Naturalist Selections is an interview series produced by the American Society of Naturalists Graduate Council. We showcase graduate student and postdoc authored work in The American Naturalist, a premier peer-reviewed journal for ecology, evolution, and animal behavior research. Catch up on exciting new papers you may have missed from the journal, and meet some truly brilliant early career naturalists!

In this episode, Basabi Bagchi chats with us about new paper Bagchi et al. 2022: ‘Carcass Scavenging Relaxes Chemical-Driven Female Interference Competition in Flour Beetles.’ We talk about the difficult life of a female flour beetle: toxins, cannibalism, disease, the usual. Clearly, a bag of wheat is not the paradise you think it would be! But all is not lost – it turns out that a female beetle’s behavior can affect not only her own fitness, but also that of her group mates. You can read Basabi’s full paper here: https://www.journals.uchicago.edu/doi/10.1086/717250.

Hungry for more beetle talk? Email Basabi at basabi.bagchi_phd17@ashoka.edu.in!

<figure class="wp-block-audio"></figure>

Listen on Spotify and Apple Podcasts!

Credits

Featured Guest: Basabi Bagchi, Ashoka University, India

Host, Editor, Producer: Sarah McPeek, University of Virginia, US

Original Music: Daniel Nondorf, University of Virginia, US

Transcript:

You’re listening to Naturalist Selections, an interview series featuring graduate student and postdoc-authored work in The American Naturalist, produced by the American Society of Naturalists Graduate Council. Today we talk with graduate student first-author Basabi Bagchi about her new paper ‘Carcass Scavenging Relaxes Chemical-Driven Female Interference Competition in Flour Beetles.’ Basabi is a PhD candidate with Dr. Imroze Khan at Ashoka University in India. Basabi and her labmates study how behavior can mediate the negative consequences of crowded living conditions in the flour beetle Tribolium castaneum. When many female flour beetles share few mating and food resources, they produce toxic chemical secretions that reduce each other’s egg production. So what’s a female flour beetle to do? In a series of detailed experiments, Basabi and her lab mates investigate how females may overcome these negative effects. Interestingly, they find that females don’t move away from crowded areas. Instead, females can improve their fecundity by scavenging the carcasses of larvae for added nutrition. Females feeding on carcasses also produce fewer noxious chemicals than females who only eat wheat. Hence, an individual female’s behavior could help mitigate costs that affect her whole group. I spoke to Basabi to enrich my understanding of these fascinating behaviors.

Sarah

I’ve read so much about these flour beetles because they’re such a classic system to work with for all these kinds of behavioral questions. I’m really curious what your setup looks like and what you observe when you’re watching the beetles foraging and interacting with each other.

Basabi

Okay, so these are quite tiny to begin with. The thing with these beetles is they live where they eat, basically. So these are actually maintained in boxes or jars or whatever sort of setup that you want to have. It could be a box, it could be a jar and that is essentially filled with the wheat flour which they live on. So you have a bunch of beetles, you sort of give them just put them together in a boxand you let them lay eggs and once they lay the eggs you have this sort of a strainer sort of thing where you’ll to strain these beetles out. And this flour which passes through the sieve which has the eggs, this goes for incubation. Now the beetles that I work with are the populations that I work with. They have a 35 day discrete cycle and these are holometabolous which means that they have different life stages. So start with egg, then they have larvae per adult. So at the pupil stage we basically collect the beetles, we sex them and we store them in these plates which are 96 well plates. Now, 96 well plate is something which is very known to people who work with molecular biology but we use them to store beetles actually. And each well houses one pupa. Yeah. So we have a 96 well plate which has 96 pupa in it and then we give them this time to mature sexually for two weeks. And for us because we are working with carcasses, we had this period where we had to generate the carcass. So for them we use larger carcasses. So in between this maturing period we had to give another set of egg laying to generate our carcasses. And because the beetles were sexed previously we just had to sort of put them into different sex ratio treatments like male biased female bias that’s there in the paper. And we added the carcasses which were sacrificed on the day of the experiment primarily. But what I’d like to mention is because we had these sex ratio treatments, what was exciting or what we had to do before doing all of this is prepare the plates. So what we used was essentially 35 millimeter plates which is a small place and these were previously filled with flour. We had to Mark them even if you had the experiment today. So these sort of preparations needed to be done like three, four days before the experiment. Sure, because as the setups are really big so they take up almost the whole day. once you set the experiment it’s pretty fast. It’s about a ten day experiment and then you have most of your results by end of ten to 15 days.

Sarah

That’s pretty nice. So fast and very small. Weird question. Are you a baker at all?

Basabi

Yeah, I do like to bake.

Sarah

You do! I feel like the process of sifting the flour together, the beetles out is very much like what you do when you’re baking.

Basabi

Yeah, I didn’t fit that way. I mean it’s a good correlation actually. But Incidentally, I do like to bake. I love sweets, so I like making them too. Yeah, I mean I didn’t think of it that way actually. That’s a good point.

Sarah

I do want to ask you about the chemicals in the beetles. Is it quinones?

Basabi

Quinones.

Sarah

Quinones. Okay, I am saying that right. So these quinones that the beetles are releasing. The paper describes them as being from stink glands?

Basabi

Yes.

Sarah

Do they smell. Can you smell them?

Basabi

Yes, you do smell. Yes, they do smell. When you have a population, like I said, in a box, and that population is very crowded, the flour sort of turns a little pinkish, and you have a very pungent smell, which is there in the flour. And when you’re looking at them individually, when they first secrete these chemicals, they look yellow, and with time, they turn the flour pink, actually pinkish tinge to the flour. So the box also smells quite pungent. Interestingly, my advisor. So we have a prelude to this paper. So the previous AmNat paper where actually the work where they show that chemical interference is happening in these beetles? That’s how my advisor actually found out that quinones are playing a role, so he could smell that in the flour, and that’