Other than humans, animals just eat what they find, as they find it 鈥� no cooking, no washing. Why aren鈥檛 they vomiting all the time?
Nikola Stojanovic
Leskovac, Serbia
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Animals, particularly wild ones, have digestive systems that are adapted to handle raw and uncooked foods, which are their natural diet. Their stomach acidity is usually higher, enabling them to break down raw meat, bones and other tough materials more efficiently, as well as killing harmful bacteria.
Mike Follows
Sutton Coldfield, West Midlands, UK
Carnivores can suffer from food poisoning, but there are several reasons why they are less susceptible than we are.
For one, fresh meat is much less likely to be contaminated with bacteria. Also, carnivores have a simpler, smoother and shorter digestive tract compared with omnivores and especially herbivores. This means that food spends less time passing through their guts and any bacteria will have less time to multiply to a level that would make them ill.
Besides, animals tend to avoid eating the digestive tract and other parts of their prey that are more likely to be contaminated with bacteria. Finally, carnivores have stronger stomach acids, which are more likely to kill any pathogens that might be present.
Indeed, some animals like vultures, which specialise in eating carrion, have particularly strong stomach acids. While other scavengers can spread pathogens far and wide via their faeces, vultures are the ultimate clean-up crew because pathogens will die before they are passed out in their guano. The stomach acid of some vultures can even dissolve bone. Indeed, the bearded vulture (Gypaetus barbatus), also known as the ossifrage or 鈥渂one-breaker鈥�, feeds almost exclusively on bone.
While individual animals can succumb to poison, a species can adapt to tolerate it or learn to avoid it. The cane toad (Rhinella marina), which is poisonous, was introduced to Australia in 1935 to control beetle pests that were damaging sugarcane crops. The Australian freshwater crocodile (Crocodylus johnstoni) has adapted to consume only the hind legs, which are free of poison.
In contrast, our supply of food is increasingly sanitised; as well as making the food more nutritious, cooking destroys many pathogens that remain. Our reduced exposure to pathogens weakens our immunity and makes us more susceptible to food poisoning when we do consume contaminated food. This is exacerbated by the fact that, as omnivores, our digestive tracts are longer than those of carnivores, which affords pathogens ample time to multiply to levels that can make us ill.
Garry Trethewey
Arkaroola Wilderness Sanctuary, South Australia
I once lived in an ashram in a Western country. Everyone was nominally vegan, but with varying degrees of compliance. Occasionally, a bout of diarrhoea and vomiting would sweep the place, and we noticed the intensity was in proportion to the degree of veganism 鈥� the most compliant had the worst of it. Eventually, someone noticed mouse poos in the rice jar. Once it was mouse-proofed, we had no further bouts.
I am now involved with conservation and habitat restoration, as well as dealing with introduced predators. We find it easy to bait foxes and wild dogs, but not cats. Canids have long noses, full of smell receptors, and can find smelly rotten meat from a distance and safely eat it. Cats, on the other hand, are visual stealth predators that sneak up and attack live animals 鈥� and don鈥檛 tolerate more than minimally rancid meat.
Shelton Harlow
Via Facebook
Ever had a dog? They vomit a lot鈥�
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