Answer Man

Insects do need air and water

Ants are known to take a little sip now and then.
Ants are known to take a little sip now and then.

Q: Do insects need air and water? Presuming they do, how do they get it without lungs or a digestive system like ours? Osmosis?

Joe Turner, of Belleville

A: Because of their size, they obviously need only a teensy-tiny fraction of the air and liquid we humans require. Still, if insects could be kept from breathing and drinking entirely, we could save a whole lot of money on Raid, Off! and roach motels.

It’s just that insects usually go about it in an entirely different way. Take breathing, for example. Humans draw air through the nose or mouth into the lungs. There, the oxygen makes its way into the bloodstream and circulates throughout the body while carbon dioxide is expelled as waste. It’s an active process — as any parent whose little kid has ever threatened to hold his breath until he turns blue knows.

For most insects, it’s usually a much more passive system — sort of like opening the windows to air out your house. Instead of lungs, insects have a series of tiny pores in their abdomens called spiracles. These spiracles are the openings to tubes known as tracheae, which extend into an insect’s body through ever-smaller branches. These tinier and tinier air pipes finally end at an extremely small, fluid-filled dead end called a tracheole. So, air constantly enters through the spiracle, goes down the tracheae and ends up in the tracheole before making its way through the tracheole wall and into the insect’s cells. In return, carbon dioxide heads the opposite way and is expelled through the spiracles.

For most insects, it’s all done through a passive process known as “diffusion.” Since diffusion works best over only small distances, it’s one major reason we don’t have the giant ants from the sci-fi movie “Them!” populating the Earth because air would be unable to make it that far into a giant insect’s body through diffusion. It’s also why some people say they spray plants with substances like castor oil, because the oil may plug up the spiracles to such an extent that it prevents diffusion, thus suffocating the pest.

Some larger insects, however, apparently can use their abdominal muscles to help force air in and out of this tracheal system. One final fun fact: According to the National Pest Management Association, cockroaches can survive 30 or 40 minutes without breathing, even when held under water.

The subject of insect drinking is even more fascinating because there’s such a wide range of methods. Often, it depends on their diets. Insects that feed on plants can take in most or even all of the liquid they need from the water content in the vegetation they eat. Entomologists, for example, note that tropical stick insects, which live in a damp environment anyway, do not have the physical apparatus to drink as we know it so they draw all of the liquid they need through their diet.

However, experts say, it is not unusual for even carnivorous insects to drink from morning dew, raindrops, fruit or the surface or edges of puddles and ponds. (Remember, they don’t need much.) I’ve never tried this, but they say if you put out a damp tissue on a hot day, you may see an insect happy hour develop.

If you had a small magnifying glass, you’d also see them drinking in different ways. Flies, for example, suck it up while some wasps may use a tiny structure that looks like a tongue. Most adult butterflies and moths use their proboscis to take in their daily requirements by sipping flower nectar, but, if desperate I suppose, can find liquid in sap flows on trees, rotting fruits or even bird droppings and animal dung. Some ants may decorate their nests with small feathers that can collect dew in the early morning. You can watch an interesting video of ants drinking at blog.wildaboutants.com/2010/07/20/do-ants-drink-water/

Spiders also require water daily, which is why those kept in captivity should have ready access to a damp sponge or small cap or dish of water, depending on their size. In the wild, they’re perfectly satisfied with the dew or raindrops on vegetation. However, some must go to extremes. In the desert, the whistling spider, an Australian tarantula that can produce a hissing sound when provoked, covers its burrow with a thin layer of web to both keep it humid and capture any dew or raindrops. Pseudoscorpions may use their pincers to take water from their webs and put it in their mouths while some spiders may actually eat their damp webs in the morning.

Of course, if you want a truly strange creature, look no further than the common pillbug, which is, admittedly, a crustacean and not a true insect. But according to longtime naturalist and teacher Debbie Hadley, the pillbug breathes through gills and does not urinate, passing off ammonia gas through its exoskeleton when it needs to. And while it can drink through its mouth, it also can take in liquid through its rear end, which is equipped with tube-shaped structures called uropods to wick up water.

Q: I know that Illinois currently hands out out IOUs if you win a large prize in the state lottery because of the ongoing budget impasse. But if I win a multistate lottery — say, the Mega Millions — would I have to wait, too, even though it’s offered in 44 states, D.C. and the Virgin Islands?

F.A., of Cahokia

A: Unfortunately, yes, all of your dreams of yachts, mansions and around-the-world cruises would have to be put on hold. According to Illinois Lottery spokesman Steve Rossi, the state in which the winning ticket is sold is also responsible for paying out the prize. So at the moment, all you’ll get for any prize more than $600 will be a promise you’ll be paid whenever the governor and Legislature can agree on a spending plan. Currently, it looks as though you’d better hold onto your day job for a good, long while.

Today’s trivia

For whom is the popular analgesic heat rub Bengay named?

Answer to Wednesday’s trivia: After actress Carole Lombard was killed in a plane crash on Mount Potosi, Nev., on Jan. 16, 1942, she was widely honored as the first United States woman killed in the line of duty during World War II. After Japan’s attack on Pearl Harbor just two months before, this star of screwball comedies turned serious and went out to help sell $2 million in U.S. War Bonds. She was returning from appearing at a bond drive when her plane crashed. She was 33 and married to Clark Gable at the time. When Gable died in 1960, he was buried next to Lombard, the third of his five wives.

Roger Schlueter: 618-239-2465, @RogerAnswer

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