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Happy to share our new @PNASnews paper, a multi-national team effort led by @JPLawrencePhoto aiming to understand how variation in warning signals can persist, and providing new perspectives on frogs' chemical defences (⚠️: toxicity≠unpalatability!) (1/n) pnas.org/content/early/…
@PNASNews @JPLawrencePhoto In two populations of dyeing poison frogs displaying the same pattern but different colour, we deployed an army of clay models to test the reaction of wild predators to known and novel colour patterns. (2/n) #colsci 
@PNASNews @JPLawrencePhoto We expected that local colour patterns were less attacked by wild predators, but that was not the case in either population. We moved on to test if maybe one of these colours (white, yellow) was inherently easier to learn to avoid. So we tested that in the lab using chicks (3/n)
@PNASNews @JPLawrencePhoto Chicks learned to avoid yellow faster than white, especially when it was associated with high unpalatability. Once they learned to avoid yellow, they transferred this aversion to white, but not vice versa! So we wanted to know if wild yellow frogs were more unpalatable (4/n)
@PNASNews @JPLawrencePhoto We analised skin extracts of both pops and found that the white one has a higher amount of alkaloids than the yellow pop... But what does this mean for a predator? Previously, toxins have been injected into mice... but, in nature, toxins are ingested rather than injected! (5/n)
@PNASNews @JPLawrencePhoto So we used a novel method to test how avian predators would react to the *taste* of the frogs' skin secretions when presented on oat flakes... Despite their lower amounts of alkaloids, the secretions of yellow frogs were more unpalatable for the 🐦 (they hated them 👇)! 6/n
@PNASNews @JPLawrencePhoto To sum up, yellow seems to be a better signal, and the yellow pop seems to be better protected chemically. White is more attacked in the field, more difficult to learn, and this population doesn't seem to have very predator-deterrent defences... How/why does it exist? (7/n)
@PNASNews @JPLawrencePhoto We think that the lack of gene flow, as is the case between these 2 pops, is key. After all, the white population can still get *some* protection from predators with what it has, but it would probably be hard for it to thrive if yellow individuals started to invade. (8/10)
@PNASNews @JPLawrencePhoto It was great to work with this amazing group of scientists, thanks to y'all! @JPLawrencePhoto @bricenoonan @JohannaMappes @BasicBiologist et al. (9/10)
@PNASNews @JPLawrencePhoto @bricenoonan @JohannaMappes @BasicBiologist Finally, if you are rather looking for a lay version of our study, have a look at what the talented @drstevilphd wrote about it 👉 "Survival of the weaker" (10/10) drstevilphd.com/blog/2019/9/3/…
