National Geographic : 1966 Dec
the mantis isn't really an insect, but a flower come to life (page 853A).* Not all predators at the insect crossroads travel there to eat. Some have a more bizarre purpose: to find a host for their young. The conopid fly, for example, waits on a flower until a sand wasp comes along. Then it chases the wasp, catches it, and with a specially adapted egg-laying organ forces apart the segments of the wasp's abdomen to deposit an egg inside. The egg hatches, and the larva begins to eat its host. Eventually the wasp flies to its burrow in the sand and dies. The larva winters in the wasp's dry abdomen, then transforms into a pupa. Fly Digs With Inflatable Head Spring comes, and with it, a final wonder of the conopid's life. The adult punches its way out of its shroud and up through the sand to the surface, using a strange inflatable organ. Like a balloon, the organ swells out from a slit in the conopid's head and presses back the sand. As the bubble alternately in- TEAR OUT THE ATTACHED PAGE ) and plan your voyage, via television, to the hidden world of insects. flates and deflates, the fly wriggles upward. Perhaps the most intriguing example of insect parasitism unfolds in the story of a species of Stylops, one of the twisted-wing beetles. That tale took 20 years of study to piece together, for the male has a lifetime of only a few hours as a mature insect, and the female spends most of her existence hidden within the body of her host. Both stylops sexes parasitize bees of the genus Andrena. Each begins life as a grub no bigger than a minute speck of dust. Each develops in an andrena larva, and continues within the body after the larva matures into an adult bee. Andrenas that harbor male stylops die in early spring, shortly after the quarter-inch *See in NATIONAL GEOGRAPHIC: "Asian Insects in Disguise," by Edward S. Ross, September, 1965; and "Praying Mantis," by John G. Pitkin, May, 1950. 4) ct (U 5=t (I)-a O )aI *i-i (S, O <-1 (D~ Fu b<-> I x-. T3 R3 +' cnO C's .z -e 0 al I io . .0 C^ zsaU( ^^^ "v I ~,-e Y a~o ~~ 0h 13 ,o~fl0 5.' '+. (1)4 V^ Q)v 5.'0 C' rt o,i. cd NO 7.S 0 d"£ bC .0 0.0 M; C 0 -ro . 3 Sg0 0.S o oa> ^-^ ^ m"0 i- C~ 5i.' U I 0cd .> ~tNc3 -~ V 0 v r^ c5d cadI.' vy} .0 cr -e u- c ¢cd 00- J U.+' u a O.v ^. (-1 >i7 Os b " flB O C CU (U., ~..c 0 ." 0 s.' W*-0 cr S[/ K 5. ^ .' .0 - 0t .0 '..| ' ^'P0 bL0 s^^ c a < oc . , - y - o- O o0ob0 0r 5. su 0u 0 '-' SiS' 00d0 a 0 S '' io Z^vl 853 Hazardous cavern of a Dutchman's pipe claims unwitting victims. The plant lures gnats with a scent similar to that of the fungus on which they breed. Once inside, Dr. Ross theorizes, a gnat mistakes the bright stem end for an exit and makes its way there. If the insect carries pollen, fertilization triggers a process that lowers the vaselike throat, admitting light and allowing easy escape. Dead gnats probably carried no pollen or perished in a plant too immature for pollination.