parent_taxon neomixis
The bee hummingbird , zunzuncito or Helena hummingbird (" ___MASK88___ helenae ") is a species of hummingbird . In geology , a supercontinent is the assembly of most or all of Earth ' s continental blocks or cratons to form a single large landmass . However , the definition of a supercontinent can be ambiguous . Many earth scientists , such as P . F . Hoffman ( 1999 ), use the term " supercontinent " to mean " a clustering of nearly all continents ". This definition leaves room for interpretation when labeling a continental body and is easier to apply to Precambrian times . Using the first definition provided here , Gondwana ( a . k . a . Gondwanaland ) is not considered a supercontinent , because the landmasses of Baltica , ___MASK60___ and Siberia also existed at the same time but physically separate from each other . The landmass of Pangaea is the collective name describing all of these continental masses when they were in proximity to one another . This would classify Pangaea as a supercontinent . According to the definition by Rogers and Santosh ( 2004 ), a supercontinent does not exist today . Supercontinents have assembled and dispersed multiple times in the geologic past ( see table ). The positions of continents have been accurately determined back to the early Jurassic . However , beyond , continental positions are much less certain . In paleogeography , Gondwana , also Gondwanaland , is the name given to an ancient supercontinent . It is believed to have sutured between about 573 and 510 million years ago ( ___MASK57___ ), joining East Gondwana to West Gondwana . Gondwana formed prior to Pangaea , and later became part of it . Dinosaurs are a diverse group of animals of the clade Dinosauria that first appeared during the Triassic . Although the exact origin and timing of the evolution of dinosaurs is the subject of active research , the current scientific consensus places their origin between 231 and 243 million years ago . They became the dominant terrestrial vertebrates after the Triassic  Jurassic extinction event 201 million years ago . Their dominance continued through the Jurassic and Cretaceous periods and ended when the Cretaceous  Paleogene extinction event led to the extinction of most ___MASK92___ groups 66 million years ago . India , officially the Republic of India (" Bhrat Gaarjya "), is a country in South Asia . It is the seventh - largest country by ___MASK73___ , the second - most populous country ( with over 1 . 2 billion people ), and the most populous democracy in the world . It is bounded by the Indian Ocean on the south , the Arabian Sea on the southwest , and the Bay of Bengal on the southeast . It shares land borders with Pakistan to the west ; China , Nepal , and Bhutan to the northeast ; and Myanmar ( Burma ) and Bangladesh to the east . In the Indian Ocean , India is in the vicinity of Sri Lanka and the Maldives . India ' s Andaman and Nicobar Islands share a maritime border with Thailand and Indonesia . Its capital is New Delhi ; other metropolises include Mumbai , Kolkata , Chennai , Bangalore , Hyderabad and Ahmedabad . A passerine is any ___MASK18___ of the order Passeriformes , which includes more than half of all ___MASK18___ species . A notable feature of passerines compared to other orders of Aves is the arrangement of their toes , three pointing forward and one back , which facilitates perching . Sometimes known as perching birds or , less accurately , as songbirds , the passerines form one of the most diverse terrestrial vertebrate orders , with over 5 , 000 identified species . It has roughly twice as many species as the largest of the ___MASK28___ orders , the ___MASK66___ . It contains more than 110 families , the second - most of any order of tetrapods ( after Squamata , the scaled reptiles ). The passerines contain several groups of brood parasites such as the viduas , cuckoo - finches , and the cowbirds . Most passerines are omnivorous , while the shrikes are carnivorous . The ___MASK96___ family of small passerine birds is a group of about 110 warblers found mainly in warmer southern regions of the Old World . They are often included within the Old World warbler family ___MASK11___ . The wedge - tailed jery (" ___MASK22___ flavoviridis ") is a small bird endemic to the east of Madagascar . The species has been the cause of some taxonomic confusion , it was originally placed with the jeries in the genus " Neomixis " ( Cisticolidae ) before being placed in its own monotypic genus ___MASK22___ , but still considered close to " Neomixis ". Recent research indicates it is part of an endemic Malagasy radiation currently known as the Malagasy warblers ( Cibois " et al ." 2001 ). Birds ( Aves ), also known as avian dinosaurs , are a group of endothermic vertebrates , characterised by feathers , toothless beaked jaws , the laying of hard - shelled eggs , a high metabolic rate , a four - chambered heart , and a lightweight but strong skeleton . Birds live worldwide and range in size from the bee hummingbird to the ___MASK23___ . They rank as the class of tetrapods with the most living species , at approximately ten thousand , with more than half of these being passerines , sometimes known as perching birds or , less accurately , as songbirds . The Malagasy warblers are a newly validated clade of songbirds . They were formally named ___MASK33___ in 2010 . The family currently consists of eleven species ( in eight genera ) of small forest birds . These birds are all endemic to Madagascar . The Old World babblers or timaliids are a large family of mostly Old World passerine birds . They are rather diverse in size and coloration , but are characterised by soft fluffy plumage . These are birds of tropical ___MASK2___ , with the greatest variety in Southeast Asia and the Indian subcontinent . The timaliids are one of two unrelated groups of birds known as babblers , the other being the Australasian babblers of the family Pomatostomidae ( also known as pseudo - babblers ). The ear is the organ of hearing and , in mammals , balance . In mammals , the ear is usually described as having three parts  the outer ear , middle ear and the inner ear . The outer ear consists of the ___MASK46___ and the ear canal . Since the outer ear is the only visible portion of the ear in most animals , the word " ear " often refers to the external part alone . The middle ear includes the tympanic cavity and the three ossicles . The inner ear sits in the bony labyrinth , and contains structures which are key to several senses : the semicircular canals , which enable balance and eye tracking when moving ; the utricle and saccule , which enable balance when stationary ; and the cochlea , which enables hearing . The ears of vertebrates are placed somewhat symmetrically on either side of the head , an arrangement that aids sound localisation . The superclass ___MASK64___ ( Ancient Greek s tetrapods , " four - footed "), or the tetrapods , comprises the first four - limbed vertebrates and their descendants , including the living and extinct amphibians , birds , mammals , reptiles and some ancient , exclusively aquatic creatures such as the Acanthostega . Tetrapods evolved from the lobe - finned fishes around 390 million years ago in the middle Devonian Period , with modern tetrapod groups having appeared by the late Devonian , 367 . 5 million years ago . The specific aquatic ancestors of the tetrapods , and the process by which land colonization occurred , remain unclear , and are areas of active research and debate among palaeontologists at present . A songbird is a ___MASK18___ belonging to the clade ___MASK35___ of the perching birds ( Passeriformes ). Another name that is sometimes seen as a scientific or vernacular name is Oscines , from Latin " oscen ", " a songbird ". This group contains some 4 , 000 species found all over the world , in which the vocal organ typically is developed in such a way as to produce a diverse and elaborate ___MASK18___ song . An endotherm ( from Greek  " endon " " within " and  " therm " " heat ") is an organism that maintains its body at a metabolically favorable temperature , largely by the use of heat set free by its internal bodily functions instead of relying almost purely on ambient heat . Such internally generated heat is mainly an incidental product of the ___MASK72___ ' s routine metabolism , but under conditions of excessive cold or low activity an endotherm might apply special mechanisms adapted specifically to heat production . Examples include special - function muscular exertion such as shivering , and uncoupled oxidative metabolism such as within brown adipose tissue . Only birds and mammals are extant universally endothermic groups of animals . Certain lamnid sharks , tuna and billfishes are also endothermic . Madagascar , officially the Republic of Madagascar , and previously known as the Malagasy Republic , is an island country in the Indian Ocean , off the coast of Southeast Africa . The nation comprises the island of Madagascar ( the fourth - largest island in the world ), and numerous smaller peripheral islands . Following the prehistoric breakup of the supercontinent Gondwana , Madagascar split from the Indian peninsula around 88 million years ago , allowing native plants and animals to evolve in relative isolation . Consequently , Madagascar is a biodiversity hotspot ; over 90 % of its wildlife is found nowhere else on Earth . The island ' s diverse ecosystems and unique wildlife are threatened by the encroachment of the rapidly growing ___MASK75___ population and other environmental threats . The ___MASK23___ or common ___MASK23___ (" ___MASK68___ camelus ") is either one or two species of large flightless birds native to Africa , the only living member ( s ) of the genus " ___MASK68___ ", which is in the ratite family . In 2014 , the Somali ___MASK23___ (" ___MASK68___ molybdophanes ") was recognized as a distinct species . Old World warblers are a large group of birds formerly grouped together in the ___MASK18___ family ___MASK11___ . The family held over 400 species in over 70 genera , and were the source of much taxonomic confusion . Two families were split out initially , the cisticolas into Cisticolidae and the kinglets into Regulidae . In the past ten years they have been the subject of much research and many species are now placed into other families , including the Acrocephalidae , Cettiidae , Phylloscopidae , and Megaluridae . In addition some species have been moved into existing families or have not yet had their placement fully resolved . A smaller family of warblers , together with some babblers formerly placed in the family Timaliidae and the parrotbills , are retained in a much smaller family ___MASK11___ . Hummingbirds are birds from the Americas that constitute the family ___MASK99___ . They are among the smallest of birds , most species measuring . Indeed , the smallest extant ___MASK18___ species is a hummingbird , the 5 - cm bee hummingbird weighing less than a U . S . penny ( 2 . 5 g ). ___MASK1___ is a genus of ___MASK18___ formerly placed in the Old World babbler family but now considered to belong to the Cisticolidae family . The genus comprises three small forest birds endemic to Madagascar : Stripe - throated jery ( ___MASK1___ striatigula ) Common jery ( ___MASK1___ tenella ) Green jery ( ___MASK1___ viridis ) Another species the wedge - tailed jery ( ___MASK22___ flavoviridis ) was until recently placed in this genus but recent biochemical studies suggest its true relationships lie elsewhere . Vertebrates comprise all species of animals within the subphylum ___MASK91___ ( chordates with backbones ). Vertebrates represent the overwhelming majority of the phylum Chordata , with currently about 64 , 000 species described . Vertebrates include the jawless fish and the jawed vertebrates , which include the cartilaginous fish ( sharks and rays ) and the bony fish .