Fig and wasp relationship

Mutualistic relationship is maintained : Fig Wasp - AskNature

fig and wasp relationship

Fig trees and fig wasps are partners in life, but sometimes the trees betray their closest allies. Figs and fig wasps have a special relationship that is essential to their mutual survival. The fig provides a home for the wasp and the wasp provides the pollen. Wasps being inside figs is just part of the circle of life. This relationship with the special wasps and the figs is, as the video above explains.

Now begins the C phase, which lasts two to three months. The flowers that receive pollen but no eggs develop into seeds. Flowers that receive eggs undergo a transformation to become hardened structures called galls, becoming nurseries with food and shelter for wasp larvae. The D phase occurs at the end of larval incubation.

This is also when the male flowers start to mature, opening up to expose pollen containers known as anthers. The first wasps to emerge from the galls are wingless males with reduced eyes but large strong mandibles," Palmieri said.

The male penetrates the female with a telescopic penis and fertilizes the female inside the gall. Once they have mated in this way, the males use their mandibles to bite through the fig wall. They then go out through the hole, fall to the ground and die.

A tale of loyalty and betrayal, starring figs and wasps

Leaving the receptacle through the hole made by their brothers, the fertilized females fly away in search of other fig trees, and the cycle begins again. The E phase consists of seed dispersal through the feces scattered by the vertebrates that feeds from figs. The proposed F phase Evidence of the new F phase began to appear over the course of years of observation. These figs were discarded and left out of the research.

fig and wasp relationship

In some cases, larvae that were almost the same size as the fig had eaten almost its entire contents. That's when we decided to investigate what was going on," Palmieri said. In the article just published, I describe insects belonging to five orders and 24 different families that are not fig wasps but that also interact with figs, performing different functions.

These insects may colonize figs during different phases of the tree's lifecycle.

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Some rely on fallen figs to complete their development. Palmieri divided the insects into two categories according to their role in the fig tree's ecology and their potential impact on its reproduction. He called the categories "early fig interlopers" and "fallen fig fauna. The fly larvae migrate to the interior of the fig and feed exclusively on yeast and bacteria brought inside by the pollinating wasp. The flies finish their development inside the fig and leave by the exit hole previously chewed in the fig wall by male wasps.

Butterflies and moths are the most aggressive group of insects in terms of the damage to figs. They lay eggs in the fig wall. In the C phase, their larvae bore through the fig wall and feed indiscriminately on fig pulp, wasps and seeds. The larvae destroy the hanging fig and crawl out to pupate in cocoons attached to branches of the tree.

In the case of fallen fig fauna, explained the FAPESP-funded researcher, the category comprises various organisms that feed on the fleshy parts or seeds of ripe figs not consumed by fruit-eating vertebrates. They take advantage of the window of opportunity created by the figs that fall under the parent tree in the F phase.

Fallen fig fauna consists mainly of beetles that feed on fruit remains. Beetles take advantage of the fig development cycle in various ways. Some colonize figs on the tree in the early C phase.

Then the males and females face very different fates. View image of A male Waterstoniella masii emerging from Ficus stupenda Credit: They bite through the syconium, creating an opening for the winged females to fly out. Their purpose completed, the wingless male wasps die, and the syconium ripens into mature, fruit-containing seeds. Meanwhile the female wasps collect pollen from the male flowers, which have just matured.

They stuff the pollen into specialised pollen pockets, located above the abdomen. The nature of dioecious fig trees creates an evolutionary conflict, one that the fig wasps seem to be losing They then leave in search of another fig syconium.

There they will deposit their cargo of pollen, lay eggs, and start another life cycle. Thanks to their short life cycle of just two months, the fig wasps ensure that the fig trees produce fruit all year round. As a result, in rainforests many birds and animals depend on figs for food, making them keystone species that support the entire ecosystem. By nesting in the figs, the fig wasps indirectly help in maintaining biodiversity and population density.

It is a stable partnership that benefits both members, and the wider ecosystem. But in the case of dioecious fig trees, all bets are off. These trees are far less cooperative.

Fig wasp - Wikipedia

Dioecious fig trees are subtly different to monoecious ones. In particular, their flowers tend to have shorter stalks than those of monoecious species. The wasps can still nest in dioecious trees, but their young can only develop in male flowers The fig wasps have changed along with them. Morphological data shows that wasps pollinating monoecious figs tend to have long ovipositors, while those that pollinate dioecious figs have short ovipositors. Dioecy evolved much more recently, as did the altered wasps.

Fossil fig wasps have been found in England that date from 34 million years ago. They have short ovipositors that are almost indistinguishable from those of modern species associated with dioecious figs. The nature of dioecious fig trees creates an evolutionary conflict, one that the fig wasps seem to be losing.

View image of A Roxburgh fig Ficus auriculata Credit: Female flowers have comparatively long stalks, so the female wasps' short ovipositors cannot reach inside to lay eggs and turn the flowers into galls.

A female wasp cannot lay its eggs in a female flower, so when it enters it commits reproductive suicide Despite this, some female wasps enter the female flowers anyway.

From the wasps' point of view this is utterly futile, as it means they cannot reproduce. At first scientists thought that they might be doing it because the male flowers were not yet receptive, leaving them no other option.

fig and wasp relationship

But in a study published in FebruaryRenee Borges at the Indian Institute of Science, Bangalore and her colleagues found that the wasps sometimes enter the female flowers even when the male flowers are receptive. It turns out that the female flowers attract the wasps by mimicking the scent of male flowers. The fig trees are deceiving the wasps, a Machiavellian strategy that furthers the reproductive goals of the fig tree but spells doom for the wasps.

A female wasp cannot lay its eggs in a female flower, so when it enters it commits reproductive suicide. However, the female flower still gets pollinated and goes on to produce seeds. This raises an obvious question. If this strategy is harmful for the fig wasps, and the figs have been using it for tens of millions of years, why haven't the wasps bailed on the figs, or started fighting back?