkeys" (Stiefel 65).

What Makes Carnivorous Plants Different From Regular Plants?

Carnivorous plants are not all that different from regular plants. The posses the abilities to attract insects (or other prey), capture them, kill them, digest them, and absorb the nutrients. Noncarnivorous plants have flowers that attract insects (think bees) and some even can capture insects; some flowers have the toxic compounds to kill insects that are feeding on them, and all plants have molecules that can digest matter, as well as the root systems to absorb nutrients - carnivorous plants just use all of their abilities in distinct, unique ways that allow for them to essentially eat insects. (Rice)

What Kind of Carnivorous Plants Exist, and Where?

Venus' Flytrap is only one of about 600 species of carnivorous plants. Taxonomically speaking, all carnivorous plants are in the Kingdom Plantae, as well as the Division Anthophyta. Anthophyta contains all flowering plants, also known as angiosperms (Rice). The majority of carnivorous plants exist in the class Dicotyledones, though some are monocots (Rice). Because of years of evolution, as well as varying taxonomical changes, there are variations in the order-family-genus arrangements, but the one shown below is provided by Barry Rice, and the International Carnivorous Plant Society.

The Classical Arrangement

FAMILY-

GENUS

GLOBAL DISTRIBUTION

Sarraceniales

Sarraceniaceae

Darlingtonia (1 species) northwest USA

Heliamphora (6 species) north-central South America

Sarracenia (10 species) southeast USA-east Canada

Nepenthales

Nepenthaceae

Nepenthes (89 species)

Indonesia -- Australia, Madagascar

Droseraceae

Aldrovanda (1 species)

Eurasia

Dionaea (1 species)

North Carolina

Drosera (152 species) global

Drosophyllaceae

Drosophyllum (1 species)

Portugal, west Spain

Violales

Dioncophyllaceae

Triphyophyllum (1 species)

West Africa -- Ivory Coast

Passifloraceae

Passiflora (1 species) tropical America

Saxifragales

Byblidaceae

Byblis (5 species) northwest Australia

Cephalotaceae

Cephalotus (1 species) southwest Australia

Scrophulariales

Lentibulariaceae

Genlisea (20 species)

South America, Africa

Pinguicula (78 species)

N. America, Europe, Asia

Utricularia (221 species) global

Martyniaceae

Ibicella (1, non-carnivorous)

South American, a common weed

Bromeliales

Bromeliaceae

Brocchinia (2 species)

South America

Catopsis (1 species)

Florida, South America

Barry Rice, (http://www.sarracenia.com/faq/faq5035.html, Accessed November 17, 2002)

Venus' Flytrap, In More Detailyoung Venus' Flytrap, from Botanical Society of America (http://images.botany.org)

Because the Venus' Flytrap is the most well-known, easily recognizable carnivorous plant, it is one of the easiest to explain in detail. As well as being relatively popular, the Venus' Flytrap is also one of the more gruesome carnivorous plants, as well.

To start, the leaves of Venus' Flytrap (Dionaea muscipula) have short, stiff hairs on the edges that are called trigger hairs (BSA). When any stimulus touches one of the hairs enough to move it, the leaves snap shut, which traps whatever is inside. If the object is not an insect, but rather a rock, or leaf, the leaves reopen in about twelve hours and "spit" the item out.

Once the trap is closed, there are cilia that keep the large insects from being able to escape. These cilia are look like fingers on the outside of the leaves, which interlock much like our fingers would if we were to clasp our hands together.

Within a few minutes, the trap shuts tightly, forming an airtight seal around the insect which keeps bacteria out, and the digestive secretions in (Stone).

For the next week, or so (depending on the size of the insect, as well as temperature conditions) the plant secretes digestive fluids that help dissolve the inner part of the insect, leaving behind the outer exoskeleton. Once the insect is dissolved, the trap reopens, and wind usually blows away the leftover exoskeleton.

The Venus' Flytrap is found in North Carolina, and grows to be around 12-25 cm tall (Stiefel 66). Insects are attracted to the plant by the sweet nectar and red interior that shows when the leaves are opened.

Carnivorous Plants, Conclusion

Carnivorous plants are not dangerous to humans, or household pets for that matter. There are some reports, as noted earlier, of one particular type of carnivorous plant - the Nepenthes pitcher plant (Asian jungle vine) that has eaten large frogs, some birds and even small monkeys (Stiefel 66). However, these reports are rare, and the birds and monkeys were most likely already sick. The vine can grow to be over ten meters long, making it a rather large carnivore, but harmless to humans nevertheless (Stiefel 65).