Though, for the most part NATURE isn't so much responsible for these as FARMERS are...
---With bonus Pig Facts!---
Pigs are omnivores, which means that they consume both plants and animals. Pigs will scavenge and have been known to eat any kind of food, including dead insects, worms, tree bark, rotting carcasses, garbage, and even other pigs.
Ton Pig (above) was a domestic hog from China owned by Xu Changjin that weighed in at 900 kg. Ton died from lack of mobility due to obesity on February 4, 2004. It was sent to the Liaoning Agriculture Museum in Shenyang, for display.
The Domestic Pig (Sus scrofa domesticus) is usually given the scientific name Sus scrofa, although some authors call it S. domesticus, reserving S. scrofa for the Wild boar. It was domesticated approximately 5,000 to 7,000 years ago.
Compared to other artiodactyles, their head is relatively long, pointed, and free of warts. Their head and body length ranges from 900-1,800 mm (35-71in) and can weigh 50-350 kg (110 - 772lb).
In the wild, they are foraging animals, primarily eating leaves and grasses, roots, fruits and flowers. Occasionally, in captivity, pigs may eat their own young, often if they become severely stressed.
Pigs are believed to have been domesticated from wild boar as early as 9000 BC in the Near East and separately in China at about the same time.
Big Norm (not pictured) was owned by Robert Peterson. Although Norm got regular hog feed, he started to grow to freakish proportions. A cooperative extension agent was able to calculate Norm's weight at 1600 lb (730 kg) and he was 8 ft (2.4 m) long, and 4 ft (1.2 m) high.
Intensive piggeries (or hog lots) are a type of factory farm specialized for the raising of domestic pigs up to slaughter weight.
[how amazing is the word "piggery"!?]
photos: internet far and wide
infoz:
wiki-piggy-iasee also:
list of big ol' pigs Oh and let's not forget these alleged giants and the assholes who allegedly killed them:
Monster Hog Hogzilla Also notable and apparently verified:
Coursey Hog