Bees get a lot of credit — and rightfully so, as they pollinate flowers and are essential to human agriculture, as well as countless ecosystems. But other pollinators also exist; in fact, hundreds of wasp species are vegetarian and only feed off pollen and nectar. While not as efficient in pollination as bees, wasps also have a role to play.
Pollination is the process of making plant babies. Essentially, it’s the act of transferring pollen from the male anther of the flower to the female stigma. It sounds so simple yet successful pollination needs all strings to be perfectly pulled as the synchronicity of blooms and sufficient presence of pollinators must go hand in hand. The process is neglected surprisingly often, especially considering that so much of our diet and economy depends on it.
Among the animals we most of the time associate with pollination are the bees. Bees make excellent pollinators because they are dedicated to collecting pollen, a source of protein that they feed to their developing offspring , and they also have furry bodies, which means they attract more pollen. But what about the other pollinators?
Bastards, but useful bastards
Wasps are the underdogs of the pollination scene. Earning a bad reputation for themselves because of their remarkably painful stings and aggressive behavior, they are also important catalysts of plant reproduction.
Many wasps are apex predators so if they’re not in good shape, there must be something wrong with the ecosystem — which is quite alarming. Just like bees, the number of wasps is declining drastically, prompting concern among researchers.
Wasps belong in the same order (Hymenoptera) as bees and ants. At a glance, they look very similar to bees but wasps are generally not covered with fuzzy hairs, making them less efficient at pollinating flowers since pollen is less likely to stick to their bodies. They visit various flowers because, like bees, they also need key resources such as pollen and nectar.
Wasps can be, as they say, bastards. They’re particularly cruel and sinister apex predators, capturing insects or spiders and often not killing them instantly, but paralyzing them using a venomous sting. They often chop up their victims and feed them to their larvae — often while the unfortunate insect is still alive.
But they still play an important role in the ecosystem. Without wasps, many ecosystems would be overrun by flies and spiders, which makes wasps a sort of regulator of ecosystems. They also help reduce some crop pests, making them a gardener’s friend (at least sometimes). But pollen wasps (as the vegetarian wasps are called) can destroy flowers and fruit in their search for food, which makes them less of a friend to gardeners.
Unlike bees (which can only sting once and sacrifice their life for that sting), wasps can sting as many times as they want — which makes them more inclined to, you know, sting. The sight of a wasp is almost always followed by the threat of being stung by a wasp. But there is justice in the world; one organism has found a way to completely turn the tides against wasps. I’m talking, of course, about figs.
The dark magic of figs
Among the numerous wasp groups is a family called Agaonidae — but most commonly called fig wasps. This group has coevolved with figs, being an excellent example of mutualism: an interaction between different species that in the long run, helps both species.
Have you ever seen a fig tree flower before? Probably not, or at least now in the way you’d expect it. Fig trees have no visible flowers. What we normally call fruits are actually inverted flowers.
Technically, the flowers are hiding in a structure called syconium — this is what most people think is the fruit! To put it simply, what we call figs is not a fruit but an inverted flower. The flowers bloom inside the pod and then produce a one-seeded hard-shelled fruit that is called an achene. This gives the fig its signature crunch.
The unique flower-to-fruit development of this plant indeed calls for a specialized pollinator. Drumroll, and imagine a wasp coming in a cape to save the figs’ day.
The magic of fig pollination begins when immature flowers from the inside emit an enticing scent that attracts only female wasps. The female wasp enters the male fig (which we don’t eat) for the purpose of laying its eggs. The male fig is perfectly designed for this as a breeding site for wasp eggs. An intense struggle begins for the wasp, as the insect pushes its way through the small opening called ostiole. Going through this tight passage is not a walk in the park as the wasp usually loses its wings and pieces of antennae in the process, often becoming trapped inside the pod until it dies. The humble fig has found a way to turn the tides on one of nature’s most fearsome predators!
The baby wasps are then the ones to continue the cycle. Male offspring do not possess wings as they are programmed only to mate with the female wasps. It is the females that are equipped with wings and antennae allowing them to journey out into another fig and bring pollen with them.
As it ventures out, the fig wasp may enter a female fig accidentally which has no room in the interior for reproduction. As it is trapped in there, pollination occurs with the pollen from the male fig being spread to the female fig which in turn produces the fruit that we love to eat. Basically, it is the female figs that are palatable as male figs are full of larvae. This remarkable partnership is very well designed and is often cited as a fine example of plant and pollinator coevolution. Remarkably, some wasps become parasites of this system, but they too play a role that somehow helps this partnership.
Parasitic fig wasps use a long egg-laying tube to pierce the outside of the fig and lay its own eggs into the ovules of the fig wasp eggs. The larvae of this parasitic wasp want to eat the young of the fig wasp. But the egg-laying tube isn’t long enough to reach all the way to the core of the fig, which means that in order to escape the parasite, the fig wasp must lay its eggs in the deepest part of the fig. This leaves the outer fig ovules free to develop into seeds and create the next generation of trees — without this, the fig wasp larvae would devour too much of the fig and would threaten the figs’ development.
Figs dominate the tropical forest and are arguably known as the fast food of the forest due to a number of birds, mammals, and reptiles relying on it. It is undeniable that fig wasps play a crucial role in maintaining fig trees and ensuring their propagation. Wasps may not be as efficient as bees in pollinating a range of flowers but they do have their own niche that certainly deserves recognition too.
Ultimately, wasps aren’t the most charismatic of creatures, and that’s okay. They’re some of the cruelest predators out there, and they can also be annoying to humans. But wasps are a very diverse group, and sometimes, they also play an important role. They can be pollinators and have developed a unique relationship with figs — and we’re still learning new things about them. At the very least, they deserve a bit of our respect.
