Science on your doorstep
Pollination articles involve life cycles of flowering plants, complementing the articles on ferns. Native New Zealand examples are used extensively, but introduced plants are included because they are often more accessible for study. Writing these articles gave me a better understanding and appreciation of my own garden and nearby native bush in the Wellington suburb where I live. My garden also became the source for a number of the photographs used to illustrate the articles. Perhaps your students could keep a flowering plant photo diary of their own.
As well as helping students develop their observation skills, pollination spans the Living World strand of the science curriculum.
Pollination is part of the life cycle of flowering plants. If you’re going to explore life cycles rather than just pollination, you may need to spread your studies out over several months. In spring, our kōwhai tree is a riot of yellow, with tūī feeding on the nectar-rich flowers and incidentally pollinating them. At about the same time, the karamū trees are also in flower, but the wind-pollinated flowers are not so obvious. Later in the year, the kōwhai tree is empty of birds, yet the karamū is alive with them, feeding on the bright orange fruit and helping to spread the seeds.
One way to understand the pollination process is to look at some of the strategies plants have developed for attracting pollinators and to avoid self-pollination. You’ll encounter many examples on the Hub but one that stands out for me is a native mistletoe with flowers so specialised that they don’t open unless tweaked by certain native birds. There’s also kiwifruit, which has separate female flowers that produce fake pollen, and we look at kiwifruit pollination problems.
Pollination is intimately connected with the lives of birds, insects and other animals, so we look at the role of pollination in ecosystems from native bush to orchards. These may seem to have little in common, but you’ll find that both illustrate what can happen when an ecological balance is upset.
You’ll encounter aspects of evolution when studying pollination, possibly starting with what makes flowering plants different to other plants. Pollination is about the transfer of genetic information – flowering plants have developed a wide range of forms and techniques to encourage cross-pollination, helping to ensure genetic variation that will help species survival. I had never seen an avocado tree until we filmed in an orchard near Cambridge and was amazed to find that the flowers change sex from day to day to avoid self-pollination.
Nature of science
There are some useful examples of how scientific research can be carried out, including the role of observation and the use of manipulating variables in experiments. The planning of experiments is critical, especially when you’re working with plants that only flower for a short time each year.