Another fun and rewarding collaboration with Dan Eberl, Olga Miakotina and two amazing students in their Animal Behavior Lab course last fall (2025), Jim and Caleb. This time it was a story about fights between Madagascar hissing cockroaches! Read on by clicking the news title, or read the paper here.

The question in this paper was initially about “Winner’s Effect”, or, whether the recent experience of winning (a fight) makes an animal more likely to win a second one. It turns out there are some tricky experimental design that was not thought through in the beginning (if you chose the winners from a fight and compare them to those who didn’t do a training fight, you can’t distinguish whether any observed difference in winning probability was due to Winner’s Effect or simply selecting stronger animals in the experimental group that have done the training fight. After much discussion and debate, the group found a different angle to analyze the data: taking the videos they recorded of the animals 1 minute prior to and during the “full fight” (to be distinguished from the “training fight”), we found that several “aggressive” and “submissive” behaviors can be used to predict the outcome. That is, we learned we can pick the winner based on how they behave! Also, the data is suggesting although not yet conclusively that having experienced a training fight may increase the probability of the animal winning against a heavier opponent. Pretty cool if this conclusion can be substantiated with more data, although our posthoc power analysis suggests that to show significance at the effect size we are observing, we need to have done >400 fights. That’s how many cockroach lifetime? Oh, well.

Big shout out to our fantastic (former) Biology undergraduate students, Jim Young and Caleb Craven. You guys are the real heros. This is not a simple project and it’s amazing how you were motivated and worked so hard to get this paper done even after graduation and when both of you have day jobs.