We know we need to look after our bees, but what about wasps? University of Bristol researcher Daisy Taylor tells us more about this essential little insect…
When I tell people I work with wasps, I inevitably get one of two reactions; most people will tell me how much they love bees, while others recoil in horror and tell me how much they hate wasps. The ecological and economical services provided by bees are plentiful, and have been well documented. There’s no doubt that, in contrast, wasps get a bad press, but is this justified?
The common yellow jacket wasp (Vespula vulgaris) is the bane of picnics across the UK, but there are well over 110,000 species of wasps worldwide, with an estimated 100,000 more still to be identified. This hugely diverse assemblage belongs to the order Hymenoptera, which also includes ants and bees. Bees are excellent pollinators, while ants are ‘ecosystem engineers’, dispersing seeds and cultivating soil. I often get asked if wasps pollinate, and the short answer is yes! Just like bees, adult wasps need carbohydrates from the sugars found in nectar, and so they travel between flowers collecting and transferring pollen in the joints of their exoskeleton and on the tiny hairs on their antennae and legs.
Unlike bees however, wasps aren’t limited to specific flowers for pollination, they can collect nectar from any flower. In contrast, the proboscis of bee species vary in length, meaning each species is limited to certain flowers. This is important in fragmented habitats (such as agricultural or urban areas), as often a greater number of wasps can thrive, making them crucial as backup pollinators in degraded habitats.
The most important role of wasps, both economically and ecologically, is that of pest controller. While bees feed their larvae pollen, wasp larvae require protein for development. To supply this, adult wasps are voracious predators, feeding on a number of other insect species including aphids, centipedes, mites and spiders. Wasps are generalist predators, at the top of the invertebrate food chain, where they regulate both carnivorous and plant-feeding insect populations.
The presence of wasps has been shown to reduce the number of aphids by over 3x, without the need for chemical pesticide applications. A single yellow jacket has been shown to consume over 8kg of prey per hectare per season and these wasps, along with many other species, live in social groups which can contain up to 10,000 of these pest-controllers!
While it’s not currently possible to accurately determine their huge economic and environmental value in regards to pest control, their diet of agricultural pests make wasps crucial to global food security. So next time that wasp is ruining your picnic, please take a moment to appreciate their important role as pest controller and pollinator, before you take a swipe at them!
More about Daisy
Daisy Taylor is a post-doctoral researcher at the University of Bristol, working with Dr Seirian Sumner at UCL. She presented a fantastic talk at Pint of Science Bristol 2017 about her research on wasps and their important role in ecology.
Her research looks at the genetic mechanisms by which wasps have evolved to live in complex societies. Along with ants, bees and termites, wasps have evolved social behaviour; defined as species which show a division of labour, where one or a few individuals in the group is responsible for reproduction (queen), while all others are sterile (workers). Sociality is an incredibly successful evolutionary trait that has helped these insects colonise every continent, with the exception of Antarctica.
Wasps show the most diverse array of social behaviour: from solitary species where a single female builds her nest, reproduces and provides for her brood; to simple societies in which all females look identical and workers can become queens through aggression; to highly social species where the queen is determined during development, is physiologically distinctive and workers will remain sterile throughout their lifetime.
By looking at wasp species at different stages of sociality, we hope to identify the genes, proteins and molecular mechanisms involved in this highly successful evolutionary transition.