Have you ever seen British people dancing abroad? Animals can twist their bodies into all kinds of strange configurations in an effort to attract a partner, and in certain species there is a small line between what is deemed seductive and what is just scary. One such species is the toad-headed agama (Phrynocephalus mystaceus), a lizard that rivals the Demogorgons from Stranger Things.
Such flashes of hue are frequently connected to courting displays (have you seen the small, whirling, blue arms of Carnotaurus?). Agamas can unfold their vibrantly colored cheeks to form a spiky display that resembles a flower with grown-in fangs. However, recent findings reported in the Biological Journal of the Linnean Society imply that these ferocious facial flaps really serve as a warning to predators to flee.
In their research, the authors wrote somewhat poetically that “Conspicuously colored signals may develop via sexual selection to be decorations or weaponry, therefore imparting a fitness benefit to their carrier.”
Contrarily, vivid colors could possibly have evolved through natural selection as [warning] signs or [startle] displays that prevent predator assaults. Conspicuous color patches may develop for one use, such as quality indicators, but they may subsequently be co-opted for another, such as predator defense.
Researchers trapped several agamas in China’s Tukai so they could watch their interactions in arenas in order to learn more about what caused the agamas to flare their cheek flaps. They counted 14 pairs of males and 17 pairs of females, but they saw no cheek activity, indicating that the pairings are not employed to oust rival mates.
Trials between males and females also appeared to show that these cheek flaps had no role in the species’ courting since no one flared their face when there was a lot of tail wagging going on.
Things started to alter, though, when predator pictures were presented. The first thing they saw was a picture of a falcon soaring, which mostly made the animals run away, however 3% of them poked their cheeks out. When they substituted the hawk images for real moving lizards, that proportion increased to 12.
The largest cheek motivator ultimately turned out to be a dental floss attack, as lassoing lizards in an ambush caused 84 percent of those seen to react with what the researchers believe to be a startle show. Because the flaps are hidden when the lizard is at rest, this might work because, should an agama find itself in the grips of a predator, it could be able to frighten them by abruptly changing its appearance.
When picturing an agama unfurling its face before an adversary, a spectacular combat scene from the most recent season of Stranger Things comes to mind, but how effective is it in real life? There is more work to be done, according to the researchers.
More empirical investigations are currently needed to evaluate the deimatic display theory’s predictions and to examine how context affects an animal’s choice to use a deimatic display, they concluded.
“The viewpoint of prospective prey was heavily emphasized in our trials and measurements of anti-predator reactions. The next step is to observe a prospective predator’s reaction to see if the display really does scare it by overwhelming its sensory system.