The famous Monarch butterfly eats milkweed leaves as a caterpillar and drinks its nectar as an adult. High enough levels of milkweed sap can be toxic. How, then, do their predators survive?
To be able to eat this plant, monarchs evolved a set of unusual cellular mutations. New UC Riverside research shows the animals that prey on monarchs also evolved these same mutations.
A Current Biology journal article, published today, describes the research that revealed these mutations in four types of monarch predators — a bird, a mouse, a parasitic wasp, and a worm.
“It’s remarkable that concurrent evolution occurred at the molecular level in all these animals,” said UCR evolutionary biologist and study lead Simon “Niels” Groen. “Plant toxins caused evolutionary changes across at least three levels of the food chain!”University of California – Riverside, “How to eat a poison butterfly” at ScienceDaily (November 22, 2021) The paper is closed access.
Eric Cassell on the mystery of Monarch butterfly migration. There exists no evolutionary model that satisfactorily explains its origin. That by itself does not prove that gradual evolution didn’t produce such programming, but the lack of such a model should at least give the open-minded pause for reflection.
Caterpillar on milkweed, moulting skin: