A biology class in a lecture mode can sometimes result in conclusions that may contribute to wrong or incomplete knowledge being created. I realized this when I was showing a child of class 6 a lemon tree and the thorns in them. There was an immediate reaction, “I thought thorns were present only in plants in deserts or in plants which do not have leaves.” Her teacher had perhaps failed to clarify in her lecture that thorns are not always reduced leaves. Misconceptions like this are galore while learning about plants. One such example is the topic of this article – plants that are generally referred to as succulents. I specifically recall that in my college, I was taught that succulents can be found only in places where water availability is low, and deserts given as an example of the habitat. It is precisely this, the habit of giving just one or one kind of example to explain concepts that leads to wrong associations, establishing wrong knowledge in the mind. I learned how misleading that statement was only years later when I started to take my students on field trips to teach biology.
Succulents is a term that describes plants which have developed the ability to store water in their tissues, to be used during conditions of water scarcity. It is no doubt true that succulents are more common in regions that are hot, arid, or dry, but they may also be found in forests and wet areas, hills and high altitude regions, and even in cold environments. This plant Portulaca pilosa shown above was growing inside the forests of Western Ghats. What about xerophytes? Are they succulents? They also grow in dry arid habitats!
Not all xerophytes are succulents; so again room for misconceptions. Questions are rarely raised, right kind of questions seldom asked, and examples provided are not familiar and lack in diversity. For e.g., a question such as, “Are succulents xerophytes?” can throw up a lot of examples for discussions, resulting in clarifications. There are similarities and differences between succulents and xerophytes. Succulents are among the most interesting ones to study and easy to grow to be a subject of study for a science project.
There are more than 60 families that have succulent plant species. This article focusses on plant species belonging to the Family Euphorbiaceae. According to N.P. Balakrishnan and T. Chakrabarty – Family Euphorbiaceae is a complex heterogeneous family consisting of about 322 genera and 8900 species in the world. In India, this family is represented by 73 genera and 410 species. Species belonging to genera Euphorbia, Jatropha and Pedilanthus are plants that may be seen even in our gardens. A group of commonly seen plants that are often mistaken for the cactus belong to the genus Euphorbia. There is an interesting anecdote about this name. This name Euphorbia was suggested by King Juba II of Mauretania (ca. 50 BC – 19 AD). The plant with its fleshy latex containing tissues reminded the learned King (a botanist of great repute) of the plump appearance of his Greek physician whose name was Euphorbus. He named the plant after the physician.
The author is a consultant for science and environment education. She can be reached at firstname.lastname@example.org.