This is a guest post by Michael Smith.
Relationships are a part of our everyday existence. They are an inescapable reality whether they be between humans or with a pet, or with non-living entities such as food or exercise. Although human beings are intelligent and creative in many facets of their living and problem-solving, we are simply not capable of performing all the tasks essential for survival. Like all animals that exist on this fragile globe, we rely on services that other organisms provide for our survival. More often than not, these services are the result of an ecosystem rich in diversity. To help illuminate this point, let us explore how plants, which humans rely on for edible sustenance, depend on communities for their existence.
Plants have the fantastic and extraordinary capacity to harness energy from sunlight. When a plant splits photons, the energy released is used by flora to breakdown CO2, water and oxygen into carbohydrates. Evolution has enabled plants to perform this task because it is a way of storing energy. Plants can then choose to use the energy contained within the carbohydrate compound at a later date.
Energy alone is not enough to grow and prosper though. Plants also need minerals to build proteins for cellular structures. In order for plants to obtain mineral nutrients, many types of flora rely on insects and other small biota for underground love. Worms and burrowing insects break down organic matter into nutrients available for plant consumption. Furthermore, by travelling up and down the soil profile they create gaps for nutrients, water and oxygen to flow towards the plant’s root zone. As a result, plant growth and therefore human survival is reliant on insects providing aboveground and underground services.
Plants are not simply limited to underground interactions with insects. Fungi and bacteria also help plants flourish. Fungal hyphae (a network of underground filaments), for example, reach far and wide searching for nutrients to concentrate and store. Excess nutrients are exchanged with carbohydrates from some plants, a sort of festive fungi barter system. In addition, fungi interacting with plants can trigger the release of chemicals, which prevent insects from attacking the plant and, in some cases, can signal to predatory insects that a feast of arthropods awaits them on a plant’s leaf plateau.
Nitrogen-fixing bacteria, on the other hand, change nitrogen gas into compounds useable by plants. In the first phase, non-symbiotic bacteria fix nitrogen gathered from the atmosphere with other elements to form nitrogenous compounds (inorganic compounds usable by plants). In the second phase, symbiotic bacteria living within root nodules of a leguminous plant exchange the fixed nitrogen for sugars. This interconnected exchange makes the production of the humble lentil a possibility. Therefore, it seems that for humans to eat fantastic plants full of protein and carbohydrates, we are reliant on skills we cannot replicate, and communities full of tiny life forms!
Exploring the relationships involved in a living, micro community of interconnection can be exciting and rewarding. Not only is it fascinating to find out about previously unknown relationships, but it also gives humans an opportunity to help communities perform more efficiently. A classic example is feeding your soil organic matter. Compost does much more than simply feeding subterranean life. It also binds itself to clay particles, loosening and aerating soil in the process. As a result, rain and insects can transport nutrients to a plant’s root zone with a lot less resistance.
Now, we all know about honey bees and pollination, but consider the fact that solitary bees, hoverflies and blowflies in particular scenarios are considered better pollinators. In wildflower patches throughout Victoria, the most common insect you will find, by a considerable factor, is the hoverfly. This fantastic insect masquerades as a bee by displaying fabulous yellow and black stripes. It does this to convince predatory insects that it’s a bee, reducing the chance of an attack. Hoverflies are the greatest pollinators of Melbourne wildflower patches, transporting pollen to and from a profusion of indigenous wildflower species. As well as pollination, hoverflies have an insatiable appetite for aphids and therefore are deemed a beneficial insect to have in farms and backyards.
The second most common group of pollinators in Melbourne’s wildflower patches includes bees and wasps. Bees are capable of seeing UV light and are subsequently attracted to colours closer to the UV spectrum, including blues and purples. Native Wahlenbergia and Comesperma plants evolved alongside the native bees of Melbourne, before the introduction of the European honeybee. These plants are not only brilliant shades of blue and purple but have smaller flower heads requiring native Australian bees, with shorter tongues, to pollinate them in order to not pierce their tube.
On the contrary, blue-banded bees perform a special behaviour called buzz pollination. By shaking their body violently with powerful wing muscles, pollen is dislodged from plants, such as species in the Dianella genus, which hang onto their pollen very tightly. In many parts of the world, honeybee populations have been decimated by neonoictoid pesticides (that are intended to kill harmful insects) and the Varroa mite. As a result, we may become even more reliant on native insects. In fact, it is plausible we will rely on them to pollinate a significant proportion of our commercially grown crops, as well as our wildflower patches and forest species.
So how can we help these communities of helpful and talented insects? One way is to plant native wildflower patches in your backyard and ideally link your patch to those of your neighbours. Animals love to travel along corridors and insects are more likely to see a food source if the patch is large. Convince your neighbour that native bees will then pollinate their tomatoes and hoverflies will attack the aphids on their brassicas!
You can also build insect motels. Air bee-and-b! These engineered homes are a place for insects to seek shelter, escape from predators, hibernate and allow their larvae to grow. Insects are quite particular about their homely requirements. It is therefore essential to use the right materials to attract the beneficial bees you are after. Blue-banded bees, for example, naturally make their homes in clay banks, and resin bees in branches; therefore, make holes in similar materials when constructing a hotel.
Currently exhibiting at Lentil as Anything in Thornbury, my partner Fiona Mitchell and I are spreading a story about relationships and communities. The story is mostly based around wildflowers in Northern Melbourne; for example, Boomers Reserve, in Panton Hill, which has a profusion of beautiful flowers.
We believe that visual media (photography, documentaries and paintings) are a great way to create an initial interaction with a community member, and to spark interest about this fascinating subject area. From there, a message of deeper understanding can be attached (in our case, with blurbs attached to art work), which will hopefully result in further questions about the fascinating world of ecosystems and insect communities.
Michael Smith is a trained ecologist that currently works in bush regeneration, habitat engineering and environmental education. He is passionate about community engagement and teaching the importance of biodiversity.
Banner image courtesy of Michael Smith.