Previous: Zebra Bits
Next: Insect Adventure, Part Two



View count:115,698
Last sync:2024-04-28 11:30


Citation formatting is not guaranteed to be accurate.
MLA Full: "Insect Adventure, Part One." YouTube, uploaded by thebrainscoop, 30 October 2013,
MLA Inline: (thebrainscoop, 2013)
APA Full: thebrainscoop. (2013, October 30). Insect Adventure, Part One [Video]. YouTube.
APA Inline: (thebrainscoop, 2013)
Chicago Full: thebrainscoop, "Insect Adventure, Part One.", October 30, 2013, YouTube, 09:50,
Nothing says collection expedition like rotten chicken liver!

Help the Jo Daviess Conservation Foundation restore more native prairies in Illinois:


The Brain Scoop is written and hosted by:
Emily Graslie

Special Guests and huge thanks to:
Jim Louderman and Rebekah Shuman Baquiran, Assistant Collections Managers of Insects

Created By:
Hank Green

Directed, Edited, Animated, and Scored by:
Michael Aranda .

Filmed on Location in Hanover, IL
and Supported by:
The Field Museum in Chicago, IL

Photo credits:
THANK YOU to Derek Hennen ( for supplying many of the images of millipedes in this video.

Mark Wetmore (Necrophorus marginatus)

Michael K. Oliver, Ph.D. : (Necrophila americana)

Spirostreptid photo from (

Marshal Hedin (Platydesmida)

Joseph Berger (Polyxenida: Polyxenus lagurus)

(Polyzoniida: Octoglena bivirgata) (

Thanks to Rosa McGuire, Katerina Idrik, Tony Chu, Seth Bergenholtz, Anne-Sophie Caron, and Kelleen Browning for translating captions!
[Intro music]

Jim: Okay we're here today because the town of Hanover and Jo Daviess Conservation Foundation have acquired this old soy bean field, and they're restoring it as a prairie, and they've been working here for about six years, and we're surveying the insect population. Okay, so this is a carrion trap.

Emily: Eww.     

Woman: Ooh lots of good stuff.

Emily: Wow

Jim: So, we here's lots of stuff in here.

Emily: So how long was this in the ground for?

Jim: Four and a half weeks

Emily: Really

Jim: About a month. 

Emily: And that's a tea strainer, that you're going to strain though. 

Jim: That's a tea strainer

Emily: That's very sophisticated

Jim: Yeah, we are.

Emily: (laughter) So it's a carrion trap, so what does that mean?

Jim: Okay, so this, had four ounces of chicken liver in it.

Emily: Sounds appetizing.

Jim: Hung over the bucket. And the carrion trap they're compelled by the rotting meat smell and fall in, and there's

Emily: What is it, those look like a lot of millipedes

Jim: Those are millipedes, yeah

Emily: Tonnes of millipedes

Jim: A bunch of millipedes in here, bunch of grasshoppers

Emily: Those are some huge grasshoppers.

Jim: Yeah, this is one of the carrion beetles,  Necrophilia Americana

Emily: It's kinda cool looking

Jim: So that's, it's one of the carrion beetles that we find here, it's really hard to tell what you've got until you get back to the museum and put it under the scope. 

Emily: Yeah, and identify a lot of the smaller ones. 

Jim: Yeah and then you identify a lot of the smaller stuff, lots of isopods, rolly polies.

Emily: Yeah, lots of different kinds of millipedes. How many different species of millipedes do you think are out here? 

Jim: Out here in this prairie? Between fifteen and twenty.

Emily: Really, I didn't know there were that many.

Jim: There are at least six different orders of millipedes out here, Polydesmids, Spirobolids, Spirostreptids, Julids, Platydesmids, Polyxenidas and possibly Polyzonidas.

Emily: So what does that mean? They have like different numbers of legs or different numbers of body segments or? 

Jim: They have different numbers of legs, different numbers of body segments, uh, the reproductive organs are in different places on the body.

Emily: Oh they're not just at like where you would assume, like, the genitals to be.

Jim: No, some of them the male genitals are on the second segment, some of them are on the seventh, some of them are on the eighth.

Emily: So the second segment like on the neck

Jim: Just right behind the neck

Emily: So you have gonads like on your head

Jim: Yeah, they call them gonopods in millipedes. So they are right behind, and they are on the underside, on the belly, right behind the head or a few segments further down or a few segments further down. 

Emily: Okay.

Jim: And the females all have different types of ahh, genitalia as well.

Emily: Well you got to correspond to having gonads on your neck

Jim: Yeah. (laughter) Then you just put the bucket back in the ground, and this is just propylene glycol.

Emily: So you don't want to use alcohol out here because it will evaporate.

Jim: It will evaporate away. So you

Emily: And so you use that.

Jim: use propylene glycol which is not toxic to mammals, so if a raccoon gets in and drinks the fluid it won't hurt them. This is fifty percent propylene glycol, fifty percent water and a couple of ounces of liquid dish soap, and the dish soap breaks the surface tension.

Emily: Okay

Jim: So when the insects fall in they sink   

Emily: Yeah instead of

Jim: They don't just float, because if they floated in a couple of hours the surface would be covered with insects, other ones would land and just fly away.   

Emily: Ooh, I see.

Jim: So they fall in, they sink and they just keep falling in and sinking. Now here is the part that's so much fun for you. This is chicken liver, wrapped in gauze, tied up.

Emily: How long has this chicken liver been sitting out? 

Jim: About two and a half days at room temperature, so it's starting to smell pretty good.

Emily: Oh, hmm.  

Jim: Isn't the appetizing?

Emily: It's nice and fragrant, yeah.

Jim: So then you just hang that over the bucket and the smell of the rotting chicken liver attracts all those carrion eating beetles, they fall in the bucket and sink down to the bottom.  

Emily: So why are you specifically trying to get carrion beetles? 

Jim: A lot of other things will fall in as well, some of the beetles that are attracted to carrion are considered habitat indicators, one of the carrion beetles called Nicrophorus marginatus, that's only found in fairly high quality prairies, the last set of traps that we set had Nicrophorus marginatus in it, they also had a scarab called Phanaeus vindex which is a dung roller that is also only found in high quality prairies.

Emily: So six years ago there where soy beans here and now you've got a nice healthy prairie. 

Jim: Yeah

Emily: So when you get a healthy prairie and you have all these good bugs as good indicators of how healthy the prairie is, that's going to obviously attract birds and mammals and all kind of things to come back to this area that maybe hadn't been here for years.

Jim: If you've got good insect, you get more reptiles and amphibians, you get more birds, you get more birds more reptiles, amphibians, you get more mammals and the populations and the community just keeps building and building over the years.

Emily: This is exciting.

Jim: So now we've got three or four pit fall traps  

Emily: Okay

Jim: Which are the same thing but without the bait. Occasionally a mouse or something will fall in and it can't get out, but then we take it to the mammal division at the museum

Emily: Oh yeah.

Jim: And it goes into their collections, and then they have records of them being here 

Emily: Yeah 

Jim: So nothing ever goes to waste. And there's some beetles too,

Emily: Wow, some grasshoppers.

Jim: Carabid beetles, that's a ground beetle a Carabid beetle

Emily: Some spiders in there

Jim: Yeah, there's spiders and you don't usually find very many spiders in carrion traps because most spiders are actually repulsed by the smell of carrion.

Emily: Really?

Jim: So spiders walk up close to a carrion trap and then veer away

Emily: Oh that's interesting, I would have thought that everything would just, you know, swarm to the stink smell. 

Jim: There are a lot of beetles that are repulsed by the smell of carrion also, so they fall into these kind of traps 

Emily: So you've got to make sure you have diverse, different ways of collecting everything.

Jim: The more ways you have of collecting, the more different types of insects you're going to find. So far we've collected eight hundred spiders and insects at this point.

Emily: Wow.

Jim: Just over the same period of four weeks.

Emily: Eight hundred different species in four weeks.

Jim: In four weeks, yes. We could easily find twelve to fifteen hundred over a full summer. So we should get a whole lot more than what we have so far.   

Emily: That's exciting, I can see why you'd really get into this. This seems relatively low technology. 

Jim: It is really very low cost, low technology and basically anybody can do it, you can go to the, uh, car parts store and get a little bit of propylene glycol, put the holes in the ground.

Emily: You just need some dish soap   

Jim: Some dish soap and water

Emily: Some old railroad spikes    

Jim: and to do the carrion trap, a little bit of chicken liver. You can set a full set of traps for fifteen bucks, and then some alcohol, some rubbing alcohol to put them in.   

Come on, start. We're going to go back right in there between those trees, and string the line.

Emily: It's beautiful back here

Jim: It is a cool place

Emily: Yeah, just gorgeous. Have you set up a sheet back here before?    

Jim: Yeah, I have and if the weather is good it does pretty well. If the weather is too cold, it doesn't do anything. Okay, bring it back around again, you have to have one to hang the sheet from and one to hang the light from.

Emily: Oh that makes sense. How long have you been doing this? Like how long have you been going out into the field collecting bugs?

Jim: Seventeen, eighteen years now. I collect live things and bring them home and watch them, I watch caterpillars eat and grow, and spin their cocoons, wait for them to emerge and whenever they came out. You know there's an old saying "If you love what you do, you'll never work another day in your life". I get a paycheck every other week but I haven't worked in eighteen years, for me it's great fun and I get paid for it, I get paid for my hobby what could be better. This will hold it down and keep the sheet from blowing     

Emily: Oh there is a spider.

Jim: This is a mercury halide light, 250 watt bulb and that gets hung up here.

[Music plays]

[Outro music]

Emily: It still has brains on it.