I get asked quite a lot about carpenter bees. They can be quite a nuisance and destroy wood. They typically will return each year to the same location and bury their eggs inside of a “tunnel” they have created. The create this tunnel by destroying small sections of wood. Here is a DIY infographic that might help.
ALL THE INSTRUCTIONS to make an animal’s body are in each one of its individual cells. But how does an embryo know that a scrotum should be built in the groin, and not on your forehead? During fetal development, a complex dance of proteins turns genes off and on. One end of an embryo becomes a head, and the other end a butt.Sometimes things go wrong. Sometimes the regulatory genes that tell the body “head here, legs there” make spectacular mistakes. And that’s how a millipede ends up with 6 extra pairs of genitals. Or, if you count each dangly bit, a total of 16 sexual appendages; 4 normal ones and 12 extras.That mutant millipede isn’t just a freak; it can teach us a lot about how bodies are put together, and how genes are regulated.
Millipede sex was already pretty weird before the extra genitals
Mammals’ internal and external sexual gear are located in similar spots, and connected with a series of tubes. In Julid millipedes, both male and female millipede gonads (ovaries and testes) are internal, on their third ring. That’s a bit like having your ovaries on your sternum.
Female external genitals are also found on the 3rd ring, but are housed in a sealed box. The male has to push open the lid of her box to deposit his sperm. He does this with special sexual tackle called gonopods (“sex legs”). These gonopods replace his 8th and 9th pairs of legs. They aren’t penises; they are sort of a sperm-carrying strap on.
The testes are not connected to these sexy legs; and to transfer the sperm, millipedes have to…. well, go fuck themselves. Males contort and curl around to insert their gonopods into a tiny pore between their second pair of legs. The gonopods are hollow, and suction up the sperm. Now the male is ready for love.
Normal male Ommatoiulus moreleti, the species in question, have 4 sex legs. Like everything else on a millipede, they are in pairs. But even for millipedes, 16 sexual appendages is rather a lot.
Silencing of the Genes
A special class of genes have “control” functions; they are commonly known as Hox genes. They are the genes that help instruct a developing embryo about segment identity: “mouth goes here, anus goes there.” Hox genes work with other regulatory genes to tell developing cells which of all their potential DNA choices to activate. If it all works correctly, you don’t end up with hairy eyeballs.
Our well-endowed millipede is a “homeotic mutant.” Somehow, the instructions to make genitals did not get turned off, and the millipede just kept replacing its legs with sexual appendages. Sixteen of them. Did I mention there were 16 of them?
It’s Genitals all the Way Down
To add even more complexity into the story, when millipedes hatch out of their eggs, they do not have functional gonads or sexual appendages. They have their first three pairs of legs, and no more. As millipedes grow and shed their exoskeletons, they add “diplosegments” with two sets of legs on each ring. Eventually, around the 4th or 5th time they shed, their genitals appear.
Even stranger? Male millipedes of some species are able to reverse puberty. Adult males with functional gonopods can actually revert back to their pre-sexual appendage stage with a molt.
Programming for the location and construction of future genitals is set early in embryo development. In the diagram below, the authors suggested a mechanism for how extra genitals might arise in a young millipede. The black circles represent cell groups destined for future genital building; the grey circles are regular segments.
The monster’s extra genitals were displaced by exactly 16 units, which could be produced by 4 cycles of splitting in an embryonic primary segment:
There is a long history of mutants in millipedes; we just haven’t had genetic tools to document what’s going on genetically until fairly recently. Researchers are just beginning to pick apart millipede genetics; for most millipedes, we don’t know much about their genomes. Some very exciting discoveries await.
Drago et al. 2008. Non-systemic metamorphosis in male millipede appendages: long delayed, reversible effect of an early localized positional marker? Frontiers in Zoology 2008, 5:5. doi:10.1186/1742-9994-5-5
Akkari et al. 2014. Segmentation of the millipede trunk as suggested by a homeotic mutant with six extra pairs of gonopods. Frontiers in Zoology 2014, 11:6. doi:10.1186/1742-9994-11-6
Big thanks to researcher Derek Hennen for advice on millipedes; he also pointed out this particular species of millipede has caused train derailments. Not with their genitals, though.
? TMI ? just thought you would find this article interesting.
This Bug Has Heard All Your Jokes About Its Head Already
THIS MALE LACEWING looks like he’s wearing a dildo as a festive party hat. It’s not a sexual organ, but it is involved in sex.
It’s a glenofinger. That’s not an obscure Bond villain, but an inflatable “come hither” signal to females. The bulging gland gets bigger when the male is interested in a hookup. How does it work? “Well, we’re not completely sure,” said Dr. Shaun Winterton, Senior Insect Biosystematist for the California Department of Food & Agriculture. He was working on a “very ho-hum new description” of a lacewing from Australia when he noticed something interesting: two preserved male specimens had a strange dimple on their neck—a glenofinger.
Dr. Peter Duelli first described this odd structure in 2004, when he observed males slowly erecting their glenofinger—but they were very shy. “When the males are undisturbed, the glenofinger can grow to almost the size of the abdomen. At the slightest disturbance (vibration, noise, shadow) it’s withdrawn.” Winterton commented, “They’re very secretive about it. You really have to set the mood for this sort of thing to happen.”
Winterton’s not sure if the glenofinger inflates with air, or fills with body fluid. “We know only the males of the genus Glenochrysa have these glands,” he says. “A good analogy would be the pockets of your jeans, it’s tucked away like a pocket.” In other words, if you pulled your pockets inside out, and then filled them with body fluid, it would be like having a glenofinger. On your groin. On second thought, let’s not pursue that analogy.
The insect’s protuberance releases pheromones, or chemical sexual attractants. And size does matter. The bigger the gland, the more area there is for pheromones to disperse from. Many other lacewings have smelly glands, but they are mostly on their side, or near the anus. Aside from this one group of little lacewings, none have a phallic-shaped gland on the back of their head.
The most solid piece of scientific truth I know of is that we are profoundly ignorant about nature.LEWIS THOMAS
Obviously, I’m focusing on the prurient details of this structure, but it reveals an important point. We discover new things about the world around us every day. Lacewings are common predatory insects, so are of interest because they help farmers and gardeners by eating aphids and other plant nibblers. But knowing about these animals is important not just because there is a dollar sign involved. Studying random little bugs helps us understand how the world works. We discover surprising and unexpected things the closer we look.
“Taxonomy is awesome because we get to discover the true nature of the biology of the earth,” says Winterton. “We can’t manage it unless we know about it. The only way we can know about it is through taxonomy. Essentially, if we don’t go out and discover these plants and animals, then we will never know, potentially, that they had existed.”
If you aren’t discovering something new and unusual in nature everyday, look a little closer. It’s there.
JUST GIVE UP. IT’S IMPOSSIBLE TO BUG-PROOF YOUR HOMEGUEST AUTHOR: GWEN PEARSON.GWEN PEARSONSCIENCE HOW MANY INSECTS do you think are in your home? None? One? A hundred? Some new research suggests you need to step that number up by a factor of 10. Or more. But don’t panic: Insects and their relatives are living peacefully in your home. They aren’t bothering you. Well, except psychologically, now that you know hundreds of them are there.Entomologists have been saying for years it’s not possible to have a completely bug-proof home; now there are numbers to back that up. Scientists carefully collected all the arthropods (insects, spiders, mites, and crustaceans, among others) they found in 50 homes in North Carolina. In every single home they examined, they found extra residents. Of 554 rooms in those homes, all but five (less than 1 percent) had some crunchy squatters. If you think your house is spotless and bug-free, you are wrong. When you move into an empty house, it’s not really empty. You have roommates.Over 400 people volunteered to have entomologists search their homes for bugs after a public call for participation. Because really, how often do you get to have a group of PhDs crawl around your house on their hands and knees for free?
The research group chose a representative selection of homes, big and small, from 7 to almost 100 years old. They limited themselves to visible surfaces under and behind furniture, baseboards, ceilings, and shelves. I asked researcher Matt Bertone what it was like to knock on a someone’s door, introduce yourself, and then spend hours crawling around their floor with a headlamp and tweezers. He said it wasn’t awkward until the end (well, more awkward than what you’d expect if a complete stranger looked under your couch and bed).
Before leaving, the collection team reviewed what they found with the homeowners. It was a bit of a shock for some. “I think they thought we would only find a few things, and we would come back with hundreds of specimens,” said Bertone. His team collected and identified more than 10,000 specimens during the course of the study. On average, more than 93 different species lived in each home. And that is an extremely conservative estimate.
All the houses examined contained flies, beetles, spiders, and ants. Almost all of the houses (98 percent) contained booklice, harmless tiny insects you’ve probably never heard of. Booklice eat mold and mildew, commonly found in starchy paste of books and wallpaper.
Don’t start pricing flamethrowers on Amazon just yet. “It’s very benign,” says Michelle Trautwein, co-author on the study. “We all have these quiet roommates that really don’t have a lot of negative impact on our lives.” Most of the arthropods found were described by the researchers as “air plankton”; they were accidental entrants into the home that got trapped and died there.
For example, the group found gall midges (Cecidomyiidae) in every home, even though their entire life cycle takes place outdoors. There is nothing for them to eat in a human home. Gall flies are also representative of many arthropods found in one other way: They are best seen with a microscope. A big gall fly is about 2 mm long.
“So much of what we find in houses is incredibly tiny, and even if you’re looking for it, you wouldn’t be able to find it,” said Trautwein. Someone who isn’t a specialist might never see them unless they know what to look for. “I’d be crawling around and I’d see fecal specs and I go, ‘Okay, there’s a spider under there,’” says Bertone. “People don’t know what those are. They see those little spots, but they have no idea that it’s spider poop.”
Now that you are suspicious about every speck you might see in your house, here’s what the researchers didn’t find: not a single brown recluse spider or bed bug. They didn’t find very many fleas. Most of the arthropods they found were harmless, minute, accidental visitors lured in from the outdoors to a quiet death from starvation, dehydration, or cobweb spiders.
The number of bugs in our houses makes more sense when you consider that human-built spaces encompass an area as large as some natural biomes globally. But we know far more about the animals outside our houses than in them. “The finding that ‘non-pest’ species made up the majority, … and the sheer number and prevalence of arthropod groups found highlights [our] current lack of knowledge,” says University of Liverpool biologist Crystal Frost.
Many of the insects identified in the study weren’t able to be identified to species—and some of them will probably turn out to be new species. Our homes aren’t the Galapagos Islands, but they are unique environments that organisms may specialize in. We know that some fungi are found only in bathrooms and washing machines, and the same is quite likely of a few insects and spiders from this study. Carpet beetles, clothes moths, and cobweb spiders have limited abilities to disperse on their own, but we move them from place to place with our belongings.