Sugar‑Driven Backflips Power Manakin Courtship Displays

Manakins move with such speed that they often appear as fleeting blue or red blurs across the rainforest floor of South and Central America. Males, renowned for elaborate courtship displays, snap their wings, circle rivals, and execute backflips to attract mates.

What fuels their energy? Prior research indicates manakins have fast‑twitch muscles and hearts capable of brief, intense activity bursts. Recent genetic work suggests these traits evolved after a key dietary shift: the ability to detect and digest sugary fruits preceded their energetic dancing.

“This is a remarkable aspect of the study,” said Maude Baldwin, an evolutionary biologist at the Max Planck Institute for Biological Intelligence in Germany and a co‑author of the paper published on June 10 in *Current Biology*. “We were able to explore the evolutionary history of the birds’ relationship with fruit.”

More than two decades ago, the first bird genome was sequenced from a wild red junglefowl, providing researchers with an unprecedented view of avian genetics and insights into how birds perceive their environment. Notably, red junglefowl lacked a taste‑receptor gene that earlier birds used to detect sweet flavors — a gene that persists in mammals.

Later studies on other species showed that birds lost the sweet‑taste receptor during the dinosaur era, rendering them ancestrally insensitive to sweetness, Dr. Baldwin noted. Nevertheless, certain fruit‑ and nectar‑feeding birds evolved to perceive plant sugars by repurposing the mammalian umami taste receptor.

The recent study sequenced the genomes of five manakin species, confirming that these birds can both taste and readily digest fruit sugars, thereby securing the energy required for their spectacular displays.

“This made me realize that feeding is not just about nutrient intake; it can also drive the emergence of biodiversity,” said Yasuka Toda, a food scientist at Meiji University in Japan and a study co‑author.

To establish this diet‑behavior link, researchers compared genomes of species that diverged from the common manakin ancestor at various times, allowing them to reconstruct the sequence of physiological and behavioral trait evolution.

Even before evolving a sweet‑taste receptor via the umami pathway, manakins acquired a gene modification also present in humans for lactose digestion. Researchers hypothesize that this gene helps birds neutralize harmful natural toxins or indigestible fruit compounds. Only subsequently did they acquire genes supporting energetic dance routines and vivid ornamentation, presumably enabled by a calorie‑rich diet.

“We have been working in the genomics era for some time, yet obtaining high‑quality genomic data remains challenging,” noted Sushma Reddy, an evolutionary biologist and ornithologist at the University of Minnesota, who was not involved in the study. “Thus, this study is exceptionally valuable because it links genomic data to concrete traits.”

The authors hope their interdisciplinary approach will motivate other researchers to discover new information about manakins and other bird species.

“We uncover countless hidden surprises and insights from the genomes of diverse organisms,” Dr. Baldwin remarked. “Evolution has devised countless solutions and mechanisms, of which we have only observed a fraction.”

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