It’s been the kind of week where stress levels have been on the rise and I’ve asked myself more than once why I’m killing myself over a million and one things instead of drinking beer and relaxing on a patio somewhere.
Finding the energy and drive to keep pushing forward, writing and making progress even when faced with what seem to be insurmountable obstacles is tough, but it helps to stop, take a breath, and look up from the dark pit of deadlines from time to time and just ogle over a fly or two to remind myself why I love what I do.
In case you find yourself in a similar position going into the weekend, here are a couple of shiny flies which I hope will cheer up your day like they did mine.
While some common names are great descriptors of a moth’s biology, some can be rather deceiving. Take the Banded Tussock moth for example, which although banded, isn’t a true tussock moth! While the “true” tussock moths are in the subfamily Lymantriinae, this moth is actually a tiger moth in the Arctiinae. The larvae of this moth have large tufts of hairs that are reminiscent of those found on “true” tussock moth caterpillars, which is where the common name comes from. These tufted larvae can be found feeding on a wide diversity of deciduous trees.
Tiger moths are known for their ability to hear incoming sonar pings of bat predators, and some have even evolved sonic countermeasures. The Banded Tussock moth was one of the first moths shown to protect themselves from bats by emitting high-frequency sounds (Dunning & Roeder, 1965). Remembering back to my undergraduate Physiology classes, I recall there being 2 ways in which these sonic displays could deter bats: 1) as a warning that the moth was distasteful and the bat should move on to something more tasty (the acoustic equivalent to the bright colours found on many other tiger moths and insects), and 2) some moths emitted a frequency so close to the bat’s sonar that they could disrupt the bat’s orientation and become hidden in a curtain of sonic feedback. Which method this species enlists I’m not sure, but I find it amazing that some moths have adopted such extreme defenses.
Of course, being loud isn’t going to save you from all potential threats, like the tachinid parasitoid Blondelia hyphantriae.
———————- Dunning, D.C. & Roeder, K.D. (1965). Moth Sounds and the Insect-Catching Behavior of Bats, Science, 147 (3654) 174. DOI: 10.1126/science.147.3654.173
Tussock Moth (?) – Bella Vista Cloud Forest Reserve, Ecuador
Another day in the jungle, another moth I can’t identify. I’m less confident that this is a true tussock moth (Erebidae, Lymantriinae), but it does have the posture and the somewhat fluffy legs. No matter what it is, it was a jewel to find while in the cloud forests of Ecuador.
As a bonus, I even managed to snag a little nematoceran fly in the photo!
I may be nearly useless with moth identification, but this is one I know by heart. Of course, this isn’t really brag worthy since there aren’t many moths with an iridescent blue thorax and yellow head, but I’m working on baby steps here.
Just because I can identify it doesn’t mean I can place it in the correct family however! When I was an undergrad (back in the day when I had to walk 10 miles uphill both ways, etc) I was taught the tiger moths were a family unto themselves. Since then however, they’ve been sunk into the family Erebidae, causing me much confusion.
The Virginia Ctenucha feeds on a variety of grasses and sedges as a caterpillar, and adults are active from late spring to mid summer.
What feeds on Virginia Ctenucha though? Compsilura concinnata, a tachinid fly that was introduced to North America to combat Gypsy moth (Lymantria dispar) in the late 19th and early 20th century. As is wont to happen with poorly understood ecology and introductions, Compsilura concinnata turned out to be a broad generalist, and is right at home within a wide diversity of caterpillar hosts. There’s concern that this “new” parasitoid is a contributing factor to declining saturniid moth populations in eastern North America, but the fly appears to be under heavy pressure from a hyper-parasitoid species of trigonalid wasp, which appears to be keeping fly populations low enough to prevent eradication of native moths.
——— Kellogg, S.K., Fink, L.S. & Brower, L.P. (2003). Parasitism of Native Luna Moths, (L.) (Lepidoptera: Saturniidae) by the Introduced (Meigen) (Diptera: Tachinidae) in Central Virginia, and Their Hyperparasitism by Trigonalid Wasps (Hymenoptera: Trigonalidae), Environmental Entomology, 32 (5) 1027. DOI: 10.1603/0046-225X-32.5.1019
Exciting news since the last Weekly Flypaper: Piotr Naskrecki, orthopteroid taxonomist, photographer, and author (Relics and The Smaller Majority) has started a new blog — The Smaller Majority. So far Piotr has been killing this whole blogging business, with fascinating posts on tropical entomology and macrophotography tips. I’m pretty sure I bookmarked every post he made for future reference, but here are a few of my favourites:
Apparently I missed the memo about Photo Bombing blogs, as Matt Bergeron, Dave Stone and Alex Wild all showed off gorgeous photos of bombyliid bee flies.
Emerald Ash Borer (Agrilus planipennis) has continued it’s inevitable march across eastern North America, this week being detected in Connecticut for the first time. What’s important about this is that Cerceris fumipennis, a solitary wasp which specializes on buprestid jewel beetles, was the first to detect it’s presence in the state. This is the sort of Bio-surveillance that Phil Careless and the rest of Team Cerceris had hoped for, and now hopefully more government agencies will invest in expanding this simple monitoring tool.
I’ve seen a bunch of people start blogs only to watch them peter out after a few weeks/months. As a blogger who has a relatively small (yet loyal) readership, I can sympathize with this post on Why Blogs Fail.
Carl Zimmer was a plenary speaker at the annual meeting of the Society for the Presevation of Natural History Collections a few weeks ago, and they just posted his talk on YouTube. It’s long (more than an hour), but it’s an interesting talk and well delivered.
While I was perusing Twitter this afternoon, Dr. Matthew Francis, a physicist/science writer who I follow, randomly started spurting out astronomical terms for fun1. One of those terms was Musca, which obviously got my attention in a hurry, and I asked what was so astronomical about a common genus of flies (you can read the full conversation at the bottom of this post)2.
Turns out Musca happens to be a constellation of stars observable in the Southern Hemisphere! It was “described” in 1597 or 1598 by Petrus Plancius, a dutch astronomer who clearly has an excellent imagination. Although it was originally called Apis (the Bee), it was changed to Musca (the Fly) in 1752 to avoid confusion with the nearby constellation Apus (literally “no feet”, in honour of birds-of-paradise, which at the time were believed to footless). But why name a constellation after an insect? Plancius named a neighbouring constellation Chamaeleon and decided it would need a source of food!
Seeing as I’m kind of a fan of flies3, I checked to see where the constellation was located so I could look for it the next time I’m on the southern half of the planet. Much to my delight, Musca is found immediately “below” the Southern Cross, the only constellation I knew about in the Southern Hemisphere, and something which I had not only seen before, but had photographed!
I quickly opened Lightroom to check my photos of the Southern Cross and see if I could make out Musca, and wouldn’t you know it, I found it! Not only that, I got good photos of it, and not just from one location, but from 2 totally different countries on 2 totally different trips! SWEET!
The Southern Cross, Musca and Chamaeleon over the Heath River
This photo was taken at the Heath River Wildlife Center on the border of Peru & Bolivia in 2007. In case you can’t see a cross, a fly or a chameleon, here they are with appropriate lines:
The Southern Cross, Musca & Chamaeleon over Peru & Bolivia
Not only did I manage to capture this celestial fly in Peru, but I also got photos of it in Ecuador while looking for real flies in 2009.
The Southern Cross & Musca over Yasuni Research Station, Ecuador
Here’s a massive crop showing the Southern Cross and Musca more closely:
The Southern Cross (top) with Musca (bottom half and faint) over Yasuni Research Station, Ecuador
When out in remote dark-sky locations deep within the Amazonian jungle, both constellations are visible to the naked eye, but picking them out from several thousand other stars and the Milky Way is a bit more of a challenge.
Musca within the Milky Way – Yasuni Research Station, Ecuador
I can’t wait to get back to South America to collect & photograph more flies, both the corporeal ones within the jungles of Earth and the shiny one above it!
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1- I don’t know either, it must be a physicist thing. They’re all about the entropy I hear…
Evolutionary biologists from around the world have converged on Ottawa this weekend to partake in the First Joint Congress on Evolutionary Biology. Luckily for those of us who couldn’t make it, there are a ton of people tweeting about talks, the conference and evolution in general. I’ve been watching the #evol2012 hashtag all morning while writing this, and although I’m even more jealous of those that are attending the conference in person, I’m glad I can enjoy a slice of the conference through the tweets of others!
1- Not sure whether I’ve explicitly mentioned this here on the blog, but I’m starting my PhD at the University of Guelph in September! Lots of work to finish up before then, but I’m really excited to become a student again.
You may have noticed the Weekly Flypaper has been missing the past two weekends. I have a good reason for missing one, and a not so good reason for missing the other…
First, the good reason. I took part in the Rouge Park BioBlitz in Toronto, and along with 230+ other naturalists, taxonomists and volunteers, we scoured Rouge Park (soon to be Canada’s first urban National Park) for all signs of life, trying to identify as much as possible in 24 hours. Although the numbers are still coming in, the official species count is already nearing 1,300 species, all sighted or caught in 24 hours (and more than 800 of those were identified within the first 24 hours too)! That is an absolutely amazing number, and sets the bar very high for future BioBlitzes! The Guelph crew had a great time, and I think we contributed almost 100 insect species identifications, including 60+ flies. Lots more came home with us, and we’ll be getting names on them in the near future to be added to the list. The arthropod coordinator, Antonia Guidotti of the Royal Ontario Museum has posted an awesome synopsis of the BioBlitz over at the ROM Blog.
The other reason? I was lazy last weekend and didn’t get around to doing it. Oops.
So with 3 weeks worth of links, and major holidays upcoming in Canada & the USA, I suggest you grab a cold drink, find a comfy spot, and clear your schedule, because the Bugosphere has been busy! Continue reading »
After some not-so-gentle encouragement (ahem, Geek), I finally updated my blog list with all of the new and different blogs to which I subscribe. I can’t link to all of the great content that’s produced by the online entomological community, but I highly recommend giving each of those blogs a look to see what they’re up to!
General Entomology
If you’ve ever wished you could have seen a dragonfly with a 6′ wingspan, Ed Yong explains why birds are partly to blame. Jerky birds ruin everything.
The role of science communication in academia has been gathering quite a lot of attention lately, even garnering a discussion in Nature (well, their blog, not the journal itself. Yet):
Finally, I leave you with two videos this week. One with hypnotizing footage of a dragonfly in flight, and the other a viral song that’s been on loop on my computer all week.
UPDATE: It turns out my first theory involving oestrid bot flies was full of holes. I’ll leave it up because the biology of the individual parasites is accurate and interesting, but see the bottom of the post for an accurate description of what happened in the photo. I apologize for the misinformation.
Recently, I was catching up on Twitter late at night when @PsiWaveFunction shared a link to a photo on Reddit that stopped me cold in my tracks and that has kept me morbidly fascinated since. I’ve spent the better part of a day thinking about the photo, and I think I’ve pieced together the series of events and organisms that lead to the case of the mystery myiasis. If my theory is correct, this might be one of the coolest cases of parasitism I’ve ever encountered, and features a fly who’s life history beautifully illustrates the intricacies of evolution, another fly that’s threatening the birds which helped Darwin develop his theory of evolution through natural selection, and a bird who is being selected against by the worst possible luck.
Normally I’d include the photo in question right about here, but out of respect for those victims readers who are a tad squeamish at the sight of parasites (or birds), I’ll simply link to it and allow your curiosity to battle your better judgement1. I’ll give you a moment to decide and, should you accept the challenge, digest what you’ve just seen.
So, were you amazed? Disgusted? Wondering what the hell you were looking at? If you’re like me, you probably felt a little bit of all three, and then immediately went back to take a closer look.
Welcome to the wonderful world of warble flies (family Oestridae)! Each of those oddly formed lumps is actually a bot fly maggot which has burrowed beneath the skin of the chick to feed and develop. You’ll notice two dark marks on the exposed end of each maggot; these are the spiracles through which the maggot breathes. After a few weeks, each of the maggots will wriggle free from the bird, drop to the ground and pupate, eventually emerging as an adult ready to breed. Normally the host is left mostly unharmed after providing safe harbour for a bot fly, but in this case I suspect the bird might have problems due to the shear number of maggots present (at least 15 that I could make out).
Dermatobia hominis -- Photo by J. Eibl, Systematic Entomology Laboratory, USDA.
What’s odd about this situation2 is that these bot flies have parasitized a bird. You see, almost all bot flies are mammal parasites, infesting anything from rodents to elephants, and are usually very specific about their host species. One bot fly however, Dermatobia hominis, is a generalist, and has been recorded infesting a number of different animals, from humans and monkeys to dogs and cats, and of relevance to this story, birds on occasion. In a family of narrow specialists, it’s a wonder that D. hominis is such a broad generalist; until you learn how D. hominis distributes its offspring — by hijacking other flies to serve as expedited egg couriers.
Psorophora sp. (Culicidae) with D. hominis eggs attached. Illustration by A. Cushman, Systematic Entomology Laboratory, USDA.
After mating, female D. hominis will snatch up other parasitic flies, like mosquitoes, flesh flies and muscid flies3, and lay a clutch of eggs on the enlisted fly. When the carrier fly locates and lands on a host to feed4, the body heat of the victim signals the bot fly egg to hatch and fall from the carrier onto its new home, where it quickly burrows in to begin feeding. This amazing life cycle means that the female bot fly has little control over where, and on what species, its offspring ultimately end up infesting, resulting in a nearly random generalist parasite that must be able to survive on whatever host it finds itself on, including our small bird.
Obviously the natural world is a complex system, and unfortunately for our bird, it’s full of a diverse array of parasites, all looking for a free meal. Let me introduce you to another player in this saga, Philornis downsi (Muscidae), a fly native to continental South America and Trinidad & Tobago, where our unfortunate bird lives.
Philornis in nasal cavity of deceased bird. Image from O'Connor et al. 2010
While adults are unassuming, feeding on pollen and nectar, Philornis downsi larvae are brood parasites of nesting birds. Hiding out of sight during the day in the bottom of the nest, maggots emerge after dark to crawl within the nasal passages of developing chicks, feeding on their blood and tissue, sapping their energy. As the maggots continue to grow, they begin feeding elsewhere on the nestlings, causing severe damage and ultimately death. Throughout the Galapagos, where the fly was introduced sometime prior to 1964, Philornis downsi has been causing nestling mortality rates as high as 95% in Darwin’s finches, the unique birds who’s diverse beak shapes inspired Charles Darwin’s theory of evolution by natural selection. While there has been a great deal of work done on P. downsi in the Galapagos in an effort to save these ecologically important birds5, I assume it is also receiving research attention in its native range, which is where we return to Reddit, our original photo and what I think happened.
Of all the parasites, in all the nest boxes, in all the world, she flies into mine.
My theory was wrong. See below for information about the actual parasite.
A recently mated female Dermatobia bot fly was looking for a carrier fly
A female Philornis downsi happened to fly by, was quickly snatched by the bot fly and entrusted with a load of bot fly eggs
The female Philornis was released, and continued her search for a bird’s nest to deposit her eggs in
Finding a nest, the Philornis female walked around, laying eggs among the nesting material, and happened to tread across the young bird in the nest
The bot eggs, sensing the proximity of a warm-bodied host, hatched and quickly found their way to the unlucky bird’s face
The Philornis female finished laying her eggs and took off from the nest, leaving chaos brewing in her wake
Later, a social media-conscious research assistant comes along, finds the disfigured nestling, and does the only logical thing; takes a picture and posts it to the internet for all to enjoy!
Of course, this is only a theory based on a single photo and a very small fraction of information about the team’s research, but given the evidence and biology of the species potentially involved, I think it’s certainly a plausible hypothesis. There are a lot of potential fallacies in my theory, like whether the bot fly larvae are actually Dermatobia, or whether Dermatobia even uses Philornis as a vector (although it’s known to use 11 species of Muscidae), but these are the sort of questions that can be observed and tested eventually. Hopefully the researchers behind the photo will rear the maggots from the bird’s face, identify the parasites involved, and then publish their work so I can find out whether any of these ideas turned out to be accurate6.
Whether my theories were correct or not, the fact that they’re even plausible keeps me interested and excited about entomology and the intricate roles parasites play in our daily lives!
References:
Eibel, J.M., Woodley, N.E. 2004. Dermatobia hominis (Linnaeus Jr., 1781) (Diptera: Oestridae). The Diptera Site. Accessed June 6, 2012. http://1.usa.gov/MbTexi
Fessl B, Sinclair BJ, & Kleindorfer S (2006). The life-cycle of Philornis downsi (Diptera: Muscidae) parasitizing Darwin’s finches and its impacts on nestling survival. Parasitology, 133 (Pt 6), 739-47 PMID: 16899139
O’Connor, J.A., Robertson, J. & Kleindorfer, S. (2010). Video analysis of host–parasite interactions in nests of Darwin’s finches, Oryx, 44 (04) 594. DOI: 10.1017/S0030605310000086
UPDATE June 7, 2012 @ 3:30PM EST: It turns out that the maggots in the bird’s face aren’t Dermatobia hominis, or even bot flies of the family Oestridae at all! After doing some further research, I’ve learned that they are more likely to be another species of Philornis fly. I was totally unaware that there were flies outside of the oestrid bot flies which burrow into the skin of hosts and form warbles like these, but it turns out there are.
While Philornis downsi are ectoparasites that feed on nestling birds as I described, it seems that there are several species in the same genus which burrow within the skin and form welts similar to oestrid bot flies. Here’s an example of Philornis vulgaris infesting a Tropical Mockingbird nestling from Colombia:
Philornis vulgaris infestation from Amat et al. 2007
Looks vaguely familiar no? I think it’s safe to say now that this is what happened in the original photo and not the complex tale of 2 parasites like I described above.
I’m incredibly embarrassed by my Taxonomy Fail here (which holds a TFI of 11.3). Although the biology of the two parasitic species I originally discussed are accurate, the chances of them having anything to do with one another appear to be unlikely. I sincerely apologize for publishing a story that spread such inaccurate information, and I’ll do my best to not let it happen again.
Note to self: don’t assume you know anything, especially when it involves parasites.
On the bright side, I learned something new about Diptera (and humility) today, and we can all rest comfortably knowing that there are multiple, unrelated groups of flies that get under the skin of their hosts. Because I’m sure that makes everyone feel better.
More information about subcutaneous Philornis:
Amat, E., J. Olano, F. Forero & C. Botero 2007. Notas sobre Philornis vulgaris (Couri, 1984) (Diptera: Muscidae) en nidos del sinsonte tropical Mimus gilvus (Viellot, 1808) en los Andes de Co- lombia. Acta Zoológica Mexicana, 23(2): 205-207. http://bit.ly/LwsHh1
Uhazy, L.S., Arendt, W.J. 1987. Pathogenesis associated with philornid myiasis (Diptera: Muscidae) on nestling pearly-eyed thrashers (Aves: Mimidae) in the Luquillo Rain Forest, Puerto Rico. Journal of Wildlife Diseases 22 (2): 224-237. http://bit.ly/KlXBGR
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1- If you can’t decide, I vote you click and look. You can thank me later.
2- Beyond the whole face-of-a-million-maggots of course.
4- Something these blood-sucking flies have evolved to do quite well obviously. The fact that bot flies “cheat the system” in this regard, getting their eggs to their host without needing to invest energy in complex host-finding senses, just goes to show that nothing is more awesome than evolution in action.
