Cone snails of the genus Conus, including the South Pacific C. geographus, can inject a potent neurotoxin (called conotoxin) that belongs to a class of poisons called calcium channel blockers. These toxins inhibit the flow of calcium ions into cardiac (heart) and smooth muscle cells. A sufficient inflow of calcium ions is necessary for contraction of the heart muscle. Muscle contraction involves the reaction of actin and myosin microfilaments which slide over each other. Calcium is essential for the phosphorylation of myosin; an insufficient uptake of calcium ions can result in cardiac arrest. As a medical treatment, calcium channel blockers are used to lower blood pressure, relieve painful angina, and to stabilize abnormal (irregular) heart rhythms.

Although there is some disagreement among authorities, sexual encounters between praying mantids often result in a horrifying experience for the hapless male. Praying mantids are well-adapted for capturing and demolishing prey with strong, grasping (raptorial) forelegs, powerful jaws (mandibles), and a triangular head and large eyes resembling an alien creature from "The X-Files." Mantids spend all summer preying upon all sorts of insects and spiders, periodically molting their exoskeleton and enlarging their bodies. After about two weeks following his final molt, the male mantis reaches sexual maturity and begins to seek out a female. Like other males (including humans) he is driven by genetic programming and an irresistible scent secreted by the female. [Human males are also driven by high levels of testosterone, often not thinking with the head on their shoulders.] Experimenting with European mantids, K.D. Roeder of Tufts University in Medford, Massachusetts, has made some startling observations on the brutal sexual behavior of these remarkable insects. Since the male is smaller than the female, he can be overpowered by her rather easily. Therefore, he must approach her very cautiously and slowly, preferably while she is busy grooming herself or catching and feeding upon another insect victim. If he approaches her carelessly (like in a Peter Sellers comedy), he very likely will never live to pass on his genes. If his approach is successful he mounts her back, tightly clasping her with his forelegs and penetrating her ovipositor with his penis apparatus. [The explicit, x-rated details of this act is beyond the scope of this article and may result in the expulsion of WAYNE'S WORD from the Palomar College web site.] Occasionally the female is not receptive to the male's advances, and quickly turns on him--biting off his head. Curiously enough, a reflex mechanism in the male allows him to complete the mating process without his head. [Mindless mating without using one's "thinking head" is also a common phenomenon in many human males.]

After mating, the intact male (assuming that he didn't lose his head) often shows little or no inclination to escape from his savage mate. Although some males do escape unscathed, many are seized by the female and are dismantled and eaten organ-by-organ, often head first. Serving as a "last supper," the sacrificial male provides his mate with a meal in late autumn when insect food supplies may be scarce, and when she desperately needs vital time and energy to make several egg cases packed with hundreds of eggs. Like the black widow spider, the male mantid's sexual suicide is certainly not in vain.

Although it is difficult to top the sexual suicide behavior of male redback spiders and mantids, another remarkable example of this male self-destruction and cannibalism is worth mentioning. It concerns female fireflies of the genus Photuris, members of the beetle family Lampyridae. Like other members of this large beetle family, they have bioluminsecent organs at the tip of their abdomen which they use to attract members of the opposite sex. Different species can identify their own kind in the darkness of night by the peculiar flash pattern for their species, which is based on the length of the flashes and the precise time interval between flashes. The animal behaviorist James Lloyd (Science Vol. 149, 1965) described the female photuris beetle as the ultimate "femme fatale" of the insect world. She uses the light at the tip of her abdomen to signal males of her own species and to mimic the flash patterns of unsuspecting males in the related genus Photinus. Attracted by her seductive blinking lights that mimic their own females, the photinus males attempt to mate with her, but soon become victims of lust as their bodies are devoured by the cannibalistic photuris female. In the following example, the hapless male is not eaten by his mate, but nonetheless his lust and copulatory behavior will cost him his life.

The plight of the male honey bee is one of the classic examples of sexual suicide. This incredible story is actually very complex and is eloquently explained by Mark Winston in his fascinating book The Biology of the Honey Bee (Harvard University Press, 1987). Honey bees are social insects that live in complex colonies. They have a division of labor with a true caste system in which different bees assume various roles within the colony. In fact, the way that all the thousands of individuals selflessly serve the collective is somewhat reminiscent of "The Borg" in Star Trek: The Next Generation. Compared with the smaller diploid female workers, the haploid drones have a relatively easy life--until that fateful day when they must fly into the sky for their rendezvous with a sexually receptive queen. The entire sex act takes place during flight, like a jet fighter refueling in mid air. Only in the case of honey bees, the actual bridge between the drone and the queen is his extended penis apparatus (endophallus) which is tightly plugged into the sting chamber of the receptive female. His explosive ejaculation ruptures his everted penis apparatus and propels semen into the queen's oviduct. In addition to the forceful ejaculation of semen, the terminal bulb at the tip of the everted endophallus remains in the queens vagina, and according to Mark Winston (1987), this "plug" may function to prevent semen from flowing out of the vagina following copulation. [So there is truth in the old tale about the drone's penis breaking off inside the female.] In the sci-fi film "Zzzzz" (a TV episode from the 1964 Outer Limits series), a queen bee metamorphosed into a women named Regina. In this "B" rated-film, Regina wanted to mate with the entomologist Ben Fields to produce a super race of bees. It is now very clear why the terrified entomologist/bee keeper did not want to have sex with this queen bee lady. Getting back to the world of real honey bees, the drone bee dies within minutes after his violent eruption of semen and literally falls from the sky, occasionally landing in a Palomar College parking lot. Please refer back to paragraph 1 of Introduction.

With her sperm receptacle (called a spermatheca) filled, the queen can lay fertilized, diploid eggs (which become females) and unfertilized (haploid) eggs (which become males) in the hexagonal wax cells of her hive, in one of nature's truly amazing insect cycles. In case you are wondering, worker bees build unfertilized hexagonal cells a little larger in order to accommodate the drone. When full, the queen's spermatheca may contain more than five million sperm, more than enough to lay 1500 fertilized eggs daily during the summer, and up to 200,000 fertilized eggs annually during her life span of nearly four years. According to Mark Winston (1987), the queen may get a complete fill-up of sperm on one mating flight (often from more than one male), or she may make several flights over a period of several days to a week. And during the mating flight of one queen, up to 17 male drones may commit sexual suicide.

In a PBS TV broadcast about honey bees, the narrator referred to drone bees as "clones" of each other. Since clones are usually defined as genetically identical individuals (usually derived asexually), WAYNE'S WORD strongly disagrees with the accuracy of this broadcast. Although the haploid drone comes from an unfertilized egg with only one set of chromosomes, they are certainly not all genetically identical. The diploid queen bee undergoes normal meiosis (oögenesis) producing haploid eggs. During this cell division process her 16 pairs of homologous chromosomes become altered and reshuffled through crossing over and random assortment, resulting in haploid eggs that are not chromosomally identical. In fact, with 16 pairs of homologous chromosomes, there are 65,536 different chromosomal combinations possible. Furthermore, the additional random combination of gametes during fertilization also insures that worker bees are not chromosomally identical. One more gee whiz comment about honey bees. Since the foraging bees bring nectar back to the hive in special stomachs (where it is converted into honey and regurgitated into wax cells of their hive), honey is truly analogous to bee vomit.

• Roig-Alsina, A. 1993. "The Evolution of the Apoid Endothallus, Its Phylogenetic Implications, and Functional Significance of the Genital Capsule (Hymenoptera, Apoidea)." Bolletino di Zoologia 60: 169-183.

  See: Bee Careful Of The Killer Bees

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  B. Male Gender Inequity And Exploitation

  Although many males do not die directly from sexual intercourse and they are not actually eaten by their female lover, they have a very limited life in time and space. In some species the males are anatomically reduced to nothing more than a sperm-producing reproductive machine incapable of doing much more than inseminating the female.

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  4. Mysterious Males Of The Deep-Sea Angler Fish

  The most amazing and bizarre examples of the total reduction in the role of males are the deep sea angler fishes (including Borophryne, Lophius, and Ceratius of the Order Pediculati) living in the pitch-dark depths of the ocean. These incredible fish may live at depths reaching 200 to 600 fathoms (1200 to 3600 feet), or more. Because life is so sparse at these vast depths of the ocean, the angler fish must be well-adapted to capture the limited supply of prey that happen to swim its way. Some angler fish appear absolutely fierce (rivaling any T-Rex or velociraptor in facial appearance) with a huge mouth and long, needle-like teeth that instantly trap any animal that swims within range. Some species also have a slender, antenna-like projection extending above and in front of the massive mouths. The tip of this "fishing rod" device is bioluminescent (glowing in the dark), and attracts curious fish living in these vast regions of oceanic darkness to the ominous jaws of the angler fish. Angler fishes and other amazing deep sea creatures are discussed in a fascinating book by C. P. Idyll (Abyss: The Deep Sea and the Creatures That Live In It, Thomas Y. Crowell Company, 1976).

  Because angler fish are so sparsely populated throughout the vast millions of cubic miles of ocean, chance mating encounters between males and females would be unlikely. In fact, when deep-sea anglers were first brought up in trawls they puzzled scientists because they were all females. Then someone noticed small "growths" on the female that turned out to be males. When a tiny male meets a female he bits into her flesh and literally fuses with her body. Like the linking together of web sites on the Internet, the two blood supplies also fuse together so that the male obtains nutrients and oxygen from the female. Without any need for most of his organ systems, such as eyes and digestive organs, the male's body degenerates into essentially a pair of sperm-producing testicles. Thus the female essentially becomes a hermaphrodite with up to six or more of these tiny male parasites attached to various parts of her body. Although functionally bisexual, the eggs and sperm come from genetically distinct parents, thus providing vital genetic variability through meiosis and genetic recombination. As a functional hermaphrodite she can have sex any time or place, without worrying about meeting a male in the dark abyss of the ocean. Clinging to her body like minute, blood-sucking parasites, the males have little interaction with the female, except to fertilize her eggs with sperm. This fascinating story (and many others) are nicely explained in a pictorial book entitled The Mating Game by Robert Burton (Crown Publishers, New York, 1976).

  

  A female deep-sea angler fish (Linophryne macrodon) with a stalked, luminous bait (above her huge jaws) and a strange barbel appendage on her under jaw. She also carries a minute, blood-sucking, parasitic male attached to her lower side. [Illustration by graphic artist Elaine M. Collins.]

  Although it is difficult to top the male gender exploitation of deep-sea angler fish, a microbiologist colleague informed WAYNE'S WORD of another bizarre example of the ultimate in male reduction and gender inequity. It is a minute male nematode worm that lives its entire adult life within the reproductive tract of its female host mate. The following example will conclude this essay on male gender inequity. It concerns the fig/fig wasp story, one of the most remarkable examples of coevolution between a plant and an insect.

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  5. The Incredible Fig/Fig Wasp Scenario

  Certainly one of the most complicated and remarkable examples of male gender inequity is the classic disproportionate role of the male in the fig wasp life cycle. In fact, this subject is so fascinating that the staff at WAYNE'S WORD has mentioned it in several other articles.

  Go To Calimyrna Fig And Its Wasp See: Role of Figs in the World's Religions See: Plant Sexuality And Political Correctness See: The Gall Controversy Involving The Fig Wasp

  NYBG Steere Herbarium Definition of Gynodioecious: Sexual condition of a species that bears pistillate flowers on some plants and bisexual flowers or staminate flowers as well as pistillate flowers on other plants. The important word here is "or" rather than "and" [e.g. Fig (Ficus) & Mulberry (Morus)].

  Tiny male and female fig wasps are borne inside hollow, fleshy, flower-bearing structures called syconia. [The syconium is what most people associate with the tasty fruit of a fig, but technically it is not a true fruit.] The syconium is lined on the inside with hundreds of tiny, pollen-bearing male flowers and seed-bearing female flowers, and the wasps develop from eggs laid inside the ovaries of the short-style female flowers (one egg per flower). In about half of the fig species (referred to as monoecious), male flowers and the long and short-style female flowers occur in the same bisexual syconium; but in all other fig species (referred to as dioecious or gynodioecious), the seed-producing, long-style female flowers only occur in unisexual syconia on female trees (with no male flowers). Since wasp eggs are not laid in the long-style flowers, the ovary of this type of flower contains a seed rather than a wasp (assuming it is pollinated). This remarkable floral dimorphism is how the fig tree produces seeds while still maintaining its vital, "in-house" population of symbiotic wasps. There are approximately 1,000 species of figs (genus Ficus), mostly distributed throughout tropical regions of the world, and they all have their own pollinator wasp species that only enters their syconia through a small opening (called an ostiole) to pollinate the female flowers inside. Without their special symbiotic wasps transferring pollen from one syconium to another, the female flowers inside would not get pollinated and no seeds would be produced (a catastrophe for the fig tree).

  It should be noted here that some fig species have two species of symbiotic wasp pollinators. In fact, the classic one-fig/one-wasp partnership has been challenged in an article by D. Molbo et al. (Proceedings of the National Academy of Sciences 2003 100: 5867-5872). The two fig wasp species may be closely related sister taxa, or may be quite different from each other. This indicates both long-term coexistence on shared hosts and relatively recent colonization of fig species. Fig syconia may also contain "bogus fig wasps" who do not pollinate the female flowers inside. It is clear that the fig-fig wasp scenario is far more complicated than originally described.

  Read About Bogus Non-pollinator Fig Wasps

  

  A close-up view inside of the rustyleaf fig syconium showing numerous minute male and female flowers. The female flowers are pollinated by a tiny pregnant (gravid) female fig wasp that enters the syconium through an opening at one end (the upper end in photo).

  

  Magnified view of a male and female fig wasp (Pleistodontes imperialis) next to the "eye" of an ordinary sewing needle. The smaller, wingless male has an amber body and black head with greatly reduced eyes.

  

  Close-up view of a male and female fig wasp (Pleistodontes imperialis). The smaller male (right) has a greatly reduced body which has two primary purposes: (1) Inseminating the female and (2) Drilling exit tunnels through the syconium wall.

  See Straight Pin & Sewing Needle Used In Wayne's Word Articles

  

  Magnified view inside syconium of Ficus rubiginosa showing two male and two female fig wasps (Pleistodontes imperialis). The smaller males (left) have a black head and amber-colored, wingless body. The winged females (right) are larger with longer antennae. In this image, the inseminated females have imerged from their individual flowers and are ready to escape from the syconium.

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  Richard Dawkin's Model Of Vicarious Selection

  Chapter 10 of Climbing Mount Improbable, W.W. Norton & Company, 1996.

  The staff at WAYNE'S WORD agrees with Richard Dawkins that the fig/fig wasp scenario is truly one of the most remarkable and complicated examples of coevolution between a plant and an insect; however, his fascinating discussion of vicarious selection to explain this symbiotic relationship is based on dioecious figs with separate male and female trees. About half of the world's fig species are monoecious (with male and female flowers in the same syconium) and do not fit Dawkin's model for vicarious selection. Dawkin's model is based on the paper by Grafen and Godfray (Proc. R. Soc. Lond. 245, 1991). Vicarious refers to an act performed by one person or organism (in this case a syconium) in place of another.

  According to Carole Kerdelhue and Jean-Yves Rasplus (Oikos Vol. 77: 163-166, 1996), dioecious figs may have evolved from monoecious ancestral fig species due to selection pressure by non-pollinator fig wasps. Although these non-pollinator wasps belong to the same order Chalcidoidea as pollinators, many of them belong to different families. They do not benefit the fig and may even be harmful, especially when they compete with and/or parasitize the beneficial pollinator wasps. According to Kerdelhue and Rasplus (1996), non-pollinator, parasitic wasps never occur in the long-style flowers of female syconia on female trees, and non-pollinator gall-makers are uncommon in the male syconia of male trees. Therefore, seed production in female syconia and pollinator wasp production in male syconia are not diminished as in the syconia of monoecious figs with stratified ovaries containing all of the non-pollinator wasp species. In addition, no gall-makers that lay eggs through the syconium wall (after pollination by pollinator wasps) have ever been found so far in dioecious figs. These bogus fig wasps have very long ovipositors that can penetrate the entire outer wall of the syconium. For the fig, having separate male and female trees (bearing male or female syconia) in the population may have a distinct adaptive advantage with regard to pollination and seed production.

  Bogus fig wasps (family Torymidae and Eurytomidae) have an unusually long ovipositor. It can easily penetrate the long-style flowers which are too long for true female fig wasps. In fact, some species can penetrate the entire syconium from the outside! Thus, bogus fig wasps can lay eggs in long-style fig flowers reserved for fig seeds. Consequently, no seeds are produced in these flowers. In addition, the bogus fig wasps do not pollinate fig flowers. Although they do not benefit the fig tree, torymid and eurytomid wasps are common inhabitants of New World monoecious fig syconia. Their coexistence with natural fig pollinator wasps is a complex and perplexing coevolutionary problem in fig biology.

  

  A. Short-style female flowers inside male syconium of a dioecious fig. [Male flowers also occur in this syconium.] B. Long-style female flowers inside the female syconium of a dioecious fig. These syconia do not have the intermediate ovary positions of monoecious figs (see below), and they do not harbor all the non-pollinator wasp species of monoecious figs.

  In Dawkin's model, selection for wasp pollination morphology (i.e. ovipositor length, etc.) and behavior (purposive loading and unloading of pollen) is taking place in wasps who enter and leave male syconia (containing short-style female flowers) on male trees. This selection is crucial for the perpetuation of fig trees when wasps enter female syconia on female trees (which superficially resemble male syconia). Female syconia produce seeds (the vital genetic link for fig trees) and are a genetic graveyard for wasps because they cannot oviposit in the long-style female flowers. For wasps in female syconia, mutations for a longer ovipositor that could reach the ovary of long-style flowers would not be passed on. For wasps in male syconia, there is no selective advantage for longer ovipositors because they are already long enough to easily penetrate the ovary of short-style flowers.

  Some varieties of the common dioecious fig (F. carica), such as the delicious Calimyrna, have another method of blocking the development of non-pollinator bogus fig wasps. Without pollination, Calimyrna syconia fail to ripen and drop from the branches. This eliminates the life cycle of non-pollinator fig wasps that may have laid eggs in the syconium.

  Although vicarious selection for ovipositor length may be dictated by the male syconia on male trees, there are several other pollination patterns in dioecious figs that differ from Dawkin's model for vicarious selection. See Pollination Patterns In Dioecious Figs. Dawkin's dioecious fig model fits species of dioecious figs in the subgenus Urostigma. These figs have the prerquisites for vicarious selection, including: (1) purposive pollination (pollen collecting and pollen transfer by female wasps); (2) female wasps with pollen baskets (corbiculae); (3) exit tunnels cut by male wasps, etc. But in reality, there are many fig species with passive pollination (i.e. not deliberate), without pollen baskets, and without exit tunnels cut by male wasps. In fact, it is doubtful that vicarious selection adequately explains the remarkable evolution of the numerous fig species with pollination patterns that are different from Dawkin's fig model.

  Monoecious syconia of Ficus sur contain long-style and short-style female flowers densely packed together in a layer that lines the inner cavity of the syconium. Although the styles all form a relatively continuous stigmatic layer called a synstigma (i.e. all stigmas in the same plane) within the syconium, the ovaries may be deep or shallow relative to the synstigma depending on the length of their flower stalks (pedicels). Generally, the deep-seated ovaries (on short pedicels) with long styles each contain a seed, while the shallow ovaries (on long pedicels) with short styles each contain a wasp larva (referred to as a "gall flower" by some authors). A pollinator wasp walking on this "bed" of styles (synstigma) can insert her ovipositor down the short style and easily penetrate the ovary where she lays an egg. The deep-seated, long-style ovaries are out of reach for her ovipositor (style longer than her ovipositor), and consequently these ovaries develop seeds rather than wasp larvae.

  Because of intermediate style lengths (between long and short) and different ovary heights due to the length of flower stalks (pedicels), the ovary position of female flowers in monoecious fig syconia often forms a stratification. According to Kerdelhue and Rasplus (1996), there are at least 4 different ovary layers occupied by beneficial (pollinator) and non-beneficial and/or harmful non-pollinator wasps. These layers are listed according to their position (depth) from the stigmatic surface (synstigma) within the syconial cavity. See the following illustration.

  

  Heterostyly and four ovary layers (stratification) within the syconium of a monoecious fig (Ficus sur). (1) Yellow: The most shallow ovaries (near surface) with shortest styles which typically contain a pollinator wasp larva; (2) Green and (3) Red: Slightly deeper ovaries that typically contain non-pollinator wasp larvae; (4) Black: The deepest ovaries with longest styles that typically bear mature seeds. 1. The shallow ovary layer of short-style flowers (yellow ovaries in above illustration) are mostly occupied by larvae of wasps that oviposit from the synstigma within the syconium cavity, including Ceratosolen (pollinator) and Sycophaga (non-pollinator gall-maker), and by their parasitic wasp larvae (parasitoids or inquilines). 2. A second slighter deeper ovary layer (green ovaries in above illustration) includes the wasps of layer 1 (above) plus some additional gall-makers which lay eggs from the outside (Apocryptophagus). 3. A third deeper ovary layer (red ovaries in above illustration)) produces a few seeds and provides shelter and food (galled endosperm tissue) for mainly Apocryptophagus and a few Sycophaga individuals. 4. A fourth, deepest ovary layer (black ovaries in above illustration) produces mostly seeds and some wasps, including some Sycophaga and a few Apocryptophagus. If the non-pollinating wasps are very numerous, the medium layers 1 and 2 (yellow and green ovaries) will be occupied entirely by exploiters and these occupied flowers will not produce seeds or pollinator wasps. According to Kerdelhue and Rasplus (1996), this probably represents a high cost to the fig with regard to seed production.

  See Pollination Patterns In Dioecious Figs See More Articles About Fig Wasp Symbiosis Another Problem In "Climbing Mount Improbable"

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  The following scenario occurs three or more times a year (depending on the fig species). The example used in this discussion is essentially based on the monoecious Australian rustyleaf fig (Ficus rubiginosa) and its symbiotic pollinator wasp (Pleistodontes imperialis). About three months after the wasp eggs are laid inside short-style flowers by the mother wasp, the mature male wasps emerge first--each male chewing his way out of the ovary he was borne in. Compared to the larger winged female (another example of sexual dimorphism) he is a minute, wingless wasp with greatly reduced eyes and a reduced, feeble body. In fact, he can barely walk, clumsily moving around inside the syconium in search of a female. Actually he really doesn't need wings, running legs or eyes because his short adult life on this earth is totally within the confines of his dark and dingy syconium. For his reduced size, he does have strong little mandibles (jaws) which come in very handy in the two major roles of his short life cycle:

  Male Role #1.

  He crawls to a short-style female flower that contains a mature female wasp. He climbs up on the ovary of the flower, bites a fertilization hole in the ovary wall, and inserts his long, slender rear end (abdomen) into the opening (and into the wasp's vagina), thus inseminating a female who really never sees who is mating with her. Each male repeats this process with every female they find, as they slowly move through the dense "jungle" of long and short-style female flowers. After being inseminated the female crawls out of the fertilization hole through the ovary wall initially made by the male. At this precise time the male flowers have reached maturity and are shedding pollen. The female wasp purposively (deliberately) collects pollen from the male flowers and packs it into a pair of little pollen baskets (corbiculae) on the underside of her thorax. In many fig species (especially dioecious figs) she simply collects pollen passively (not deliberately) in the folds and crevices of her exoskeleton as she moves through dense, pollen-laden male flowers. It is difficult to generalize about pollen-collecting behavior because it varies considerably within the incredibly complex subgenera of Ficus.

  

  A male fig wasp (Blastophaga psenes) mounting a short-style female flower and inserting his long, slender abdomen into a fertilization hole that he cut through the ovary wall to inseminate the female fig wasp inside.

  

  A female fig wasp (Pleistodontes imperialis) emerging from a short-style female flower. She enlarges and pushes through the fertilization hole in the ovary wall cut by the male.

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  Male Role #2.

  At this time the male wasps begin tunnelling through the syconium wall, chewing away at the tough outer layer. These exit tunnels are absolutely crucial in order for the female wasp to escape. Again, the exact method of wasp exodus depends on the subgenus of Ficus. In some species, the ostiole where the original mother wasp entered to lay her eggs months earlier, actually opens again, thus allowing the pregnant (gravid) female wasps to escape. Here is one of several examples given by Richard Dawkins in Climbing Mount Improbable page 309 (1st paragraph) that just doesn't fit: "A male that did sit back and let his colleagues make the hole would be able to save up all his energy for mating with females, secure in the knowledge that he need not hold himself back for the effort of making the hole." In every fig species we have studied (either from direct observations of live wasps or from the literature), the males mate with the females before the tunnels are cut. In fact, according to Dr. J. Galil, the famous fig biologist at Tel Aviv University (Endeavour Vol. 1, 1977), all the respiratory activity of male wasps (during mating and tunnelling) increases the carbon dioxide concentration within the syconium (up to 10 percent or three times the atmospheric level in Ficus religiosa). Upon completion of the exit tunnels, the carbon dioxide level drops rapidly as the gas escapes into the outside atmosphere. The depletion of carbon dioxide activates the female wasps, causing them to enlarge the fertilization holes and push through the ovary walls of the individual short-style flowers they were born in. And of course there are many fig species that do not even have (or need) exit tunnels cut by males, the females simply exit through the main ostiole at the end of the syconium. In these latter species, the feeble males have essentially only one primary role (see role #1 above), that is, to inseminate the female.

  

  Circular exit tunnels in the mature syconium wall of the rustyleaf fig (Ficus rubiginosa). The tunnels were cut by the male fig wasps to enable the winged females to escape. Soon after the tunnels are cut, the tiny males die, their purpose in life having been fulfilled. Without the exit holes, the females would perish inside the syconium, along with their male sex partners and liberators.

  The exiting female wasps emerge from the neat circular tunnels cut by the males and fly off to other receptive syconia to lay their eggs, and the whole cycle starts all over again. With their purpose fulfilled, the tiny males soon die within the syconium, never leaving the place of their birth and sexual orgy. At this stage the syconium becomes juicy and sweet, and may serve as food for hungry monkeys and bats high in the rain forest canopy. This final phase is also important for the fig tree because it insures that seeds contained inside long-style flowers are deposited to other places (due to the purgative effect on the animals digestive tract). Many of these amazing tropical figs start growing as epiphytic vines on the host tree's limbs, soon reaching the ground where they develop extensive root systems. Like a botanical boa constrictor, these "strangler figs" eventually envelop the host tree as their tangled masses of snake-like vines fuse (anastomose) into a massive trunk.

  Although a number of testosterone-laden, male general biology students have said (jokingly) that they envied the male fig wasp, his short wasp life is basically limited to a brief sexual orgy within the stuffy syconium (with the exception of those figs that require exit tunnels through the syconium wall). But even though his role may seem limited and seemingly insignificant, the tiny male fig wasp is absolutely essential for the perpetuation of fig wasps and fig trees in one of nature's most successful symbiotic relationships.

  This article has painted a rather bleak picture for the fate and life role of males. Actually, there are many species in which the female's role after mating is also rather dismal. This is particularly true in many species of insects where the female dies soon after laying her eggs. For example, when a female fig wasp enters a receptive syconium to lay her eggs, her fate is irreversibly determined. She will never leave this hollow prison lined on the inside with tiny unisexual flowers. [According to M. Gibernau, et al. (Journal of Biogeography Vol. 23: 425-432, 1996, female wasps do in fact exit from the syconia of F. carica, F. aurea & F. microcarpa, and females can oviposit successively in two different figs of F. carica]. After she has oviposited inside the ovary of each short-style flower she will die, and the ostiole through which she entered the syconium will close. The tightly sealed ostiole prevents small ants and other minute opportunistic insects from invading the syconium for food. Females who do not become trapped in a syconial prison do not fare much better. They are easy prey for predatory insects and spiders, and are still genetically programmed to die within days or weeks, although not much is really known about these syconial outsiders.

  Other Links To Articles About The Fig & Its Symbiotic Wasp

  

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