An aphid and fungus are linked by a DNA strand. This DNA is responsible for producing carotenoids.
Long ago, an ancestor to today's pea aphid somehow internalized a large important chunk of DNA from a fungus. This DNA now allows the aphid to generate its own carotenoid molecules. All animals need carotenoids for body functions as important as eyesight. However this aphid is the only organism in the Animal Kingdom so far to have been reported capable of producing it internally. The rest of us must forage for foods such as carrots, containing carotenoids. The precise way the DNA transfer occurred is not yet understood; however patterns within the DNA conclusively show a link to a fungus. DNA transfer from fungus to animal is unprecedented.
Credit: Zina Deretsky, National Science Foundation
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