Plastic wrap and a plastic cup have taken the place of an egg in new research that reports that chickens can be grown outside of their eggshells.

Baby chickens-to-be spent their first 55 hours or so incubated in their eggs— which had been purchased from a grocery store in Japan— and then were transferred to an artificial vessel for the rest of their growth, a research note in the Japan Poultry Science Association explains.

Later, pure oxygen was added to help the chicks grow, a factor that led to a “hatchability” rate of 57 percent, the study reports. The research note concludes by saying that the method is still being perfected and that the system could ultimately have implications for raising transgenic chickens and doing other research.

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What’s more, the work was carried out by high school students.

“The teens cannot contain their excitement when by day 3, they discover that inside of the yolk is a beating heart,” the New York Post reports, describing a video of the research that had been posted to YouTube and has since been removed.

“After a week, the students are able to see the formation of veins around the yolk,” the Post adds.

And eventually, voila: “The video then shows the fluffy baby chick happily running around the classroom.”

In other words, the eggs may have come first, but they weren’t needed for long.