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Wader

2007 Schools Wikipedia Selection. Related subjects: Birds

                    iWaders
   Semipalmated Sandpiper (Calidris pusilla)
   Semipalmated Sandpiper (Calidris pusilla)
           Scientific classification

   Kingdom:  Animalia
   Phylum:   Chordata
   Class:    Aves
   Order:    Charadriiformes
   Suborder: Charadrii

                                  Families

     * Scolopacidae
     * Rostratulidae
     * Jacanidae
     * Thinocoridae
     * Pedionomidae
     * Burhinidae
     * Chionididae
     * Pluvianellidae
     * Ibidorhynchidae
     * Recurvirostridae
     * Haematopodidae
     * Charadriidae

   Dunlin (Calidris alpina).
   Enlarge
   Dunlin (Calidris alpina).

   Waders, called Shorebirds in North America (where "wader" is used to
   refer to long-legged wading birds such as storks and herons), are
   members of the order Charadriiformes, excluding the more marine
   web-footed seabird groups. The latter are the skuas (Stercoraracidae),
   gulls (Laridae), terns (Sternidae), skimmers (Rhynchopidae), and auks
   (Alcidae). Also, the pratincoles (Glareolidae) and the Crab Plover
   (Dromadidae), which look more similar to waders, are closely related to
   the seabirds.

   This leaves about 210 species, most of which are associated with
   wetland or coastal environments. Many species of Arctic and temperate
   regions are strongly migratory, but tropical birds are often resident,
   or move only in response to rainfall patterns. Some of the Arctic
   species, such Little Stint are amongst the longest distance migrants,
   spending the non-breeding season in the southern hemisphere.

   The majority of species eat small invertebrates picked out of mud or
   exposed soil. Different lengths of bills enable different species to
   feed in the same habitat, particularly on the coast, without direct
   competition for food. Many waders have sensitive nerve endings at the
   end of their bills which enable them to detect prey items hidden in mud
   or soft soil. Some larger species, particularly those adapted to drier
   habitats will take larger prey including insects and small reptiles.

   Many of the smaller species found in coastal habitats, particularly but
   not exclusively the calidrids, are often named as "Sandpipers", but
   this term does not have a strict meaning, since the Upland Sandpiper is
   a grassland species.

   In the Sibley-Ahlquist taxonomy, waders and many other groups are
   subsumed into a greatly enlarged Ciconiiformes order. However, the
   classification of the Charadriiformes is one of the weakest points of
   the Sibley-Ahlquist taxonomy, as DNA-DNA hybridization has turned out
   to be incapable of properly resolving the interrelationships of the
   group. Formerly, the waders formed the suborder Charadrii, but this has
   turned out to be a " wastebin taxon", uniting no less than four
   charadriiform lineages in a paraphyletic assemblage. Following recent
   studies (Ericson et al., 2003; Paton et al., 2003; Thomas et al.,
   2004a, b; van Tuinen et al., 2004; Paton & Baker, 2006), the waders may
   be more accurately subdivided as follows:
     * Suborder Scolopaci
          + Family Scolopacidae: snipe, sandpipers, phalaropes, and allies

     * Suborder Thinocori
          + Family Rostratulidae: painted snipe
          + Family Jacanidae: jacanas
          + Family Thinocoridae: seedsnipe
          + Family Pedionomidae: Plains Wanderer

     * Suborder Chionidi
          + Family Burhinidae: thick-knees
          + Family Chionididae: sheathbills
          + Family Pluvianellidae: Magellanic Plover

     * Suborder Charadrii
          + Family Ibidorhynchidae: Ibisbill
          + Family Recurvirostridae: avocets
          + Family Haematopodidae: oystercatchers
          + Family Charadriidae: plovers and lapwings

   In keeping more in line with the traditional grouping, the Thinocori
   could be included in the Scolopaci, and the Chionidi in the Charadrii.
   However, the increasing knowledge about the early evolutionary history
   of modern birds suggests that the assumption of Paton et al. (2003) and
   Thomas et al. (2004b) of 4 distinct "wader" lineages (= suborders)
   already being present around the C-T boundary is correct.

   Retrieved from " http://en.wikipedia.org/wiki/Wader"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
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