People cannot keep eating meat at the same rate they have been, according to broadcaster David Attenborough.
The natural historian made the comments during an interview for the upcoming issue of Radio Times magazine.
According to Sir David, he has lost his appetite for meat, and he says he thinks he's been inspired by the state of the planet.
"We can't go on eating meat at the rate we have been," he said when asked whether people needed to reduce their meat consumption.
"I haven't been a doctrinaire vegetarian or vegan, but I no longer have the same appetite for meat. Why? I'm not sure.
"I think subconsciously maybe it's because of the state of the planet. Although, I've never really been one for eating enormous meals and I'm not particularly a gourmet either, so I can't pretend that I'm feeling deprived in any way or that it's cost me all that much."
Eating animals - and the planet
Sir David's thoughts about the impact of animal agriculture on the planet are consistent with a major study published in 2018, which offered the most comprehensive analysis ever undertaken of the planetary damage created by farming.
"A vegan diet is probably the single biggest way to reduce your impact on planet Earth, not just greenhouse gases, but global acidification, eutrophication, land use and water use," lead researcher Joseph Poore, at the University of Oxford, UK, told The Guardian.
"It is far bigger than cutting down on your flights or buying an electric car."