Field of Science

Who gives a fig?

Rachael Roscata asks: "So not to go on a tangent and cause a billion questions beginning with "Well what about...", but what about a fig? Is it a fruit?"
Well, the Phactor doesn't have to go out on a limb (?) to answer this. A fig is a real fruit, but a very strange one. Rachel found the Phactor's 3-yr-old blog about whether an artichoke was a fruit or a vegetable, a blog read by over 5,500 people since the software began keeping track of traffic.
A fig is a multiple fruit, and an accessory fruit, one composed of a whole inflorescence of flowers that develop enmass into a single fruit. A fig is a synconia, a bulb-shaped receptacle, a modified stem bearing many flowers on its inner surface, so you never see fig flower unless you cut the whole synconia open. So how do it get pollinated? Tiny wasps live and reproduce inside the synconia. Male figs don't produce fruit but they provide a brood substrate for wasp larvae and pollen, which is carried upon female wasps seeking new synconia in which to lay eggs. The pollinated female flowers produce the edible fruits, each flower resulting in a single seed. Each species of fig has a specific and different species of wasp, an interesting evolutionary dance where each species needs the other for its reproduction. Fig flowers are very small, so the actual flower-fruit would be just one of the sort of stringy units within a fig, but the receptacle also develops into fleshy tissue. As pointed out in the artichoke blog, accessory fruits include fleshy tissues associated with the flower or flowers. But Rachael was pretty perceptive in thinking that a fig was a pretty strange fruit. Well, what about that! Try not to think about what happens to the wasps after pollination, but you know those little crunchy bits? They're seeds.