A strange, mutualistic relationship exists between figs and wasps: Figs rely on wasps to pollinate the inside-the-fruit flowers, and fig wasps require a safe place to lay their eggs.
As a result, fig wasps burrow into fig fruits to lay their eggs. Due to this process, the wasps lose their wings and antennae, and the female wasps die inside the figs.
Wasp eggs hatch when they reach maturity, and male offspring mate with female offspring. The wingless males also perform their duties by burrowing tunnels for the pregnant and pollen-laden female wasps to exit and restart the cycle.
So, why don’t we see more wasps in our figs? Because some domesticated varieties of common figs, for example, are seedless and require no pollination.
Others are divided into male and female trees, with wasps pollinating only the male trees. Even if wasps get into the fruit, the insect bodies are easily digested by fruit enzymes. As a result, the fig and the wasp eventually merge into one. Tasty!
When You Eat a Fig, Are You Eating a Wasp?
Whether we eat fig wasps when we eat figs is a common question among fig lovers. For dried figs, the answer is yes; for fresh figs, the answer is usually no.
Figs grown for dry fig production are usually pollination (caprification) cultivars, such as the Turkish Sari Lop or Smyrna figs, that have a nutty flavor and seeds, as opposed to the sweeter fruit of parthenocarpic varieties, which are much softer and lack seeds (Armstrong, 1988; 2010; Tribolet, 1912).
These Smyrna cultivars have the same fruiting phenology as wild female trees.
As a result, the pollinator has been introduced to various parts of the world where Ficus carica is grown to increase fig production and supply to the dry fig market (Mars, 2003).
In many areas, however, these cultivars are gradually being replaced by non-pollinating cultivars to avoid sanitary issues, such as pollinator transmission of internal rot fungus and costs (Kjellberg, F. van Noort, S, Rasplus JY. In press).
Female fig wasp pollinators enter the fig via the ostiole (the opening at the fig’s apex) to pollinate the flowers and lay their eggs down the style into the flower’s ovary.
Ficus carica is a functionally dioecious species, meaning that the species’ male and female reproductive functions are separated among individual trees, with some trees being female and others male.
Male trees produce a couple of seeds but mostly wasps, whereas female trees produce seeds in the figs but no wasps. The wasps then load up on pollen before dispersing from the fig they’ve bred in, performing the species’ male function.
Suppose figs from female trees of cultivars that require pollination, such as the Smyrna fig, are used in fig production.
In that case, wasps may be eaten because the foundress females that entered the fig to pollinate the flowers commonly do not manage to exit the fig again.
Female wasps will occasionally escape from the fig they entered. Because the floret styles are too large for the female’s ovipositor to reach the ovule to lay an egg, the wasps cannot reproduce in the fig, and only seeds are produced by her pollination of the stigmas, with these figs serving as the species’ females.
Fig Wasps Aren’t Harmful to Humans
The enzyme ficin, which breaks down the female exoskeleton, is found in figs. Well, for the most part. You technically eat the wasp when you eat a fig pollinated by mutualism.
However, fig wasps are very small, measuring only 1.5 millimeters in length. So, if you get a few un-enzymed wasps with your fruit, it’s not a big deal compared to the bug content in other foods.
Your hoppy beer probably has more bugs than your figs. According to Scientific American, the FDA’s aphid limit in hops is 2,500 aphids per 10g hops or about 5% of the total weight of the hops.
What About Wild Figs?
Many indigenous people eat wild figs because they are very nutritious. The fig wasps that haven’t left the fig they bred in are eaten along with the fig in these cases.
Most fig wasps will have left the fig before it ripens and attracts frugivores, but some species have wingless males that die and remain within the fig cavity.
Within the fig cavity of wild figs, there are also nematode worms specific to fig wasps and a variety of other fungal organisms, but none of these appear to be harmful to human health.
How Does the Fig Wasp Pollinate?
The fertilization procedure is as follows: A female wasp enters the male fig to lay her eggs through a small passage.
The female’s wings and antennae break off due to the narrow passage. As a result, there is no way out once the female has entered.
The female wasp then lays eggs inside the male fig, resulting in male and female wasp babies.
The only two purposes of male babies are to reproduce with female babies and dig tunnels for the females to exit the figs.
The pollen-laden female babies then leave their figs, searching for a new fig to nest in. The cycle continues. (I know, it sounds like a botany-themed Game of Thrones episode.)
The male figs are not eaten. When a female fig wasp accidentally enters a female fig carrying pollen, we get fig “fruit” (technically flowers). The fig flower grows inside after she pollinates it. Remember that a wasp loses her antennae and wings when she enters a fig, so she’s doomed to die inside… We also get some delicious figs as a bonus.
Figs Without Wasps?
More than 94 percent of figs produced and sold commercially in California are self-pollinating, according to Karla Stockli, CEO of the California Fig Advisory Board.
Fortunately, many of the figs we buy in the United States come from California.
Stockli explains, “California produces 100% of the nation’s dried figs and 98 percent of the fresh figs under the most prominent growing conditions and highest quality standards in the world.”
The majority of commercial figs, such as those sold in stores, are grown without wasps. While wasp bodies may add crunch to a tasty fig, you’re unlikely to find a wasp inside the fig you’re about to eat, even if you look closely.
Some fig varieties grown for human consumption have ripening figs that do not require pollination. Plant hormones can also be used to trick plants into ripening figs without the use of wasps.
Even if you grow figs with wasps the old-fashioned way, the wasp is long gone when the fig reaches your lips.
The wasp bodies are broken down by a chemical called “ficin,” which is produced by figs. Ficin is so good at breaking down (or digesting) animal proteins that Central Americans use fig sap to treat intestinal worm infections.
So, no, those store-bought fig-filled cookies aren’t full of dead wasps. But don’t give up hope. If you’re serious about eating insects, Ask-A-Biologist has some excellent recommendations.
Are Fig Wasps Aggressive?
Animal fights are common, but they rarely result in death because the benefits of winning rarely outweigh the costs of losing.
However, lethal combat can develop when the contested resource determines a large portion of each combatant’s future reproductive success. Female agaonid fig wasps pollinate and lay eggs in the flowers of fig trees’ enclosed inflorescences (or “figs”) ( Ficus spp.).
Wasps rarely leave the first fig they enter, so each “foundress'” reproductive success is largely determined by the availability of flowers within a single fig.
In the undescribed Pegoscapus sp. that pollinates Ficus citrifolia in southeastern Brazil, we report lethal combat between female agaonids for the first time.
Wasps showed no aggression outside or inside the fig in staged dyadic contests until one of the foundresses oviposited. The first wasp to oviposit then became aggressive, killing its competitor in most cases.
According to an examination of dead foundresses in naturally occurring figs, injuring competitors, particularly through decapitation, effectively reduced their oviposition rates.