tundra
Explanation
The Joke
The comic shows a scientist standing at the edge of a melting landscape, arms spread in exasperation, saying: "Ah, dammit! This took decades of science and engineering and now the tundra is melting! Sorry, guys." The caption below reads: "Moments after woolly mammoths are reintroduced."
The joke imagines a scenario in which scientists have successfully accomplished the monumental feat of de-extinction -- bringing back woolly mammoths through decades of genetic engineering and painstaking work. But the moment they release the mammoths into their natural habitat (the tundra/permafrost), they realize that climate change has melted the very environment the mammoths need to survive. The scientist's casual "Sorry, guys" -- addressed to the mammoths -- is a darkly funny understatement for having spent decades on a project rendered pointless by a parallel catastrophe that everyone saw coming.
The Humor
The humor is rooted in a real tension in contemporary science. There are actual ongoing efforts to de-extinct the woolly mammoth (notably by companies like Colossal Biosciences), and there are simultaneous, well-documented concerns about permafrost and tundra loss due to climate change. The comic points out the absurd irony of pouring resources into bringing back an ice-age animal while simultaneously allowing the ice age environment to disappear. The scientist's tone -- annoyed but resigned, like someone who burned dinner -- perfectly undercuts the gravity of both the achievement and the failure.