The story of the fig and its wasp

Inside the rounded fruit of a fig tree is a maze of flowers. That is, a fig is not actually a fruit; it is an inflorescence—a cluster of many flowers and seeds contained inside a bulbous stem. Because of this unusual arrangement, the seeds—technically the ovaries of the fig—require a specialized pollinator that is adapted to navigate within these confined quarters. Here begins the story of the relationship between figs and fig wasps. The queen of the fig wasp is almost the perfect size for the job—except, despite her tiny body, she often times will lose her wings and antennae as she enters through a tight opening in the fig. “The only link the fig cavity has to the outside world is through a tiny bract-lined opening at the apex of the fig, called the ostiole, and it is by means of this passage that the pollinating fig wasp gains access to the florets,” as described in Figweb, a site by Iziko Museums of Cape Town. Once inside, the queen travels within the chamber, depositing her eggs and simultaneously shedding the pollen she carried with her from another fig. This last task, while not the queen’s primary goal, is an important one: She is fertilizing the fig’s ovaries. After the queen has laid her eggs, she dies and is digested by the fig, providing nourishment. Once the queen’s eggs hatch, male and female wasps assume very different roles. They first mate with each other (yes, brothers and sisters), and then the females collect pollen—in some species, actively gathering it in a specialized pouch and in others, accumulating it inadvertently—while the wingless males begin carving a path to the fig’s exterior. This activity is not for their own escape but rather to create an opening for the females to exit. The females will pollinate another fig as queens. The males will spend their entire lifecycle within a single fruit. While this tree-wasp relationship may not be common knowledge to all fig-eaters, it is well-known to biologists as one of the most solid examples of coevolution. “One of the best activities to do with an introductory biology class is to pass around Fig Newtons, let them take a bite and then tell them the story of the fig wasp life cycle,” said tropical plant ecologist Greg Goldsmith as we recently hiked through a cloud forest in Monteverde, Costa Rica. “It’s a fascinating story.” After learning the story of the fig and its wasp, the most common question is, “Do we eat wasps when we eat figs?” The short answer is that it depends—that is, some figs are parthenocarpic, meaning they are...

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Animal-made art, medicine and language

An impressive work of wasp art is discovered in an ordinary attic, lizards that use venom to lower the blood pressure of prey could contribute to new medications, researchers translate prairie dog alarms and discover a language, contestants submit ideas for bridges designed to prevent wildlife from becoming roadkill and street art in China raises awareness of wooden chopstick waste. Here are stories in ecology and the environment from the end of January 2011. Intricate wasp nest design: Some wasps create nests by creating a paper-pulp-like material from saliva and wood fibers. The colorful nest pictured above was discovered by a plumber in an attic in the United Kingdom. Luckily for the photographer and the plumber, the wasps that created this massive nest had already abandoned their home by the time it was found.  Read more or visit the original photo stream on Flickr. Medicine from lizard venom: By surveying two dozen species of anguimorphs, researchers have found that some lizards previously thought to be nonvenomous actually are able to administer toxins. The results—published in the journal Molecular and Cellular Proteomics—provide insight into the venom delivery mechanisms of lizards. In addition, the researchers suggest the potential for developing new blood pressure medications. That is, peptides in the lizards’ venom immobilize prey by lowering its blood pressure. Read more at “Researchers take lizard venom to heart.” Prairie dog language: A recent National Public Radio (NPR) article, describes the work of Con Slobodchikoff of Northern Arizona University, who has been studying the warning calls of prairie dogs for 30 years. Using computer programs to analyze sounds, Slobodchikoff and colleagues have found that these social rodents have more than just a couple of alarms—they seem to have an entire language. At one point, the researchers recorded prairie dog responses to four humans dressed exactly the same except for the color of their shirts. As Slobodchikoff explained in the NPR article, “Essentially they were saying, ‘Here comes the tall human in the blue,’ versus, ‘Here comes the short human in the yellow.'” Read more and hear the calls at “New Language Discovered: Prairiedogese.” Wildlife crossing: Architects and designers submitted entries to the International Wildlife Crossing Infrastructure Design Competition to develop the most effective structure to transport wildlife across highways. The goal of the competition was to create bridges, tunnels and other paths that would encourage wildlife to safely traverse roads, thereby reducing incidents of vehicle collisions with wild animals. As described by The New York Times, the winning “bridge is broad enough to allow for strips–lanes, actually–that resemble forests, shrubs and meadows, with the aim of satisfying the tastes of any of the...

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From the Community: Parasitic wasps, flamingo pigment and spiny anteaters

Altered behavior in caterpillars carrying wasp eggs, preliminary thoughts on the 2010 election results, monitoring climate change from Mount Everest to Baffin Bay, insight into drug-resistant bacteria mutations and origins of the Black Death. Here is the latest in ecological science for the first week in November.

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Field Talk: Uniformity and diversity in the Homogecene era

Imagine a small town where everything is uniform—a tiny community of individuals who eat the same meals and pair up with people with similar qualities and traits. The scenery is stripped down: one church, one pub and cookie-cutter houses. Now add in social interactions. Greetings occur but they have few variations; life is routine. And just a few miles over in a town with the same layout, similar individuals are interacting, eating and greeting, in all the same ways.

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Smell, not sight, guides fly and wasp flower selection (or why stinky flowers attract flies)

Picture this: a luscious green mountain range littered off and on with flowers of every type. Lower in the mountains is green vegetation, higher up are grasslands. Eucomis, or pineapple lilies, have a striking, colorful appearance and grow at varying altitudes along the mountainside. But there tends to be one surpising difference: Two species of the higher altitude pineapple lilies have, not the delicate scent of coconut as do some of the other species, but the much more alarming scent of carrion.

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