Alex Trillo

Collateral Damage: Being next to an attractive
signaler increases risk of attracting parasitic midges

Contributed by Alex Trillo @Trillo_PA


Animals, Behavior, Biome, Central America, Communication, Competition, Conservation, Consumption, Ecology, Field, Immigrant, Indirect, Latino/a/x, Natural history, Race/ethnicity, Terrestrial, Woman



Note: click the gear symbol to see notes that accompany the presentation

View and download in google slides here



Trillo, P.A., Bernal, X.E., Caldwell, M.S., Halfwerk, W.H., Wessel, M.O. and Page, R.A., 2016. Collateral damage or a shadow of safety? The effects of signalling heterospecific neighbours on the risks of parasitism and predation. Proceedings of the Royal Society B: Biological Sciences, 283(1831), p.20160343. link



Slide 1: Researcher’s Background

Alex is a behavioral ecologist at Gettysburg College and she studies the effect of eavesdropping predators and parasites on frogs mating signals

PB: Why did you become a biologist?

AT: I have always loved animals and being outdoors – I found a way to make it my job


PB: What is your favorite part about your job?

AT: Being in the forest and watching animals behave! I also love teaching field courses


PB: What obstacles have you overcome to get where you are?

AT: The most obvious ones might have been not knowing much English when I first moved to the US (I am from Perú). People still make fun of me at meetings and classrooms because of my accent. I don’t get taken as seriously. The second one was having children at the end of graduate school, and then as faculty. I was told both times I would not make it with children in Academia. The third one was staying in Academia at times when my family needed monetary support and I could not afford it. This was especially hard when I was in between jobs and did not have money myself. There are many smaller compounding obstacles though, and when you add them all up, they can really make a number on you.


PB: What advice do you have for aspiring biologists?


  1. Find your tribe, the support group of friends who understands academia and who you can talk to when things are hard or unfair. 
  2. Find your sponsor, your academic ‘Auntie’ or ‘Uncle’ who will be there to support you and guide you through the tough times. 
  3. Give yourself grace……rest when you need to, this is a marathon, not a sprint.  Don’t forget why you chose this path! If it is nature, then keep getting outdoors! If it is the lab, then go put some music on and do the lab work you like.

PB: Do you feel that any dimension of your identity is invisible or under-represented/marginalized in STEM?

AT: Yes. I am a Latinx scientist, immigrant, in the Sciences. I do not have many role models because there aren’t that many people like me in Animal Behavior. In fact, as of 2019, there were only 5 Women Latin American scientists with a faculty position in Animal Behavior.


Slide 2: Research Overview

Take home message of study

In mixed-species aggregations of frogs, calling next to an individual of a species that is highly attractive to parasitic midges (túngara frogs) increases the risk of parasitism for an individual of a less attractive species (hourglass treefrogs). The risk of producing a mating call doesn’t only depend on how attractive your call is to predators and parasites, but also on how attractive are the calls of your neighbors.

Study system

Species included are Túngara frog (first photo, Engystomops pustulosus), Hourglass treefrog (second photo, Dendropsophus ebraccatus), and Frog-biting midges (third photo, several species within the Corethrella genus). These midges bite the frogs and collect blood meals from them. Cost of these midges is not only the blood meal but possibility for transfer of Trypanosomes.


Slide 3: Key Research Points

Main figure

The figure shows the number of midges attracted to a speaker playing an hourglass treefrog call when this call is playing alone (first bar, H), when this call is playing next to another speaker with an hourglass treefrog call (second bar, H+H), and when the call is playing next to another speaker with a túngara frog call (third bar, HT). The number of midges attracted to the speaker increases threefold when an hourglass treefrog is next to a túngara frog (HT) compared to calling next to conspecific (H+H) or calling alone (H). 


Societal Relevance

This process might apply to other species that are endangered. If endangered species experience collateral damage because they call next to other species attractive to predators, this might influence their likelihood of survival and persistence in mixed-species choruses. Information like this might be relevant for species reintroductions, and any efforts to save rare species.

Leave a Reply

%d bloggers like this: