I have a dilemma. I like the clivia flowers In my garden. But so do the snails – for different reasons. I don’t normally eat them. So I vacillate between killing the snails and allowing nature to take its course.

We all know we should really garden with nature – not against it. On a daily basis the media exhort us to buy insecticides and a myriads of other poisons to disinfect our gardens. The result? Sterile gardens without bees, butterflies or those magical little fireflies. The reason why I’m so conflicted about killing slugs and snails is because it’s exactly what firefly larvae like to do. They are voracious predators of those slimy garden “pests”. Not pests to them, but food.

How often do we go out into our gardens at night, without a light? How likely are we to see the glow of a glow worm in the leaf litter? Do we even have leaf litter in our manicured gardens? The fact is that we are so conditioned to “gardening” that we banish nature from our environment and our lives.

Fireflies have been on my mind the last couple of weeks as Whale Coast Conservation took groups of enthusiasts to the Fernkloof Nature Reserve to see the magical “Christmas lights” display of flashing firefly lights after dark. Our local firefly species is a tiny beetle no bigger than a grain of rice. It’s hard to believe that such a tiny body can produce such bright flashes, but of course light is produced in photons, which have the same light energy whatever the source.

But why do they produce flashing lights? It’s all part of the mating ritual. Females sit around on vegetation while males fly low, flashing their specific light pattern. If a female likes what she sees, she will flash right back. The rest is history.

She will lay her eggs in damp leaf litter, the eggs will hatch into a larva (in the case of moths and butterflies this will be the caterpillar). The larva eats voraciously until, after a while, it turns into a pupa. Now the most amazing thing happens in the pupa. The cells that made up the larva “dissolve” into a soup and the contents are reassembled into a completely new form – the adult insect, which, in the case of the firefly, is a beetle. Caterpillars of course become moth or butterfly adults. Then the life cycle, known as metamorphosis, starts again.

Have you ever wondered why 85% of all insect species undergo metamorphosis? There has to be some evolutionary advantage to being able to shape shift at various stages of life – from adult to egg, to larva, to pupa and back to adult.

Indeed, there are clear advantages.

For one, the larva and the adult don’t compete with each other for food or space as they have different food requirements and very different ecological niches. Most adult fireflies don’t eat much at all, maybe just partake of the spot of pollen or nectar. On the other hand the larva’s life is devoted to eating. This is my dilemma with the snails and the clivias: do I allow the snails free rein in case there are ‘glow worm’ larvae to eat them. Or do I take care of the little fiends myself and destroy any chance of having firefly larvae in my garden that will pupate and eventually emerge as fireflies? A catch 22 situation.

Another evolutionary advantage of shape-shifting is that adult insects have only one thing on their mind. Unlike the larvae that stay put in one place gorging on vegetation, the adults do what adults do – procreate. Many of them have wings and can thus fly to seek mates or disperse the species. What a neat division of labour – one shape eats, the other shape goes forth and multiplies.

No wonder insects have been around for millions of years – and will be for many more.

About the Author

 

Whale Coast Conservation passionately lives by its slogan “Caring for your environment”.

Its small staff and volunteers are dedicated to

  • raising community and visitor awareness of the unique, biodiverse natural resources of the Cape Whale Coast region and
  • to projects that convert awareness into practical actions that lead towards living sustainably.

WCC ensures expert representation in public participation processes that contribute to environmental and developmental policies and legislation.  We monitor regional development; and ensure compliance with legislation and guidelines.

WCC increases general public awareness of sustainability through environmental education, citizen-science research projects, community projects and campaigns.

WCC communicates with its audience through exhibitions, signage, technology demonstrations, workshops, talks, film shows, newsletters and articles.

WCC places emphasis on educating future generations through its Youth Environment Programme (YEP).  YEP is offered to 24 schools in its target area with a total of over 10,000 learners.

WCC facilitates schools’ participation in special events such as Earth Day, Walking for Water, Arbor Day and Coastal Clean-ups.

WCC facilitates educator development programmes to improve the capacity of educators to offer informed environmental content in their lessons across all learning streams

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