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Since it’s going to be a cold day tomorrow, and since I’m already feeling a little nostalgic for Hawai`i, I dug through my pictures to find these images of moths! I have no idea what kind they are. They could be invasives for all I know. Aren’t they pretty though?

I wish I knew how to identify moths.

I wish I knew how to identify moths.

I could totally see this being a Hyposmocoma, but who knows?

I could totally see this being a Hyposmocoma, but who knows?

 

Hyposmocoma is not the only unusual group of moth caterpillars I failed to observe in Hawai`i. Oh no precious, they are not.

Everyone knows what an inchworm looks like. Inchworms are the caterpillars of a family of moths called, appropriately, geometer moths. They tend to be well-camouflaged, resembling twigs. They eat plants, like most caterpillars, and some are serious agricultural pests.

A handful of Hawaiian species of the genus Eupithecia decided to break with tradition and become carnivores. They take advantage of their camouflage to fool unsuspecting insects into stepping on them. Then they suddenly reach back, grab the interloper with their talon-shaped legs, and eat it.

What’s especially cool is that they are not visual hunters. One species, in fact, hunts in the dark. Instead, they respond to touch: sensitive hairs on their backs tell them when prey is within striking distance. An insect walking on the caterpillar’s head or the front two thirds of its body will be unharmed.

It has been suggested, but not tested, that carnivorous Eupithecia‘s prey capture technique evolved from the “strike response” seen in some herbivorous caterpillars. The behaviour is best studied in the tobacco hornworm (Manduca sexta), the larva of a large sphinx moth. When something brushes against it, it reaches back and sometimes rasps its mouthparts against its skin. This behaviour could serve to startle birds that attempt to eat a hornworm, or to remove parasitoid wasps that would lay their eggs on it (and whose larvae would then eat the caterpillar alive).

By this point you should be dying of curiosity. You want to see these caterpillars in action, don’t you? Well fortunately, the BBC has delivered this nightmarish footage. And io9′s got your animated gif needs covered. Wicked, eh?

I’m going to end this post on a somber note, though. Carnivory by Hawaiian Eupithecia was discovered in the 1970s. The discoverer, Steven Montgomery, described a later foray to the site where he first found a caterpillar chewing on a fly. His report struck a chord with me, calling to mind my own impressions of the Hawaiian rainforest—and this paper is from 1983.

I recently returned to the volcanic cone on the Big Island where I first learned that Hawaii’s caterpillars were insect killers. After 10 years, I was keen to see if the endangered lobelia-like plants still found sanctuary in the steep cinder cone, because a carelessly set fire had destroyed the only other clump of these stately wonders. As I climbed the steep slope, I was stung on the head by a yellowjacket, a recently arrived pest that apparently stole into the Islands with cargo from the mainland. Rounding the top, I searched in vain for the lobelias. With them, half of the native forest plants had disappeared, and signs of rooting by pigs were frequent. Suddenly, a large European boar charged from under the koa tree and fled. I found no caterpillars that day, and heard few native birds. For this place, a conservation opportunity has passed, but on behalf of other Hawaiian forests, it teaches us what is at stake.

These species are not listed as endangered, but their habitat is dwindling; like many endemic Hawaiian species, their days may be numbered.

References
Montgomery, Steven L. (1983). Carnivorous caterpillars: the behavior, biogeography and conservation of Eupithecia (Lepidoptera: Geometridae) in the Hawaiian Islands GeoJournal, 7 (6), 549-556 DOI: 10.1007/BF00218529
van Griethuijsen LI, Banks KM, & Trimmer BA (2013). Spatial accuracy of a rapid defense behavior in caterpillars. Journal of Experimental Biology, 216 (Pt 3), 379-387 PMID: 23325858

On overcast nights in Chicago, the sky is orange with light pollution. A few nights ago, the snow-covered roof of the gym was as orange as the clouds above it, but for the dozens of crows huddled in rows formed by the roof tiles, like sheet music lain on its side at the end of rehearsal.

Let me begin by admitting that when I worked in Hawai`i, I didn’t pay much attention to the tiny moths that I sometimes scared out of the moss. So this is a post about what I missed.

Hawai`i, being remote and geologically active, is famous for its endemic, explosive evolutionary radiations: a single founding population, finding itself far from both its natural food sources and its natural predators, diversifies into a flock of functionally diverse new species in a relatively short time. The honeycreepers, descended from a finchlike bird, are well-known for this; the Hawaiian picture-wing Drosophila flies are another oft-cited example.

There may be more species in the endemic Hawaiian moth genus Hyposmocoma than in the Hawaiian section of Drosophila, and I personally think these moths are way cooler. Consider the many decidedly non-mothlike things these guys do:

  • The caterpillars make cases for themselves out of silk and bits of vegetation, pebbles, and other detritus. Silk-spinning is not unusual for a moth (viz. silkworms), but it’s usually reserved for building a coccoon to protect a pupa. Hyposmocoma caterpillars carry their silk homes on their backs much like a caddisfly larva. This fascinates me because caddisflies are the sister group to butterflies and moths. Is Hyposmocoma case-making an example of reversion to an ancestral state?
  • The cases come in a wide variety of shapes—researchers studying them classify them into such categories as purse-, bugle-, cone-, and burrito-shaped. (Some of them look like oyster shells to me.) You can see some examples of these cases and of the adult moths here. Both moths and cases are quite pretty, but I expect they would be highly cryptic in their natural habitats.
  • Four known species in the genus eat snails; they are the only lepidopterans to do so. I’ll let the researchers who discovered this behaviour describe it:

When [the caterpillars] encounter a resting snail of the native genus Tornatellides, they immediately begin to spin silk webbing attaching the snail shell to the leaf on which it rests, apparently to prevent the snail from sealing itself against the leaf or dropping to the ground once the larva attacks the soft tissue of the living snail. The larva then wedges its case next to or inside the snail shell and stretches much of its body out of its silk case, pursuing the retreating snail to the end of the shell from which there is no escape.

  • Several species have amphibious caterpillars—that is, they can develop successfully either completely submerged in water or on dry land. While many insects, including caddisflies, dragonflies, and stoneflies, have aquatic young that become terrestrial adults, their young are obligately aquatic—they can’t develop out of water. The amphibious Hyposmocoma species are thus unique among insects. This ability has evolved several times independently within the genus. When underwater, the larvae can anchor themselves to the substrate with silk, preventing them from being swept away by strong currents. Scientists suggest that this amphibious lifestyle may be an adaptation to frequent floods in the rainforests in which these species live. Additionally, the limited diversity of insects with aquatic young in Hawai`i compared to such habitats on the mainland may have opened up a niche for these moths to occupy.

So let this be a lesson to me and to all of us who are focused on charismatic macrofauna that we should pay attention to invertebrates once in a while. You never know what they’re up to.

References

 
Rubinoff D, & Haines WP (2005). Web-spinning caterpillar stalks snails. Science (New York, N.Y.), 309 (5734) PMID: 16040699

Rubinoff D, & Schmitz P (2010). Multiple aquatic invasions by an endemic, terrestrial Hawaiian moth radiation. Proceedings of the National Academy of Sciences of the United States of America, 107 (13), 5903-6 PMID: 20308549

Before the snow melted

Friday morning, before the weather warmed up and the rain started, there was fog in the air and a foot of snow on the ground. On the lakefront, you could turn your back on the freeway and see only the ice-covered beach to one side, dark bare branches to the other, and, just barely, the silhouette of a jetty across the frozen bay. The nearer shore, built up with limestone blocks, was encased in eerie bluegrey icicles like a row of ghostly fangs. These dripped onto jagged, jumbled slabs of ice that bordered a dark and uninviting ring of slushy water—inhospitable except for the sewage pipe outlet, where a couple of mallards huddled.

The lake beyond this was a flat expanse of white all the way to the distant point where the ice blurred into the fog. But right in front of me, right in the middle of the little bay, was a black spot on the ice. A falcon—was it a falcon, or a hawk? Does it matter?—was tearing at a carcass, alone on the frozen lake. The gulls flying above seemed to give it a wide berth. A swath of feathers, and maybe blood too, but all colour had drained from this winter landscape, dusted the ice in an arc around the solitary bird; a few of them began to dance away from shore on the wind. The falcon, unruffled, focused on its prey.

A very eldritch holiday

It’s that time of year when nameless horrors prowl the ancient cobblestone streets in the city of my forefathers…I mean, when I re-read some H. P. Lovecraft to escape the saccharine horrors of holiday shopping malls. “The Festival” is one of my favourite Lovecraft stories; it captures the picturesque loneliness of a bleak winter night in a dilapidated town before it plunges into the usual putrescent monstrosities. The opening paragraph is beautiful; the way the story then transitions into your typical Lovecraftian tale seems almost like self-parody:

I was far from home, and the spell of the eastern sea was upon me. In the twilight I heard it pounding on the rocks, and I knew it lay just over the hill where the twisting willows writhed against the clearing sky and the first stars of evening. And because my fathers had called me to the old town beyond, I pushed on through the shallow, new-fallen snow along the road that soared lonely up to where Aldebaran twinkled among the trees; on toward the very ancient town I had never seen but often dreamed of.
It was the Yuletide, that men call Christmas though they know in their hearts it is older than Bethlehem and Babylon, older than Memphis and mankind. It was the Yuletide, and I had come at last to the ancient sea town where my people had dwelt and kept festival in the elder time when festival was forbidden; where also they had commanded their sons to keep festival once every century, that the memory of primal secrets might not be forgotten.

Read the rest, and be glad that whatever holiday family gatherings you’ll enjoy/endure this season won’t be nearly so horrifying. Season’s greetings, earthlings!

At the United Nations two weeks ago, Canada’s Foreign Affairs Minister John Baird spoke out against child marriage. Great. But Canada officially doesn’t fund any international aid agency that provides access to abortion (even by simply providing referals). When asked to clarify about this, International Development Minister Christian Paradis confirmed that this ban extends to agencies helping victims of child marriage and war rape.

In case you are not disgusted by this policy, girls who become pregnant are not actually physically mature (their pelvises and birth canals aren’t physically developed enough for having a baby), resulting in higher mortality and greater risk of other health complications. This is all exacerbated by the socioeconomic conditions in which child marriage tends to be practiced, which tend to limit access to proper health care. And the right of a rape survivor to end a pregnancy seems like a no-brainer. (To say nothing of the right to bodily autonomy. That’s something the Harper Government doesn’t like to be reminded of.)

Below are the texts of three emails I wrote—to Baird, Paradis, and my local MP (who is not a Conservative). Feel free to adapt these letters if you’d like to send one of your own. I’ll be posting any responses I receive in a later post.

Letter 1:

Dear Minister Baird,

You recently spoke to the United Nations about the need for more action on child and forced marriages. Yet last week, International Development Minister Christian Paradis said that Canada will not fund projects that give such child brides, or survivors of rape in war zones, access to abortions.

I understand that this policy is consistent with the government’s decision not to fund abortion services under its global maternal health plan. However, the need for an exception to this policy in cases of child marriage and war rape is obvious and pressing. According to Human Rights Watch, girls under the age of 20, and especially those under the age of 15, who become pregnant are more likely to die of complications from pregnancy and face other serious health consequences, largely due to their physical immaturity. Further, the right of women who become pregnant as a result of rape to terminate their pregnancy should be beyond question.

While I applaud your efforts to curb the practice of child marriage worldwide and to promote maternal health, survivors of sexual violence need protection as well, and sometimes abortion is a necessary part of that process. I urge you to reconsider this policy and stop leaving rape survivors behind.

Sincerely,

[helikonios]

Letter 2:

Dear Minister Paradis,

You recently said that Canada’s government will not fund international aid projects that allow access to abortions for child brides and survivors of war rape.

I understand that this policy is consistent with the government’s decision not to fund abortion services under its global maternal health plan. However, the need for an exception to this policy in case of child marriage and war rape is obvious and pressing. According to Human Rights Watch, girls under the age of 20, and especially those under the age of 15, who become pregnant are more likely to die of complications from pregnancy and face other serious health consequences, largely due to their physical immaturity. Further, the right of women who become pregnant as a result of rape to terminate their pregnancy should be beyond question.

Abortion is sometimes a necessary part of health care for women and girls in these horrifying situations. It is hypocritical of the government to speak against sexual violence and child marriage yet deny survivors the care they need. I urge you to reconsider this policy and stop leaving rape survivors behind.

Sincerely,

[helikonios]

Letter 3:

Dear [MP],

Last week, shortly after Foreign Affairs Minister John Baird spoke at the United Nations denouncing sexual violence and child marriage, International Development Minister Christian Paradis confirmed that Canada would not fund any aid agency that provided these survivors of rape with access to abortions.

This policy prevents girls from accessing necessary health care. Girls who become pregnant are still not physically mature, and face higher mortality and other health consequences as a result. Furthermore, the right of rape survivors to be able to choose to end a pregnancy should go without saying.

As a resident of [riding], I urge you, when Parliament resumes, to work towards changing this policy. Preventing violence against women worldwide should be a bipartisan goal, and treating survivors of such violence is just as important.

Sincerely,

[helikonios]

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