If Termites Wore Stripes, Would Spiders Still Eat Them?
The animal kingdom is filled with colors and patterns. Sometimes, those colors are to signal to members of an animal’s own species, in a mating display for instance. In other cases, a bright color or vibrant pattern serves as a warning to potential predators—a signal saying “don’t eat me, I’m toxic.” That type of warning coloration, known as aposematism, can be seen in the bright colors of a poison dart frog, or the black, white, and yellow stripes of a monarch butterfly caterpillar.
Bigger animals, like birds, are known to consider that sort of warning signal when hunting. Researchers at the University of Florida were interested in whether jumping spiders might also take that sort of striped warning coloration into account when choosing their prey. To find out, they applied tiny striped capes to the backs of laboratory termites to study whether those stripes affected the behavior of hungry jumping spiders. They found that while the test spiders did notice the striped termites more than termites wearing solid colors, the spiders were less likely to attack striped termites when given the chance to do so.
Behavioral ecologist Dr. Lisa Taylor joins Ira to discuss the purpose of the project—and former lead undergraduate researcher Lauren Gawel describes the challenges of trying to get termites to dress up as superheroes.
Dr Lisa Taylor is a behavioral ecologist in the Entomology and Nematology Department at the University of Florida in Gainesville, Florida.
Lauren Gawel is a veterinary intern in the Tufts Cummings School of Veterinary Medicine in Boston, Massachusetts.
IRA FLATOW: Our next story is about putting tiny capes on the back of termites. Now, I know this sounds a bit crazy, but stay with me on this, OK? Scientists are trying to decode the importance of signals, like colors and patterns, in the animal kingdom.
So let’s say you’re a spider, a fuzzy jumping spider, looking for a meal. Which succulent termite, let’s say, looks the tastiest? Researchers at the University of Florida turned to applying tiny striped capes to the backs of termites to study how those stripes affected the behavior of hungry jumping spiders.
That’s the premise. Here’s the explanation presented by Dr. Lisa Taylor, behavioral ecologist in the Entomology and Nematology Department University of Florida in Gainesville, and Dr. Lauren Gawel, the lead undergraduate researcher on this project, who is now a veterinary intern in the Tufts Cummings School of Veterinary Medicine. Welcome both of you to Science Friday.
LISA TAYLOR: Thanks for having us.
LAUREN GAWEL: Thanks. I’m really excited.
IRA FLATOW: And nice to have you. OK, Lauren, why put a cape on a termite?
LAUREN GAWEL: Besides the fact that it’s absolutely adorable, in order to do this study, we were looking at if these jumping spiders would have the same reactions to what we call aposematic patterns in the wild or aposematic displays.
IRA FLATOW: So by aposematic, you mean it’s a warning symbol to predators.
LAUREN GAWEL: Exactly. Something like the color red is one that we think of a lot in the wild, where an animal will see the color red and think danger. I should not eat that. I should go turn the other way. Black and white is another one of those things, so if you think of a skunk, you definitely don’t want to mess what’s one of those.
And those colorations are kind of a big glaring way to get your attention and make sure that you know that right off the bat. So we wanted to test that sort of display in spiders. Their best prey that we could give them in the lab is termites, which don’t necessarily have any of these colorations naturally. And so in order to provide different colorations in a controlled setting, what’s been done in the past and what we did for our study is to put little paper patterned capes onto them.
IRA FLATOW: Dr. Taylor, you study colors as communication and signals in spiders and other species. What is this telling you?
LISA TAYLOR: Yeah, so we can learn a lot from these experiments because, if we just go out in the natural world, you see all these colors and patterns. And for me anyway, it just makes me wonder like, what is this all about? What are all these colors and patterns doing?
And we’ve learned a lot from these types of experiments with birds, for example, where a lot of things we’ve learned so far suggests that there are certain colors and patterns that are just really good at warning of toxicity, like red and black and white stripes. These things kind of jump out to predators, are really obvious. And so predators either have innate aversions to these colors and patterns, or they can easily remember these colors and patterns. So if they attack something that’s red or black and white striped and it tastes bad, those colors and patterns are really memorable.
And so I’ve just always been really interested in trying to understand why animals have all these colors and patterns and why they work, why some work better than others, and what predators are directed towards. So we know that a lot of them are effective with birds. But we know a lot less about other predators that are really common out there, like these tiny jumping spiders.
IRA FLATOW: Very interesting. Now, Lauren, I have to ask you, how do you put a cape on a termite? And don’t tell me, very difficultly.
LAUREN GAWEL: How is, very carefully, then? So the actual process, there’s a little bit of trial and error. Not going to lie, some termites were sacrificed for the greater good of me figuring out the best way to do this. But literally, I just took the smallest drop of Elmer’s glue possible, and put it on this little paper cape, and figured out the best amount of force to lay it on top of the termite’s back for it to stick, and not squish the poor little termite, and not overwhelm it completely with too much glue. I eventually figured out the right ratio for the glue and the amount of force and placed many, many, many of those capes.
IRA FLATOW: Dr. Taylor, can you give me some examples of insects that have these warning stripes when they’re not wearing tiny glued-on capes?
LISA TAYLOR: Yeah, yes, so these are really common in nature. So stripes in particular, some of the most common things you might think of are like monarch caterpillars. So they’re black and white stripes, and they also have a little bit of yellow. There’s a lot of caterpillars that have black and white stripes.
A lot of butterflies and moths have black and white striping on them. That’s pretty obvious to predators. And those are relatively very large insects, so those are probably trying to communicate with larger animals like birds.
So what I think is really interesting is there’s a lot of really, really tiny insects that have black and white stripes. The tiniest little baby monarch caterpillars are a good example, but then also there’s these little treehoppers that have black and white stripes. There’s some little plant hoppers that have black and white stripes.
And there’s even this really cool insect called the harlequin bug that lays these really tiny black and white striped eggs that are thought to be chemically defended. And so all those things we think are warning that they’re toxic. But they’re really tiny, so they’re probably not warning birds. They’re probably warning something smaller, like jumping spiders.
IRA FLATOW: Wow. OK, so Lauren, drumroll please. What happened? Did the stripes make the termites unattractive to the spiders?
LAUREN GAWEL: Yeah. So ultimately, the stripes are bold, and brash, and attention getting. So in the first part of our study, we did find that the spiders oriented to or kind of faced and looked at the termites with the black and white striped capes first. And then when they were allowed into the same area as the termites, despite the fact that they had oriented to those striped caped termites first, they often decided not to attack those and to attack one of the solid-colored caped termites instead.
IRA FLATOW: Dr. Taylor, what would you need to take this further? If you had a blank check, which, of course, I have for you, what would you do?
LISA TAYLOR: Well, we’re really excited that you have a blank check for us. That sounds great.
IRA FLATOW: It’s in the mail.
LISA TAYLOR: One thing that I think would be really fun would be– with a blank check, would be to create the equivalent of really tiny GoPros to put on these spiders and GPS trackers because we can do all these really interesting experiments in the lab and understand how they make decisions in these different contexts that we put them in. But I would really love to just be able to see more like what their world is like in the field.
We catch these spiders in the field, and we’ve tracked them. We can track them pretty easily. But they’ll dart under the leaf litter and hide from us occasionally. So I’d really like to know where they go, how many other spiders they encounter, what the possible prey items are that they encounter, where they sleep, and just kind of what the day in the life of a jumping spider is.
IRA FLATOW: All good questions, and I want to Thank both of you. We’ve run out of time. Dr. Lisa Taylor, behavioral ecologist in the Entomology and Nematology Department. That’s at the University of Florida. And Lauren Gawel, she was the lead undergraduate researcher on the project but is now a veterinary intern in the Tufts Cummings School of Veterinary Medicine. Thank you both for taking time to be with us today.
LISA TAYLOR: Thanks for having us. It was fun.
LAUREN GAWEL: Thank you so much. This was great.