A video on Facebook claiming to show a slice of genetically modified tomato 'swimming' in salt water due to a 'fish gene effect' has been shared thousands of times. Some versions of the video feature a second clip showing genetically modified wheat doing something similar. The clip of wheat is also circulating as a separate video too.
The caption of one post says: "Here is a way to test your fruit and veggies if they are GMO. GMO plants swim on their own in salt water!"
Genetically modified plants don't 'swim' in salt water. The videos originate from a YouTube channel called ViralVideoLab that publishes clips edited with CGI. The channel's about page says it features "videos that seem too impossible to be real" and that they "may contain CGI effects."
Full Fact has contacted ViralVideoLab and will update this piece if they respond. The video of the tomato from that account is on YouTube with the title "Watch GMO Tomato Swim in Saltwater - The Fish Gene Effect Exposed!"
In this higher-quality version, it is easier to see that the video has been edited to make it look like the piece of tomato is moving in an unnatural way. For example, there are no ripples in the water when the piece of tomato moves, and a piece of negative space in the tomato flesh, revealing the bowl beneath, stays exactly the same shade as it 'swims' around, suggesting it comes from a still image.
Read more at fullfact.org