The Smithsonian has a cool blog post about using satellite images to track insect damage to trees over time. Increasing temperatures (especially increasing winter temperatures) and drought conditions have led to outbreaks of bark beetles like the mountain pine beetle throughout the western U.S., causing widespread damage to millions of acres of forest. As large swaths of trees are killed by the beetles, they become a fire hazard. Scientists are using the satellite images to track patterns of insect outbreaks and correlate them with weather patterns.
Robots that can detect and track odors such as gas leaks or environmental spills could become increasingly useful in the future, and insects are a useful model for such robots. Scientists from the University of Tokyo have built a small moth-driven robot to study how moths detect pheromones (chemical signals). By understanding the neurological and behavioral processes by which a moth detects and tracks down an odor, their goal is to eventually build a robot “brain” that can track odors as well as the moth. They have recently published their findings in the Journal Bioinspiration and Biomimetics.
The FDA has recently approved a new flu vaccine called Flublok. This vaccine is unique because it is grown inside insect cells from the fall armyworm moth rather than in chicken eggs. This vaccine can be produced more quickly than traditional vaccines. It can be used by people who are allergic to eggs and doesn’t include thimerosal, which contains mercury.
Exploiting insect guts for use in the biofuel sector
Scientists have been looking for enzymes to effectively break down lignin in biofuel facilities in the guts of insects. It turns out the microbes in the guts of grasshoppers may be potential candidates for future use in this manner.
In a post about singing insects, I talked about how people in China keep crickets and katydids as pets. USA today published an article recently about people in the US keeping insects as pets. Ill admit that I did have hissing cockroaches for a time when I was in high school. But I am glad to see that others in this country do this as well!
CSI insects: Museums highlight using insects to fight crime
Forensic entomology is a branch of science that uses insects to indicate things about crimessuch as how long a body has been dead, or if a corpse may have been moved. A few museums have exhibits about this branch of scienceI wish I were in the area of one, Id definitely check it out.
This will be a regular feature on the blog that summarizes recent scientific papers discussing the role of insects in human society. Since Chelse and I are ecologists, the papers we review will primarily examine insect effects on people from a biological perspective, but we would love to hear about relevant papers from other disciplines. Our first entry deals with a recent review of the ways that insects have been used in warfare throughout history.
Jeffrey Lockwood, a biologist and philosopher in the Department of Philosophy at the University of Wyoming has published a review of the many ways that insects have been used in warfare and as instruments of torture throughout history. The material covered in the review paper is expanded upon in his book Six-Legged Soliders: Using Insects as Weapons of War. I have not read the book, but I am planning to read it now. The paper was really interesting, if at times quite disturbing.
Lockwood gives a chronological overview of the ways that insects were used in warfare from prehistoric to modern times. The Mayans, ancient Greeks, and Middle Eastern cultures would fling hives at enemies. The Mayans would even make pottery hives for bees to colonize. The hives would then be plugged with grass and flung at enemies as “bee grenades”. Over time, use of insects in warfare has become more technical, with the use of insects in biological warfare.
Use of insects in warfare seems to fall into three categories. (1) The use of stinging and biting insects to repel attackers. This usually involved releasing insects into tunnels or flinging hives or clay pots filled with bees at enemies. In Great Britain, for example, many castles had recesses in the walls to hold bee hives, which were dropped onto attackers. (2) The passive use of insects, especially disease vectors. This mainly involved forcing enemies into areas with insects that transmit diseases. For example, during the U.S. Civil War, Confederate General Johnson managed to trap Union troops along the Chickahominy River outside of Richmond Virginia, an area known for malaria. Within a few months, more than half of the union forces were too sick to fight or hospitalized. (3) Development of insects for biological warfare. This involves more technical advancement than simply hurling hives at enemies. During World War II, governments began seriously funding research into the use of insects for biological warfare. This included using insects to transmit human diseases to opposing troops and the use of insects to compromise enemy food supplies. Insects could be used to compromise food supplies by developing insects as crop pests and by using insects to transmit livestock diseases. Use of insects in biological warfare has continued to modern times.
This paper was an interesting read. I had no idea that insects had been used so extensively in warfare throughout history, but it makes sense. Lockwood concludes with a warning that modern bioterrorists can cause outbreaks with the use of insect disease vectors or do significant damage to food supplies by reintroducing eradicated insect pests. Insects have been used in warfare throughout history and this will likely continue.
Weekly, well be posting news stories about how insects affect people. Here are a couple of stories from the last few days.
Many people have been suggesting now that one way to make our food source more sustainable is for people to eat insects. Theyre cheap and a good source of protein. Its not uncommon in other countries, but most people I know are still freaked out about in the US. Theres even a TED talk about it. And a very well-done blog devoted to it. And even Dr. Oz recommends it! (So it MUST be good, right?) This movement has been growing some momentum, and its even considered in to eat insects right now, according to The List of whats supposed to be in/out this year. Although lots of different companies market things like insects in candy as novelty items, this week, there was a news story about a company using cricket-enriched flour in their energy bars. The crickets are milled, so youre not going to bite into a crunchy leg. The company hopes this is a way to ease Americans into eating insects. I, personally, really like this idea. So, maybe a meal of mealworms isnt that far away for you!
Waxing and endangered crabs? (Not the delicious kind.)
A bloomberg news report (and subsequently, many other news outlets) suggest that waxing will cause crabs to be endangered. (Not the kind you had for dinner last night.the itchy, pubic lice variety.) Make sense, right? No hair, no place for these itchy insects to live. But making an appointment at your local waxer is not likely to completely eradicate this species. A well-reasoned (and hilarious) response from @bug_girl shows there really no data to support this. The paper thats often cited in these news stories shows a decline in pubic lice from a certain area in England, yes. But they dont show data on waxing rates. From anywhere. They tell anecdotal stories about it. Bug Girl dug into the topic a little more, and shows that baldness is the least used pubic hairstyle, even for college-age women, who are more likely to groom in this manner. And if theres hair around, there is the potential for crabs! So, in short, waxing may get rid our your crabs (ewwyou have crabs?), but the species isnt likely to be wiped off the planet anytime soon. BUTwhat if it was? Slate News reported a satirical piece on if this happened, and it involves Sex in the City, dinosaurs, crabs and asteroids.
Corpse eating flies help reveal hidden species
Insects are often used as bio-indicator speciesan organism that is used to signal something about the environment. For instance, the composition of insects in a stream can indicate pollution levels in a stream because only a few insects can live in a very polluted stream. Last year, scientists reported that they are able to detect rare animals living in the forest of Vietnam by sequencing DNA found in blood from leech guts. It is hard to study rare species simply because theyre hard to find, and mammals, like other animals, often try to avoid detection by potential predators by making them selves hard to see in the thick forest. This week, scientists published data showing that they are also able to use DNA sequences from gut contents of insects, flies that feed on corpses of animals, to detect rare mammals in the rain forests of Côte dIvoire. Sampling carrion-eating insects may prove a valuable tool in the future for studying endangered species, and ultimately, understanding how best to conserve these species. Yay, flies!
You’ve undoubtedly heard many insects making sounds, and maybe you find certain noises of theirs annoying, such as flies and bees buzzing. There are some true musicians in the insect world: namely, orthopterans (grasshoppers, katydids, and crickets) and cicadas. There are countless scientific studies on insect songs, ranging from descriptive studies that detail the particular song of a species, to how temperature affects insect songs. If you’re interested, there is a blog dedicated solely to the music of nature, which discusses insect songs much more in-depth than I will here.
I started thinking more about the songs of these insects when I started working at my current field site at the University of Houstons Coastal Center, a remnant of rare tallgrass coastal prairie along the Gulf Coast of Texas. You can hear different orthopterans (grasshoppers, katydids, and crickets) calling at different times of the day. The softer thrills of southeastern crickets while it’s dark, and loud calls of katydids during the heat of the day, which to me often sound like those sprinklers with rotating heads.
Not knowing too much about these different insect calls, I started looking for a good resource on the subject and stumbled across this wonderful book by Lang Elliott and Wil Hershberger. It describes 72 species of orthopterans and cicadas that produce songs in east/central North America. The best part, for an insect geek like me, is the CD it contains that provides sound clips of many of these insects singing, and if you’re particularly interested, you can learn to identify many species of these singing insects by learning their calls.
Most of these songs are produced to find a mate, and it’s more often the males calling to attract females than visa versa. Sometimes calls let another male, potentially rivaling for females know not to get too close, that this area is claimed. A few band-winged grasshopper species (characterized most simply by bright, colorful wings) produce a clicking sound both in an attempt to scare off a potential predator, and, again, to attract mates.
So, are people affected by these insect musicians? My guess would be if you asked this question to the average urban or suburban American, they would say no. In these settings, we hear fewer insects simply because there isn’t much habitat for them in cities, and even where there is grass, it’s often a lawn that is mowed or treated with pesticides. If they happen to be observant and live in the areas of certain annual cicadas whose calls are harbingers of summer, they may say yes. Maybe folks in rural areas would be inclined to admit a nostalgia for or distinct feeling of summer upon hearing insect songs, as this is when many of these singing insects are active.
David Attenborough talks about what is considered one of the most spectacular gatherings of insect musicians globally, the songs of 17-year cicadas in the midwestern US in the BBCs Life in the Undergrowth (which, as a side note, is a must watch series for anyone that appreciates insects).
The first time I experienced this phenomenon was as a child in 1987, growing up in Northern Kentucky. Once they emerged, cicadas appeared to be dripping off plants. You could not walk down the sidewalk without stepping on one. My mom and I made cobblers from blackberries we’d picked. My aunt bit into something crunchy, and sure enough, a cicada had snuck into the cobbler. Either way, the major thing I remember was people complaining about them. In places with many old trees where the ground has not recently been tilled, the screeching can, as Attenborough says, be deafening. This large emergence of cicadas has other important effects on ecosystems, including effects nutrient cycles (Yang 2004), and providing huge pulses of food for predators, which often causes a boom in predator populations, such as red-winged blackbirds that also have distinctive calls (Strehl and White 1986). Although not everyone appreciates this phenomenal spectacle, it is certainly a wonder of nature.
Apparently, in certain areas of Asia, however, singing insects are revered. In Japan, people sell insects as a profession (and are called mushiya; there is a book chapter about this here). People keep them in their houses in the winter time so they can hear their songs year-round, and plan vacations to places where certain insects are known to call. Calling insects are also important to people in China: there has even been recent press about this (although, the title is misleading the insects are not singing for their food). One man, who apparently carries around a singing orthopteran in his pocket is quoted as saying, During the winter it is dry and cold and you cannot hear any birdsong. The sound of bush crickets makes me happier. That would make me happy in the cold, gray winter, too!
But now there is evidence that singing insects are affected by our noise as well. A forthcoming study in Functional Ecology has gotten a lot of public press recently (Lampe et al 2012) provides evidence that male grasshoppers near German roadsides alter their songs to be better heard by potential female mates. This is the first evidence that insect musicians must now compensate for human noise. I wonder what other insects may be changing their songs because were a noisy species?
Human feelings about these singers may range from annoyance to appreciation to reverence. I’d like to do more research but haven’t seen any studies that attempt to quantify how humans feel about the sounds of different insects. Although Japanese and Chinese cultures are certainly influenced by insect songs, their economies must be affected in some small way, I haven’t yet found any studies that quantify this.
I, for one, have gained a fondness for insects songs, and a desire to be able to identify insects by their songs since my time working in prairies. Do you notice these singing insects? Do they affect your life in any appreciable way?
We often get asked, why? Why study insects? Even other scientists who agree that insects are interesting don’t necessarily think that insects may have important effects in ecosystems compared to bigger animals. Angela and I were at a grassland meeting together, and, over lunch, a well-respected professor laughed at us when we were discussing a future experiment looking at how important grasshoppers were to grasslands at our field site. You’re talking about a bug on a leaf!, he crooned, while laughing hysterically.
So why? Other than the fact that we personally love insects, insects have very important roles in ecosystems, and believe it or not, to human society and well-being. Science has shown this. We got a paper that will soon be published reviewing this subject (well post about it soon!). E. O. Wilson, a famous ecologist, and insect lover wrote an article entitled The little things that run the world where he claimed that humans would not survive more than a few months if all insects were removed from the Earth overnight. Luckily, we’ll never know if this is true. But, we know that they’re extremely important to humans in many ways.
We’ll use this blog to highlight the ways that insects affect us humans (both positively and negatively!). Selfishly, this is also a place for us to keep these examples documented for our teaching and research purposes. We hope that you get something out of this. Feel free to contact us to share your experiences (or examples we might not be aware of) regarding how insects affect you!