Be­fore the Back­yard

Early his­tory of the hen, by Andy Cawthray

Country Smallholding - - Inside This Month -

Chick­ens weren’t al­ways chick­ens, at least not in the way we think of and see them to­day or even a cou­ple of cen­turies ago. The hum­ble chicken in the 21st Cen­tury is prob­a­bly the most pro­lific bird on the planet. Did you know that there are more chick­ens around the globe than there are peo­ple? In 2002, the Food and Agri­cul­ture Or­ga­ni­za­tion of the United Na­tions es­ti­mated that there were 19bn live chick­ens in the world, with China hav­ing the largest pop­u­la­tion, fol­lowed by the US, In­done­sia and Brazil. This means that with a world hu­man pop­u­la­tion of just over 7bn, there are al­most three times as many chick­ens as there are peo­ple on the Earth at any one time.

This was not al­ways the case, how­ever, be­cause the chicken be­gan its ex­is­tence as a rather lo­calised, ob­scure, ground dwelling pheasant in the jun­gles of South East Asia. In truth, they are classed with sim­i­lar birds in the tax­o­nomic or­der Gal­li­formes (com­monly called game­birds or gal­li­forms). This group in­cludes — in ad­di­tion to the chicken and its wild fore­run­ner the jun­gle fowl — tur­keys, pheas­ants, quail, par­tridges, guinea fowl and peafowl.

Gal­li­forms in gen­eral are adapted to life on the ground and, as a re­sult, tend to be heavy in the body when com­pared to other birds. While we don’t con­sider chick­ens to be fly­ers, Gal­li­formes are not viewed as flight­less, with some ca­pa­ble of flight,

The his­tory of the most abun­dant bird on the planet may be doc­u­mented from do­mes­ti­ca­tion on­wards, but the ac­tual ori­gin and pre­his­tory of the chicken re­mains as com­plex a ques­tion as to which came first — it or the egg

al­though none of them are par­tic­u­larly strong at tak­ing to the air. In the wild, most of the species in the or­der use their half flight abil­ity for the pri­mary pur­pose of avoid­ing preda­tors.

If, while out walk­ing, you have ever hap­pened upon a pheasant, you will be fa­mil­iar with the sud­den ex­plo­sion of wing flap­ping as the bird takes off. This is usu­ally ac­com­pa­nied by an alarmed squawk. This is a de­fence mech­a­nism de­signed to star­tle a po­ten­tial threat or a preda­tor and it usu­ally lasts for only a few mo­ments, al­though it is suf­fi­ciently long enough for the bird to land and put a fair few me­tres of dis­tance be­tween it­self and dan­ger. It seems likely that it was Charles Dar­win who first pro­posed that the chicken was evolved from gal­li­forms, pri­mar­ily the jun­gle fowl ( Gal­lus gal­lus) and, most prob­a­bly, the red jun­gle fowl. The red jun­gle fowl, which has the broad­est range of the jun­gle fowl, most re­sem­bles the do­mes­tic chicken in ap­pear­ance and be­hav­iour. In fact, many novice and even some ex­pe­ri­enced poul­try en­thu­si­asts can and do mis­take it for a chicken, al­though truly wild ex­am­ples of the breed are in­fre­quently en­coun­tered. This species is among a group of four sur­viv­ing and as many as 13 ex­tinct pheasant-type species that are found from western In­dia through the south­ern reaches of Asia and into the is­land chains of In­done­sia and the Philip­pines. The birds gen­er­ally dwell on the jun­gle floor and on the mar­gins of grass­lands that edge forested ar­eas. The ranges of these closely-re­lated species rarely in­ter­sect, how­ever, so there is lit­tle pos­si­bil­ity of nat­u­ral hy­bridi­s­a­tion be­tween them. This in­di­cates that man must have in­flu­enced the evo­lu­tion of the chicken at the very be­gin­ning as op­posed to na­ture tak­ing its course un­aided.

The red jun­gle fowl’s cousin

The other jun­gle fowl species have rel­a­tively small ranges and are mostly iso­lated. The grey jun­gle fowl ( Gal­lus son­ner­atii), some­times called Son­nerat’s jun­gle fowl, is found in the west­ern­most part of the over­all range of jun­gle fowl, gen­er­ally in penin­su­lar In­dia. It dif­fers most strik­ingly from its red jun­gle fowl cousin in its comb — the small points and min­i­mal ser­ra­tions of the grey jun­gle fowl comb are clearly in con­trast with the more chicken-like ‘sin­gle’ comb of the red jun­gle fowl.

The re­main­ing two jun­gle fowl species can be found iso­lated on some of the is­lands that lie within the over­all range of the Gal­lus genus. The Sri Lankan jun­gle fowl ( Gal­lus lafayetii; pre­vi­ously called the Cey­lon jun­gle fowl) is found only on the is­land of Sri Lanka off the east­ern tip of south­ern In­dia, while the green or Ja­van jun­gle fowl ( Gal­lus var­ius) is found on a few is­lands in western In­done­sia, in­clud­ing Java and Bali.

It is un­der­stand­able how evo­lu­tion­ary the­ory would iden­tify the red jun­gle fowl as be­ing the pre­cur­sor to the chicken we know and love to­day. How­ever, it is not be­yond be­lief that the chicken may have evolved down all lines of the jun­gle fowl. Even to­day the true roots of the Arau­cana are sub­ject to de­bate, with stud­ies con­tin­u­ing into its true ori­gins. The ones seen to­day most cer­tainly will be re­lated in some way to the orig­i­nal jun­gle fowls, al­though there is ev­i­dence to sug­gest that the blue egg-lay­ing bird that was dis­cov­ered in north­ern Chile (later to be known as the Arau­cana) may, in fact, have no Asian roots at all and may not be re­lated to any of the four foun­da­tion species of jun­gle fowl.

The his­tory of the most abun­dant bird on the planet may be doc­u­mented from do­mes­ti­ca­tion on­wards, but the ac­tual ori­gin and pre­his­tory of the chicken re­mains as com­plex a ques­tion as to which came first — it or the egg.

NEXT MONTH: The his­tory of the chicken af­ter early do­mes­ti­ca­tion.

TOP: The Sri Lankan jun­gle fowl is found on the is­land of Sri Lanka in jun­gle like this ABOVE: It seems likely that Charles Dar­win first pro­posed that the chicken was evolved from Gal­li­formes

The chicken be­gan its ex­is­tence as a ground dwelling jun­gle pheasant

Man must have in­flu­enced the evo­lu­tion of the chicken from the very be­gin­ning

Chick­ens are classed in the same tax­o­nomic or­der (Gal­li­formes) as pheas­ants

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