Selasa, 01 April 2008

The Titan Arum

by Dawn Sanders

Click to enlarge

Introduction: the spectacular plant.

During September 2004, a crowd of visitors descended on the glasshouses of Cambridge University Botanic Garden, to witness the amazing spectacle of the flowering of the giant Titan Arum (Amorphophallus titanum - pictured right looking like an upside down mushroom), a monumental plant, which originates from the rainforests of Sumatra. In the five days from the first unfurling of the flower over 10,000 visitors came to view this dramatic event. A web cam on the garden’s website allowed
for a wider dissemination of this extraordinary and rarely witnessed occasion. The web cam images attracted over half a million ‘hits’ and the garden received emails from around the world congratulating it on making this botanical event available to a global audience. What lessons does the gathering of these crowds at the flowering of the Titan Arum offer to teachers struggling to make botany a stimulating and exciting topic? And what exactly is a Titan Arum?

The Titan Arum

The massive ‘flower’ of the Titan Arum is in fact an inflorescence of many thousands of tiny flowers embedded in a cream spike called a spadix (Figure 1). Encircling it is a funnel-shaped spathe. This structure reaches its zenith for two days before collapsing. During this time, the accompanying stench of rotting flesh is at its peak, usually overnight for approximately 8 hours. The smell is so bad that the Sumatrans call it the ‘corpse flower’.
This cadaverous smell is emitted to attract carrion beetles or blowflies to pollinate the tiny flowers on the spadix hidden by the spathe.

Plants: the Cinderella organisms of the classroom?
In Britain, Tranter (2004) has recently observed that ‘in too many schools, the wealth of living or once living organisms which pupils are required to study is often reduced to little more than the geranium and the potato’. In addition to this absence of specimens, research has demonstrated that teaching with, and about, plants is considered to be a pedagogical challenge by many biology educators working in today’s classrooms. Key messages from this research are:

  • the aforementioned reduced repertoire of specimens being used in classrooms and laboratories (see Collins and Price, 1996)
  • most children and young people prefer to study animals (see Wandersee, 1986 and
    Kinchin, 1999).

It has been suggested, however, that: ‘plants are generally easier to handle in a classroom situation than animals since they do not bite, run away, or produce odours’ (Hershey, 1990, p. 68). In the light of Tranter’s (2004) observations and the findings of my recent D.Phil study on botanic gardens as environments for learning (Sanders, 2004), in which the impressions of children from three London primary schools were collected and analysed after several visits to the Chelsea Physic Garden, I would suggest that it is precisely these active, odorous characteristics of plants that excite children. Hence, for example, their identification of carnivorous plants, such as the Venus Fly Trap (Dionaea muscipula), as ‘killer plants’ and Ginkgo biloba as ‘the big smelly tree’ (Sanders, 2004). So how might teachers use this research to inform their teaching?

The American biology educators, Wandersee and Schussler (2001) use the term marquee plants, that is plants that draw attention to themselves and capture the imagination, to describe plants to be used in educational contexts. They suggest these are plants that:

  • attract the public’s attention
  • during some or all of their life-cycles, are capable of drawing a crowd at a botanic garden
  • may serve as a doorway to greater public understanding of plants (Wandersee and
    Schussler, 2001, p. 3).

They suggest, that by using marquee plants, educators will draw attention to plants that have previously been overlooked by teachers and learners alike. By utilising internet facilities to access webcam documentation of the Titan Arum’s life-cycle or by taking classes to visit the botanic garden itself to witness the spectacle, teachers can engage their learners with a dramatic botanical event that will impact on learners’ imaginations in ways that a geranium or potato cannot. But since this is a rare occasion, how can teachers make botanical education regularly interesting and dynamic?

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