Giant rats might sound like the stuff of nightmares, but these behemoth rodents are working overtime to change the reputations of rats everywhere.
African giant pouched rats, native to sub-Saharan Africa, are among the largest rats in the world, measuring in at about 3 feet from head to tail. They also possess some of the world's finest sniffers, and government officials want to breed armies of these mammoth muroids to descend upon fields around the world to detect land mines, reports Phys.org.
Land mines kill or injure thousands of people every year, and finding and disarming them before they can explode is a hazardous and laborious job ... for humans. Giant rats, on the other hand, can scour land more efficiently using nothing more than their natural senses to detect the mines. Furthermore, even though these rats are gigantic by rodent standards, they're still light enough to avoid triggering a land mine to explode.
It also helps that pouched rats are particularly amenable to training as you can see in the video below.
We have a lot to learn about giant rats
There's one concern, however. Scientists know very little about their biology or social structure, making them difficult to breed in captivity. But new research out of Cornell University is beginning to shed some light on these rats' mysterious sex lives, and it has a lot to do with those powerful snouts of theirs.
"We wanted to understand their reproductive behaviors and olfactory capabilities, because they have been so important in humanitarian work," said Alex Ophir, co-author on the new research.
Researchers learned that reproductive success in these rats depends on the ability of males to smell when females — who have an unusually delayed sexual development — come into maturity. Furthermore, the potency of the males' noses was found to highly depend on exposure to hormones while still in utero. Thus, the conditions under which the rats are kept while still in the womb have a major impact on their ability to breed successfully later in life.
This is different than how it works for most rodents, and it's essential knowledge for breeders.
"It is amazing to think that in utero experiences can lock in the ability of these males to detect differences in female reproductive availability," said Ophir. "Our results raise interesting evolutionary questions, like how does natural selection operate on characteristics that are largely determined by chance features of the uterine environment?"
Since the potency of their sniffers is also important for the rats' success in detecting land mines, this knowledge might also help to breed better rat land mine-finders.
Check out the video above to see these charismatic rats in action, learning how to sniff out land mines. It might just change your impression of rodents entirely.