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Home , Alcedo, Ceyx (bird), Emu, Ispidina, Kiwi (bird), Malachite kingfisher

3.1- Old Jaws Atlas of uncorrected proofs Copyrighted Material

Ratites &

y the end of the Period, some 65 million ago, birds were already P Size of orders The basics of evolving within two distinct lineages, known by some as “super-orders”: the Number of in B The taxonomy of birds – the way in which they are classified within the kingdom and the . The former, which is the more primitive, today Percentage of total bird species Out of order? – has evolved over time. Recent decades have seen a shift away from a traditional system comprises only two orders. The latter comprises all the rest and thus accounts for some based largely on anatomical similarities towards one based on evolutionary affinities Bird taxonomy remains highly contentious. Many scientists 99.4 percent of modern species. traced via genetics. Nonetheless, the basic hierarchy of taxonomic rankings pioneered disagree about the orders into which birds are divided, and The Palaeognathae derive their name from the ancient Greek for “old jaws”. This the relationships between them, as fresh studies of by Swedish scientist Carolus Linnaeus (1707–78) has changed little and still provides a refers to the complex structure of their bony palate, which is more reptilian than in , DNA and the record continue to challenge useful navigation tool around the world of birds. other birds, and indeed paleognaths are the most primitive of living birds. The group accepted wisdom. The integrity of species is also under At the broadest level, modern birds are the only extant members of the Aves, question, with many birds that were once thought of as falls into two orders. The Struthioniformes, or , are a disparate collection of large, dierent races of a single species having since been Tinamiformes to which they all belong. Aves is one of seven classes within the subphylum Vertebrata flightless birds – further divided by some authorities into four distinct assigned full species status; a process known by 47 species ( with internal skeletons), the others being , reptiles, amphibians, and birdwatchers as “splitting”. orders. The Tinamiformes comprise the very different and somewhat 0.47% Struthioniformes three groups of . These are all part of the phylum Chordata, within the kingdom For consistency and ease of reference, this chapter -like tinamous, which are confined to South and Central 10 species Animalia. loosely follows the taxonomic model adopted by the America. In all paleognaths it is the male that incubates the 0.1% Classification within Aves varies by authority. Anything from 23 to 29 orders of British Trust for , which in turn is based largely , only receiving some female assistance in the case of bird are recognized. Collectively, these comprise (again, depending on authority) on Perrins (2003), following Sibley and Monroe (1990). the . 172 families, 2,057 genera and 9,845 species. The chart below gives an example of the taxonomic status of just one bird species.

Q Struthioniformes: ostrich, kiwis, allies P Taxonomic status of Malachite Struthioniformes are also known as ratites, from the Latin for “raft”. This refers to the birds’ lack of a keeled for anchoring the wing muscles, and so points to their defining Class characteristic: flightlessness. Associated features include reduced wings and that lack Aves (birds) stiffened vanes. Modern ratites are divided into five families, considered by some authorities ( to be full orders. The largest – indeed the Order The class Aves falls into a number of orders: novaehollandiae) largest living bird – is the Ostrich () of , which may top 2 metres (6 ft 7 in) 28 are recognized in this chapter. in height. Next, are the and () of Australasia, followed by the rheas of (). With the Each order falls into a number of families. Among 10 exception of the jungle-dwelling cassowaries, Alcedinidae other families in the order Coraciiformes are the these birds inhabit open country, where strong legs enable them to get around at speed. Much Meropidae (bee-eaters) and Coraciidae (rollers). smaller are the five species of (Apterygidae) distribution of order Struthioniformes from . These -sized, Each family falls into a number of genera. There are distribution of family Dromaiidae (emus) nocturnal birds use an acute to sniff out food beneath the soil. two other genera in Alcedinidae: (dwarf river kingfishers kingfishers) and (pygmy kingfishers) Q Tinamiformes: tinamous The tinamous look superficially like . Species In fact, these plump, ground-dwelling birds are The Malachite Kingfisher is one of 17 similar species in closely related to the ratites and are among the Alcedo cristata the genus Alcedo. Others include the Common most ancient of birds, with a fossil record that Malachite Kingfisher Kingfisher (Alcedo atthis). goes back at least 10 million years. The single family (Tinamidae) is confined to South America

R and comprises at least 47 species across nine e d - w genera, ranging in size from 20 to 53 cm (8 in to The naming of species in g e d 1 ft 8 in). Unlike ratites, tinamous have a keeled T in The unique two-word scientific name assigned to each bird is known as a binomial. am breastbone and can short distances on their ou (Rh ns) ynchotus rufesce short, rounded wings. Nonetheless, they spend The first word denotes its genus, the second its species. In the above example most of their time on the ground, where strong cristata, which means “crowned”, refers to the distinctive of the Malachite legs help them get around and find food – Kingfisher. Scientific names constitute a universal language, avoiding the confusion including seeds, fruits and – and cryptic helps conceal them from of common names, which may vary between countries. predators. Tinamous occur in all , from Some species have two or more different geographical forms, which are not to and alpine tundra. distinct enough to be treated as separate species. These are known as , or Though seldom seen, they often betray their races, and are assigned a three-part name, or trinomial. For example, the Common presence with loud, whistled calls. Buzzard, Buteo buteo, has up to eight recognized subspecies across the Old World, distribution of order Tinamiformes including the East Asian race Buteo buteo vulpinus and the race

Buteo buteo insularum. Copyright © Myriad Editions

44 14–15 Bird Beginnings 45