'Fallout 76's Mutated Animals Might Be Explained by Genetic Radiation

Are Mega Sloths and two-headed bears really possible?

As you wander through the irradiated wasteland of Fallout 76 looking for good loot and shooting at fellow survivors, you might wonder about the drastic mutations to the local flora and fauna caused by the nuclear fallout that followed the Great War — especially those cute but deadly Mega Sloths like the one in the Fallout 76 trailer above.

But wait, would nuclear radiation really create these kinds of giant, mutated animals?

We need look no further than the wildlife around Chernobyl to learn about the effects nuclear radiation has on animals. Genetic mutations like certain deformities can and do happen in extreme cases like in Chernobyl, where a catastrophic malfunction of a nuclear reactor in April 1986 irradiated the surrounding area.

Today, hundreds of stray dogs in the area thrive without human intervention. But other than residual heightened levels of radiation and the consequential shorter life expectancy brought on by random deformities and higher rates of cancer, they seem to be doing mostly fine.

Unfortunately for Fallout fans, radiation could never actually cause a creature to drastically increase in size to that extent, even after decades of exposure.

This fox living within the exclusion zone of Chernobyl no doubt has been exposed to radiation, but looks mostly no worse off for it.

Vic Harkness, Flickr

Dr. Timothy Mousseau, who studies how radiations affects the wildlife around Chernobyl and Fukushima, told Motherboard in 2015 that if radiation doesn’t kill wildlife, the worst it can do is cause harmful mutations.

“The big effect is going to be having populations that are unhealthy and less fit, less able to deal with changes in the environment, less able to repopulate,” he explained.

Radiation from any source usually causes cancer in nearby populations, but the effects aren’t seen for years unless the radiation levels are extreme.

Mutations like this one in 'Fallout 76' are somehow beneficial.


In a 2015 interview with Kotaku, genetic scientist Louise Gregory from the Genetics and Genomic Medicine Programme in London similarly dismissed the type of mutations seen in the Fallout games.

“I think the creatures in the Fallout world that you describe are bonkers,” Gregory said. “But very imaginative and not at all implausible.”

Gregory explained that Fallout’s humanoid Ghouls especially don’t make much sense, as high exposure to radiation would cause people to “literally burn/decay from the inside,” rather than transform people into skeletal creatures that occasionally behaved like zombies.

Then again, mutations like the two-headed bear could feasibly happen.

“Certain genes that are mutated in patients that I find and come across actually have whole sections deleted, doubled or changed — and they grow two of something!” Gregory said. “OK, maybe not heads, but they could have two pituitary glands, for example, or only one eye in the middle of their face. That’s very rare, but has been seen. So the two heads scenario could actually be plausible as an extreme genetic event.”

So there you have it. Giant irradiated sloths? Totally ridiculous. Two-headed bears? Scientifically possible.

This December, Inverse is counting down the 20 best science moments in science fiction this year. This has been #10.

Read our previous stories:

Related Tags