The Pipevine Caterpillar Thrives in a Toxic Love Triangle | Deep Look

From Deep Look.

The devilish caterpillars of the pipevine swallowtail butterfly *devour* the California pipevine, never mind that the plant is trying to poison them. Their butterfly moms don’t pollinate the pipevine in return, though. So, the vine traps unlucky gnats in its labyrinthine flowers to do the job.

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This is the story of a love triangle between a plant, a striking butterfly and an intrepid gnat. At the center of this triangle is the California pipevine (Aristolochia californica). The plant produces poisonous compounds called aristolochic acids and it’s also known as the California Dutchman’s pipe because its flowers are shaped like a tobacco pipe.

The California pipevine swallowtail butterfly (Battus philenor hirsuta) loves the vine. It flutters around the plant with its bright blue and orange wings and lays clusters of eggs on leaves and stems. When they hatch, the caterpillars feed exclusively on the pipevine. But the butterflies don’t pollinate the plant. Instead, the pipevine lures fungus gnats into its flowers with a mushroomy aroma that reminds the flies of the fungi they feed on in the soil as larvae. The flies get stuck inside the curved flowers long enough for their hairs to get coated in pollen. This strategy in which a plant attracts pollinators under false pretenses is called deceptive pollination.

— Is the California pipevine a native plant?
Yes, it’s the only pipevine native to the state. It grows naturally along rivers.

— Are fungus gnats considered pests?
Yes, they are. The adult flies lay their eggs in the earth, where their larvae feed on fungi and plant matter. If they get into potted soil, they can chew on the roots of houseplants and damage them.

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—+ Shoutout!

Good try everyone! No-one got our GIF challenge correct for this episode. The caterpillars feeding side by side helps them grow bigger faster. The faster they grow, the better protected they are because they accumulate toxins in their bodies as they feed on the California pipevine.

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#californiapipevine #gnats #deeplook