Happy New Year! 5th February marks start of a new year on the traditional Chinese calendar. It is celebrated as a national holiday in several East Asian countries besides China, including South Korea, Vietnam, soliand Malaysia. The calendar goes through 12-year cycles, with each year being assigned a particular animal. The order of these animals is based on the mythological ‘Great Race’, in which the Jade Emperor, deciding he wanted 12 animals to act as his personal guardians, organised a race to choose the top dozen creatures. The resulting rankings led to the Chinese zodiac, so we thought we’d take a closer look at these 12 animals, read on to learn more about these familiar but fabulous critters!
Rat
The most commonly-known species are black rat (Rattus rattus) or brown rat (Rattus novegicus); these are known as true (Old World) rats, originating from Asia. They can be kept as pets and have been done so since the late 19th century.
Rats are distinguished from mice by their size, being generally larger. The term rat is used loosely and is not actually a scientific term, since there are rodents in the sub-family Murinae which are not part of the Rattus genus.
Male rats are known as bucks, whereas females are known as does before mating or dams if they are pregnant or are a parent.
It is proposed that the tail of a rat functions as being used for thermoregulation or for proprioception (“sixth sense”).
Brown rats are often used as model organisms for scientific research, looking into diseases and the effects of drugs, but they are not as popular as mice.
Ox
Oxen are often trained as working animals and have been used as such since around 4000 BC. Usually found in pairs, they are generally used for ploughing fields or for transportation of agricultural load.
The average time oxen sleep is roughly only 4 hours a day.
Oxen are castrated bulls. Castration is the removal of the testes, epididymis and part of the spermatic chord from male animals, making them less aggressive and more docile in nature.
Tiger
The tiger (Panthera tigris), is the world’s largest cat species. They are mostly solitary animals, apart from when trying to secure a mate. They are strong swimmers and mark their territory by spraying urine on trees.
Approximately 3,890 tigers are left in the world from 10,000 at the start of the 20th century. This is largely due to poaching, habitat destruction, and habitat fragmentation. On top of this, sadly, the mortality rate of tiger cubs is 50% within the first two years after birth.
The tiger is closely related to the snow leopard (Panthera uncia), with the two species having diverged a relatively recent 2.88 million years ago.
Tigers are indigenous to Asia and the Pantheria tigris species is split into six subspecies; Bengal, Siberian, Indochinese, Malayan, South China, and Sumatran. However, they once had a much wider range, with fossils indicating the presence of tigers in Alaska during the last glacial ice age (100,000 years ago).
Rabbit
The European rabbit (Oryctolagus cuniculus) is the only species of rabbit to have been domesticated by humans, whilst all 305 other rabbit breeds, are descended from this species.
In 2011 a fossil rabbit species was uncovered in Minorca, Spain dating from 3-5 million years old, which has been dubbed Nuralagus rex, and is believed to have weighed 12 kilograms – making it six times larger than modern rabbits.
Rabbits are one of a handful of animals that are physically incapable of vomiting, because they cannot perform reverse peristalsis (i.e., their stomach muscles aren’t strong enough to push ingested food back up the oesophagus). Vomiting is an important survival tactic to remove potentially harmful food, but it’s believed that rabbits overcome their lack of vomiting skills by careful avoidance behaviours to ensure they don’t eat things that they might regret, but there is relatively little research in this field.
Dragon
The dragon is not an easy member of the zodiac to write about because, sadly, they’re not real. The word ‘dragon’ actually comes from the Latin for ‘huge serpent’, and the creatures are found in the ancient myths of almost every country in the world.
This prevalence of the dragon myth globally is what leads many to think that the discovery of huge dinosaur bones, which wouldn’t have been easily explained before the advent of palaeontology, led people to believe that they must be the remains of these gigantic beasts.
There are however, a few examples of some ‘real’ dragons; most notably the Komodo dragon (Varanus komodoensis, pictured below), which can grow to an impressive 3 meters long and possesses deadly venom which it uses to kill is prey (read more on that here).
Snake
Snakes are often characterised as sneaky and cunning, and the zodiac snake is a prime example of these stereotypes, slithering out of the grass to take the horse by surprise and sweep into sixth place in the race.
There are currently believed to be around 3,600 species of snake, having evolved from burrowing aquatic lizards in the Jurassic period.
Approximately 725 of these species are venomous, with the inland taipan (Oxyuranus microlepidotus) claiming the title of most toxic, with one bite lethal enough to kill approximately 100 people.
Fascinatingly, there have been reports that even after decapitation, some snakes’ severed heads can still bite.
Horse
Horses (Equus ferus caballus) as we know them have evolved over millions of years from the extinct genus, Eohippus, to become the domesticated mammals we recognise today. Notably, fossils suggest that the modern horse evolved to have its single-toed hoof – likely to increase bone strength and aid running – since its ancestors had up to four toes. Vestigial toes can still be found on horses’ skeletal structures today.
…And it is these single toes that horses rely upon to catch that mid-afternoon nap. Yes! Horses can sleep standing up – sort of. For their REM sleep, horses need to lie down as much as the best of us. But for animals in the wild, long stretches of deep sleep can be dangerous and make them vulnerable to prey so horses get their rest by also lightly dozing throughout the day whilst standing up.
This, along with the fact that horses get about two to three hours of REM sleep a night, means that students have a lot more in common with horses than neigh-sayers would have you believe.
Goat
Goats (Capra aegagrus hircus) were one of the earliest animals to be domesticated by humans, as far back as over 9000 years ago.
Both male and female goats have beards.
And teeth. Goats are born with teeth. Baby goats. With teeth. These eventually fall out to and give way to 32 adult teeth.
In herds, a female goat dominates the herd throughout the year until mating season, at which point a male goat dominates.
Monkey
Grinning is a sign of aggression in monkeys.
Some species are close to extinction, such as the Hainan Black-Crested Gibbon, which is a critically endangered species, with only twenty remaining.
Notorious for being the most mischievous animal, monkeys are also amongst the most intelligent. They have been used by humans throughout the years for many highly demanding tasks, including being launched into space by a number of countries (e.g. the United States and France) before humans were sent.
Although monkeys and chimpanzees are not one and the same, this tale of science and ethics is worth noting. In the 1970s, the New York Blood Center opened a research laboratory, Vilab II, in Liberia and injected over a hundred chimpanzees with infectious diseases, testing them for hepatitis. The research eventually helped lead to the development of the hepatitis B vaccine but in 2005, the center closed amid general protests about animal cruelty. The chimpanzees, over sixty in number, were retired on an island (dubbed ‘Monkey Island’) as they cannot swim and for ten years, were under the care of the center until 2015, when, during Liberia’s Ebola outbreak, the center withdrew funding and deemed the chimpanzees the government’s responsibility. The animals were left to starve until a coalition of people, headed by the Humane Society of the United States, stepped in to provide funding for care. In 2017, a multi-million dollar agreement was reached with the New York Blood Center, resulting in the two organisations sharing financial responsibility for the long-term care of the chimpanzees.
Rooster
A subspecies of the red and grey junglefowl, domesticated around 7000BC in China and India.
They are omnivores, they not only eat seeds and insects but also mice and lizards and other smaller animals!
Roosters reproduction is influenced by the sun; their testes shrink and grow seasonally! (something nice to think about when you next tuck into your chicken dippers)
Chickens are found on every continent in the world, apart from Antarctica!
Dog
Their intelligence and excellent hunting abilities made them very useful for early human populations.
Artificial selection by humans over the past 200 years has led to the emergence of countless dog breeds from the Chihuahua to the Irish Wolfhound.
A study using MRI found that dogs show activity in the same parts of their brain as humans do in response to human voices and sounds!
Pig
Pigs were domesticated around 9000 years ago and are descended from the wild boar (Sus scrofa) and the Sulawesi warty pig (Sus celebensis).
Pigs have very poor eyesight, but a very strong sense of smell.
Androstenone is a steroid and was the first mammalian pheromone to be identified. Male pigs contain high amounts of this steroid in their saliva and when inhaled by a female pig in heat it induces the female to assume a mating stance.
Truffles also contain this steroid which is why female pigs are used as truffle hunters!
