#7 :: Insect Collections
Intro music: "InsectaLoop" by Jake McCarthy.
JAKE Hello. You're listening to InsectaPod Cast Episode 7, Insect collections. InsectaPod Cast is a product of the Michigan state University Department of Entomology and its home on the web is www.insectapodcast.com. I'm Jake McCarthy, the voice you'll hear is Anna Fiedler's, and this is InsectaPod Cast.
ANNA My 11-year old neighbor Madison found out that I shared her interest in insects, and, in fact study them. One day she confessed to me “I imagine you up in your attic, with lots and lots of bugs”. She envisioned boxes upon boxes of pinned insects up there, and me sitting at a microscope looking at them, in a space with 2 tiny windows at either end. This is one of the quintessential images of The Entomologist; people often picture us either swinging a butterfly net in a field somewhere looking for insects to pin or hunched over a microscope looking at those pinned insects. In this episode, we look at what prompts three different entomologists to create insect collections, how they feel about the insects in them, and how some collections are anything but a box full of pinned insects.
Julianna Tuell is a Postdoctoral researcher in the Small Fruit Entomology lab at Michigan State University, where they study pollination of blueberries, strawberries, and raspberries. She has a tremendous collection of insects – 25 glass-topped drawers full, each with hundreds of specimens in it; because her focus is on pollination, almost all of the insects in Julianna’s collection are bees. Like many people, her collection started as a class assignment and that means she didn’t start collecting until she was into her twenties. However, she always had an interest in bees and that interest has grown as she works with them.
JULIANNA I think actually, they’re cute. I mean, they’re fuzzy, and they’re collecting pollen. They’re not, if you, they’re one of the only insects that actually collects pollen as a food source, as opposed to killing another insect, or using some other food source. They use pollen, and so they have this close relationship with flowers that I also love, and I think it’s just a great- it’s just a wonderful mutualism to study.
ANNA It turned out that the class she made the collection for became her favorite class, and turned Julianna on to studying insects, first, as a Masters student looking at the interaction between an insect and a root fungus that attacks asparagus. She then got a PhD looking at pollination of blueberry, in the lab where she currently works. Julianna, like many entomologists, collects insects with a purpose in mind, a question she wants to answer. In her case, she was looking at the bees that pollinate blueberry crops in Michigan.
Julianna has discovered through her work that there is a tremendous diversity of bees in Michigan blueberry crops. Of note here is the fact that the honeybee is not native to the United States, but there are a host of other bees that are native and Julianna’s study, as well as her insect collection, are focused on these native species. Although honeybees are abundant pollinators, native bees may do a better job of pollinating some crops, leading to higher production.
Why do we care so much about the native pollinators that are in blueberry?
JULIANNA Well, because blueberry is a native plant and bees, honeybees, are not the most efficient pollinator. You can inundate a field with honeybees and they’ll do the job, but with honeybee collapse disorder there’s some concern that it’s going to be more and more expensive to get honeybees and if you need so many of them for this crop, then you should look at other pollinators that are actually much more efficient. Bumblebees are really good, and there are a bunch of solitary species that are good pollinators of – better pollinators – than honeybees. So if we can boost their numbers, then it’ll be a benefit to that crop.
ANNA Her bee collection, she estimates, contains more than 4,000 pinned bees native to the U.S., with about 170 species present.
Out of all of these thousands of bees she – with the help of lab assistants – has pinned, Julianna’s favorite bee is not from Michigan, but, rather, from Arizona.
JULIANNA There are a lot of beautiful bees in Michigan, a lot of metallic green bees that I love, and I love bumblebees. But, in this drawer, I (8:10) have a collection of bees, and also other insects, that I collected while I was in Arizona, at the bee course. This is a course that’s run by the American Museum of Natural History, and I absolutely loved it, it was sort of a overview of how to identify bees to genera, so we went out on collecting trips. And one of the bees that I have here is opalescent. It’s got opalescent bands, it’s called Anomia, and we don’t have it in Michigan. It’s just, it’s got opalescent bands on its abdomen, and, I don’t know, it’s just my favorite bee. When I caught I was just so excited, and, I mean, there are a lot of other cool bees in there, too, but that’s my absolute- that’s my favorite.
ANNA Looking at the cabinet filled with boxes of pinned bees in Julianna’s collection it’s easy to focus on the number, on the thousands and thousands, but Julianna said collecting bees isn’t about numbers so much as about what we can learn from the insects. She said she has mixed feelings about collecting, in that the death of the creatures she loves is an inherent pitfall. But her awareness of the role the bees play in our world and reverence for the things they’ve taught her makes her relationship with the collection complex.
JULIANNA Well, that’s a good question. Because on the one hand, I feel kind of ambivalent about the collection, actually, because I’m – I have to kill a lot of bees to do the work that I’ve been doing. And so, I don’t in general like to just collect insects, because I like to watch them being alive (9:28) and doing what they’re doing in the world. So if I try to kill as few as possible, you know, so like my little collection from Arizona is much smaller than a lot of collections that other people made, and I just, you know, I’m happy with just one specimen, and that’s it. I don’t need a – like a whole run – a string of bees. So, on the one hand I think it’s helping me to get at some really good, interesting questions and answers to questions that we want to know, but on the other hand it’s like ‘Oh, my God, there are so many dead bees’. You know, so I try to take care of them, I feel like I respect what the bees are doing
ANNA Rob Ahern is also a postdoctoral researcher at Michigan State University, and the collection he showed us was remarkably different from Julianna’s. The most common insect in his collection is a minute insect called the Cooley spruce gall adelgid that he has to mount on a slide to get a good look at. Rob described this painstaking process as he sifted through a box of insects on slides
ROB These insects are really small and you actually have to put them onto a microscope slide, and to do that you actually have to go through a process wherein you take all of the fluids out of their body, then you dye them, in this case they’re dyed with a fuchsia dye, and then you lay them flat, and spread their wings and body parts out and then put a cover slip on. These are actually cured in such a way that they’ll stay that way more or less forever. There’s kind of a glue that attaches those two pieces of glass and the insect is smooshed in there, and so hopefully after doing about a dozen of them you get one that you can use to identify the insect, because it’s pretty hard to get these things right.
ANNA Like Julianna, Rob collected the most common insect in his collection for research purposes. He was looking at the variation in one insect species over space – across the Western US and in the Eastern US, where the insect was introduced about 100 years ago – as well as over time. To do this, Rob examines both differences in the DNA of the insects in his collection and their physical variation in characteristics, such as the size of their wings or antennae. He outlines one of the questions he was trying to answer by collecting so many Cooley spruce gall adelgids.
ROB Well, a lot of different studies have shown that glaciers, when they were here tens of thousands or hundreds of thousands of years ago, had a pretty profound effect on the way that insects that are now currently distributed through the Rocky Mountains and the Western United States, how they were isolated from one another and maybe evolved over geologic time. And now that the glaciers have receded, and those populations have moved back into North America, I was interested to see whether or not I could determine remnants of that past fragmentation, either from a genetic standpoint through actually a behavioral standpoint, and now through measuring hundreds of these insects through kind of a morphological standpoint.
ANNA So, while Rob is interested in physical traits of this insect, which can be seen through a microscope, he has also spent a good deal of time working with insect DNA; for this, I picture him using fancy lab equipment in a white coat - not the typical image of an Entomologist. Rob first began actually collecting insects for a college course. Like Julianna, he also “thinks that there are a lot of ways to enjoy insect diversity without necessarily collecting and killing them.” He described to us a greater context he sees his collection fitting into, as well as a broader reason for actually collecting insects.
ROB My collection, my first collection, I made, I believe, in 1996 or 1995, and that’s still the collection that I have, but it’s grown over time. And it’s one of those things that, as somebody who now works in different museum collections, it’s really exciting to pick up a record, or to pick up an insect, and read its tag, and see if it was collected in 1885 or 1886. And it’s one of those things that really is a legacy of people’s effort. And it’s not necessarily the case that my collection will be that way, but it is kind of neat to be part of an endeavor that’s been taking place in the United States at least, for a couple hundred years, and in Europe and in other throughout the world, really for 3 or 400 years, and (13:06) really seeing, going into a museum, and seeing those repositories of species is a neat thing. It’s a neat continuum to be a part of.
ANNA Interestingly, Rob’s collection represents a bit of a history of his relationship with the study of insects, on a shorter timescale than what is represented in museums. When Rob started collecting insects, his interest in insects was very broad, but as he became interested in more specific areas of entomology, like beneficial insects and pests on turf and ornamental plants, his collection has grown deeper, not wider. He said his first collection spanned 120 families while later efforts focused on just a few dozen families or even a single species. As he’s gone through this personal evolution of learning and increasing his specialization in the discipline he’s also found different reasons to get excited about specific insects.
ROB I’ve got kind of a penchant for wasps and things like that, and this particular collection I’ve got a pretty good representative of a kind of a European hornet sort of thing, which I think is- they’re just impressive insects and because they’re usually one of the first things you learn to be afraid of when you’re a kid, to be able to approach them in a box and check them out, I think is pretty neat. But the other ones that I have here, I have an interest in insects that are called scale insects. And they’re really, really small and kind of cryptic, and most people don’t know, don’t even recognize them when they’re around. And I’ve got a collection of some of those, and the reason I like them is because they are almost ubiquitous. They’re on almost any plant, and when you get in to look at them and find those things, it’s kind of like a diamond in the rough, and I enjoy, looking, now some people would just think of it as a collection of sticks and it’s nice to know, you know, that I found those insects, and they’re places where everybody would see them, but nobody would look for them.
ANNA Rob’s interest in both insects that we all notice and insects that many of us pass by without knowing stems not from a childhood fascination with insects, but from an interest in the diversity of life he developed as a child through experiences with aquatic biology.
ROB When I was a kid I lived on an island off of Florida, and I used to go out and go swimming quite frequently. We had a saltwater aquarium in our front hall, and it was kind of a catch as catch can, you’d just put stuff in the aquarium. And that’s, I actually think that that’s how I got into Biology, because I went into the ocean, and swam around, and found all of these really neat things, and put them into the aquarium. And sometimes, one thing would eat everything, you know, and I’d come down the hall in the morning and find that all of the things were dead because I’d put a big crab in there, and it ate everything. And I think that just watching that stuff and collecting these animals and looking at, kind of the cool diversity that there was, even when I was 6 or 7 years old, that was very exciting and really interesting to me.
ANNA The third person we talked to about his collection, Jiri Hulcr, is a PhD student at Michigan State University who studies taxonomy and ecology of bark beetles, which feed just under the bark of freshly dead or dying trees. Most species are less than 1/8 of an inch long. Jiri began collecting insects when he was a child, and describes this passion as something he was born with.
JIRI Well, I guess there are two kinds of collectors: ones that are born with it and collect bugs and frogs and tadpoles from the very start, which is my case, and then there’s the other one, who somehow get to it throughout their career, but I was the freak from childhood. I guess the first really big and interesting semi-professional collection that I made was when my dad put on some giant mercury vapor lamp somewhere and stuck a sheet behind it, and me and my brother, crazy little children, we were running around that for the whole night and it was just cool. I can still remember the moths and the huge Dytiscid beetles and it was cool.
ANNA We asked about whether Jiri’s dad specifically encouraged his children to look at insects, and Jiri told us his father is not an entomologist; he set up this insect collecting rig because he saw his children so interested in insects. Like Rob, Jiri describes a progression in his insect collection that has gotten more specific over time, since the point when every insect within reach became part of his collection.
JIRI I would say there were 3 major steps. One was the one where I was a little kid, when I was collecting every single bug around, mostly the common trash. Then I started to travel around the world, which meant Southeast Asia, it meant Africa, it meant everywhere around, and that’s where I got kind of frenetic a little bit and collected everything and you, now smuggled all of these insects that I was not supposed to smuggle and stuff, and then I kind of grew up a little bit and get to study this professionally, as now, when it’s my occupation, my work. And so I don’t collect everything anymore. I collect specifically only the stuff that’s gonna be important, that I need for my project.
ANNA Jiri’s research project focuses on the diversity of bark beetles in different areas of the tropics. He has a unique method for collecting these beetles: he burns trees, waits 20 days, then comes back to the now bark-beetle infested tree and cuts it up to locate the insects burrowing between the bark and the heartwood of the tree. He explains why cutting trees is necessary for his work:
JIRI So, the reason why I started to burn trees was because when I tried to poison them, when I tried to just cut them down, and tried to do all kinds of things, the burning was really the only thing that kills reliably a tropical tree. And these beetles live in dead wood, in freshly dead wood. And so, thus the burning, because it kills the tree really fast, and then it smells, and it’s most beautiful. You can try it. It’s really like you would like to bite in it because it smells good and the beetles are coming, and then you see the tree is full of sawdust and tiny little holes, which is where the beetles are drilling into the tree. It just works, it’s the best method to attract bark beetles in the tropics.
ANNA We asked Jiri to describe his insect collection to us. This actually required a trip into another room, to a freezer where thousands of insects are stored in tiny vials. This is no ordinary freezer; it’s set to -80 degrees Celsius, instead of the usual -18 that our home freezers run at. This translates to -112 Fahrenheit. At this cold temperature, enzymes are less active and DNA is preserved for a much longer time.
JIRI So, here it is. Here’s our –80 degrees Celsius freezer, which means it’s really, really cold. I probably shouldn’t touch it without gloves. And, as I pull out this one drawer, here they are, all sorted by numbers, little boxes, with lots and lots of little vials. In each of these vials, there are beetles from some strange country somewhere in a (1:01) strange corner of the world.
ANNA What’s the liquid they’re in, even though this freezer is really, really cold?
JIRI That’s pure ethanol. It’s to preserve the beetles, especially their DNA. Actually, this might be called a collection of DNA rather than a collection of insects.
ANNA So, this third collection is not about preserving the insects themselves for others to study and learn from, it’s about preserving their DNA. Like Rob, Jiri is interested in the variation in DNA in the bark beetles he studies, and he uses it to determine how closely related the species are. Jiri is clearly passionate about insects. Another unique aspect of Jiri’s collection, and of his interest in collecting, is that his collection contains insect not just from North America, but from across the globe. There are insects from his childhood home in Europe, from here in the states and from southeast Asia where he does much of his current work. The insects in his collection are tied up in a sense of place, where he collected them, and the ecology of those places.
JAKE Tell us about one insect that you have in your collection and why you had to smuggle it to get it there, and why that was important enough for you to do?
JIRI I think it’s the other way around. It’s that there’s a really cool landscape somewhere, really cool country: forest, desert, anything, and I really want to see that. And when you’re there and you have this disease, called, I don’t know what it’s called, something you just have to collect all of these beetles, then you collect all of these beetles. It’s not that I know that there are these bugs, and therefore I go and collect them and look for them and then am happy when I see them. It’s rather like a sample of the local biota in my Entomology collection box.
ANNA And so when you look at those insects do you think ‘Ah, these are from that place that I went to, and this is what it looked like, and this is how it was to be there’?
JIRI Absolutely. I mean, there (8:08) are people taking photos, there are people collecting stones, and whatever I’m collecting- beetles, mostly- and then, just like you were saying, then I look at it in a few years and I can hear the water, I can smell the forest, I can, you know, be right back there again, sure.
JAKE Thank you for listening to InsectaPod Cast episode 7, Insect Collections. InsectaPod cast is a product of the Michigan State University Dept. of Entomology and is funded in part by the Ray and Bernice Hutson Memorial Entomology Endowment. our home on the web is www.insectapodcast.com. I'm Jake McCarthy, my partner is Anna Fiedler, and this is InsectaPod Cast. We thank you for listening.
