Search results
Results From The WOW.Com Content Network
Vertebrates (/ ˈ v ɜːr t ə b r ɪ t s,-ˌ b r eɪ t s /) [3] are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebrata with some 65,000 species, by far the largest ...
A forelimb or front limb is one of the paired articulated appendages attached on the cranial end of a terrestrial tetrapod vertebrate's torso. With reference to quadrupeds, the term foreleg or front leg is often used instead. In bipedal animals with an upright posture (e.g. humans and some other primates), the term upper limb is often used.
A majority of paleontologists use the term "tetrapod" to refer to all vertebrates with four limbs and distinct digits (fingers and toes), as well as legless vertebrates with limbed ancestors. [ 15 ] [ 16 ] Limbs and digits are major apomorphies (newly evolved traits) which define tetrapods, though they are far from the only skeletal or ...
Agnatha (/ ˈ æ ɡ n ə θ ə, æ ɡ ˈ n eɪ θ ə /; [3] from Ancient Greek ἀ-(a-) 'without' and γνάθος (gnáthos) 'jaws') is a paraphyletic infraphylum [4] of non-gnathostome vertebrates, or jawless fish, in the phylum Chordata, subphylum Vertebrata, consisting of both living (cyclostomes) and extinct (conodonts, anaspids, and ostracoderms, among others).
A clade is by definition monophyletic, meaning that it contains one ancestor which can be an organism, a population, or a species and all its descendants. [ note 1 ] [ 10 ] [ 11 ] The ancestor can be known or unknown; any and all members of a clade can be extant or extinct.
The appearance of the early vertebrate jaw has been described as "a crucial innovation" [25] and "perhaps the most profound and radical evolutionary step in the vertebrate history". [ 26 ] [ 27 ] Fish without jaws had more difficulty surviving than fish with jaws, and most jawless fish became extinct during the Triassic period.
Named for the Comahue region, whose name means 'place of abundance', or perhaps 'where the water hurt', and Greek therium, meaning "beast". [citation needed] Conepatus chinga (Hog-nosed skunk) skunk: Nahuatl and Mapudungun: The genus name is most likely from conepatl, the Nahuatl name of the
[13] [14] Their diet is made up primarily of invertebrates such as insects and small vertebrates such as reptiles and birds. They may also eat eggs and vegetation. Many species are generalist predators, but some (such as the crab-eating fox) have more specialized diets. Most species of fox consume around 1 kg (2.2 lb) of food every day.