When pigs swim

Elephants sneeze through their trunks. Obviously since the trunk is still their nose even though it is used not just for smelling but for touching, carrying, breathing as well. They are very loud and the spray is enormous. The sneeze comes from the throat and is an expulsion of air designed to clear the irritation in the nasal passage.

Land animals are not the only <g data-gr-id="86">sneezers</g>.  Marine iguanas eject salt through their nasal glands with a sneeze. And whales and dolphins have to breathe out and blow the water out before they can breathe in through their blowhole, fulfilling the same function as a sneeze. <g data-gr-id="101">Even fish cough</g> or sneeze to clear particulate matter in the water that clogs the gills.

 

This is mythology. Most four-legged land herbivores — cows, buffaloes, donkeys, moose, rhinos, <g data-gr-id="104">bison</g> and horses — can doze lightly on their feet, but they have to lie down to sleep deeply. When horses appear to be sleeping standing up, they can either be in a state of drowsiness or what is known as <g data-gr-id="97">slow wave</g> sleep, which is not quite as deep as REM (<g data-gr-id="98">rapid-eye movement</g>) sleep.

Even then, how does this work? The legs of horses [and other animals] have what’s known as the ‘stay apparatus. Their limbs contain tendons and ligaments that allow the animal to remain standing with minimal muscular effort, and thus allow them to stand — and even doze — for long periods.

Herd animals have another reason for standing a lot: To keep an eye out for danger. In a herd, not every animal is asleep — or lying down for that matter — at the same time. This allows the awake and/or standing herd members to act as sentinels against predators or other danger.

Pigs love water and are excellent swimmers who cross <g data-gr-id="96">water</g> to seek food, escape danger or find better living conditions. Some even hang out at beaches.

They aren’t the only surprising swimmers. Fishing spiders go underwater for 30 minutes at a time to avoid predators or find small fish to eat. They breathe underwater by trapping air in the water-repellent hairs on their abdomen. Diving bell spiders trap air in webs that cover their bodies like their namesake apparatus. Oxygen in the surrounding water diffuses into the bell, allowing them to stay submerged for long periods.

While most cats hate water, the endangered fishing cat of Asia is a fine swimmer that fishes by tapping the water to imitate insects then when fish come close, it dives in to get its quarry. The Turkish Van cat is known for its unusual love of water.

Paper wasps, cockroaches, praying mantises and fruit flies are among insects that <g data-gr-id="106">doze</g>. Fruit fly sleep is similar to mammal sleep and they even respond to sleep-inducing chemicals and caffeine, just like people. Differentiating between sleep and <g data-gr-id="107">sleep like</g> states in insects is difficult. Signs of true sleep are not moving, “<g data-gr-id="108">drooping</g> in the direction of gravity”, and more relaxed muscles.

Another indicator is how long it takes to jar the bug to alertness. Fruit flies show that they experience sleep deprivation like humans — a fruit fly deprived of sleep will subsequently need it more.

According to biologists butterflies rest but “but we don’t know if they sleep”. While butterflies rest in the evening, they also “can’t move when it goes below a certain temperature, a state that looks like sleep but is a different type of dormancy called torpor. Butterflies “put themselves to bed” in the late afternoon, hanging from such hiding places as leaves, bark, or even beer cans. Without adequate rest, they won’t forage as well and females will lay eggs on the wrong plants for their caterpillar offspring to eat. Bees also suffer from sleep deprivation. Bees inform each other about food sources and potential nest sites through a movement called a “waggle dance”. The study showed sleep-deprived bees behaved quite differently than bees with the more precise directional information. For instance, the sleepy bees’ dances were not as detailed – and thus not as helpful – as those of the bees that slept soundly.

Coprophagia is the term for an animal eating excrement — both their own and that of others. Dung beetles, rabbits, chimps, and domestic dogs are among animals that are members of this club. Most of them eat feces because it contains some undigested food — and thus vital nutrients — that would otherwise go to waste.

The small guts of rabbits don’t break down everything the first time, so they send it back a second time. They have two kinds of feces, the kind they eat and the kind they don’t. The kind they eat are called cecotropes — sometimes called “night feces” — nutrient-packed pellets that the rabbits eat fresh.

Chimpanzees don’t regularly eat their feces, but like rabbits, the most likely reason is some of the seeds they eat are only partly digested, and they eat them again to harvest those nutrients. Beetles also take advantage of raw materials in animal excrement, usually deposited by plant-eating mammals. Baby beetles, for instance, munch on solids, while adults have <g data-gr-id="115">specialised</g> mouthparts to slurp up the dung’s liquid parts.

Dogs may be attracted to undigested extras in scat, but the behaviour may also simply be a habit learned from their mothers. Nursing females will lick their puppies under the tail, which stimulates small secretions of urine and feces. These are immediately cleaned up by the mother by eating the feces. Puppies might mimic their mother’s <g data-gr-id="111">behaviour</g> for up to a year, and sometimes the habit persists into adulthood.