ON THE WING

“Why did the chicken cross the road?” goes the Tasmanian joke when drivers spot cockerels (pictured) strutting at the side of the highway. The joke even featured in a Sunday Tasmanian headline once, when the newspaper carried a story about a notorious hotspot for unwanted cockerels, at the Kingston end of the Southern Outlet.

The issue of the rogue cockerels is generally linked to a growing trend to selfsufficiency, when people rearing chicks for egg production in backyards are faced with the problem that half the offspring is male.

The fact that these birds are merely dumped by the roadside might provide a sad commentary on how many people regard the chicken, but it is also putting the species in the spotlight as the most important bird on the planet in what it means to humankind.

Scientists are certainly seeing it that way. What started out as the red junglefowl (Gallus gallus) in south-east Asia has become a symbol of a new geological age, the Anthropocene, to follow the current epoch, Holocene.

The chicken has become the world’s most common bird. Its population is so vast it cannot possibly be counted but, as a guide, the Australian Chicken Meat Federation says about one million chickens are slaughtered every day in Australia. In the US, a figure of 22 million is given.

Worldwide, 60 billion might be killed each year.

The rise of the chicken worldwide sees it playing an epoch-defining role for humanity, as its bones could become the key fossil evidence for the dawn of the age in which humankind came to dominate the planet.

As Professor Jan Zalasiewicz, a geologist at the University of Leicester in Britain and the chair of the Working Group on the Anthropocene, puts it: the domestic chicken has been fossilised in thousands of landfill sites. The bird looks set to be granted immortality.

The chicken was first domesticated between 7000 and 10,000 years ago. The wild junglefowl was a poor flier, making it the perfect catch.

However, even in the early 20th century chickens were primarily sources of eggs. Male birds were eaten.

The transition to the ubiquitous meat of today began with the discovery of vitamin D in the 1920s, meaning the birds could be housed indoors all year round, rather than let out in the summer to soak up sunlight.

Global consumption of chicken expanded enormously as factory farming took off after World War II.

The chicken’s popularity has created its own folklore, which includes the question: why did the chicken cross the road?

The history of the chicken joke might be obscure, but we all know the answer: because it wanted to get to the other side.