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194 Cards in this Set
- Front
- Back
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fossorial |
(of an animal) burrowing. (of limbs) adapted for use in burrowing.
+Fossorial locomotion of mammals is appendicular (forelimb). +Two basic approaches - scratch-diggers
+humeral rotation digging is best known in moles and shrew moles, may also be used by monotremes
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-oidea |
Superfamily -oidea (e.g., Canoidea) |
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-idae |
Family -idae (e.g., Canidae) |
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-inae |
Subfamily (e.g., Caninae) |
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Clade/ monophyletic group |
A group of species that contains a common ancestor, all of its descendents and nothing else. |
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Outgroup |
A taxon outside the group of interest. All the members of the group of interest are more closely related to each other than they are to the outgroup. |
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Sister groups |
Two clades that are each others closest relatives. |
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Paraphyletic |
a group is said to be paraphyletic if it consists of all the descendants of the last common ancestor of the group's membersminus a small number of monophyletic groups of descendants, typically just one or two such groups. Such a group is said to be paraphyletic with respect to the excluded groups. For example, the group of reptiles, as traditionally defined, is paraphyletic with respect to the mammals and birds: it contains the last common ancestor of the reptiles—including the extant reptiles as well as the extinct mammal-like reptiles—along with all descendants of that ancestor except for mammals and birds. Other commonly recognized paraphyletic groups include fish and lizards. |
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Polyphyletic |
Descendents of unrelated ancestors; does not include the common ancestor of at least two taxa; taxa are grouped together because of convergent evolution (or anything not covered by monophyletic or paraphyletic) |
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Character (or trait) |
Any discrete feature or attribute that exhibits variation. |
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Character state |
Expression of a particular character (e.g., presence, absence) |
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Ingroup |
Group of organisms beings studied |
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Character polarity |
Direction of evolutionary change in a character |
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Primitive character (plesiomorphy) |
Character state is primitive or "generalized" (shared by both the ingroup and outgroup) |
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Derived character (apomorphy) |
Character state is advanced or "specialized" (differs from outgroup) |
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Synapomorphy |
Derived trait shared by 2 or more groups |
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Homologous characters |
Character inherited from a common ancestor
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Analogous characters |
Similar function, but arose independently |
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homoplasy |
Means similarity in appearance but not in origin (convergence).
Similarity in species of different ancestors, which is the result of convergent evolution. Features or parts that look alike but do not share function or ancestry. |
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divergent evolution |
the opposite of convergent evolution, whereby related species evolve different traits. |
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homology |
means similarity in origin (implying a common ancestor) |
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Analogy |
Means similarity in function but not in origin. Convergent evolution creates analogous structures. |
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Convergent evolution |
Convergent evolution describes the independent evolution of similar features in species of different lineages. Convergent evolution creates analogous structures that have similar form or function, but that were not present in the last common ancestor of those groups. The cladistic term for the same phenomenon is homoplasy, from Greek for same form. The recurrent evolution of flight is a classic example of convergent evolution. Flying insects, birds, and bats have all evolved the capacity of flight independently. They have "converged" on this useful trait. |
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ecomorph |
Another term used to describe convergence. Ecomorphs are distantly related taxa with similar morphologies that occupy similar niches.
Ecomorphs typically are similar in dietary preferences, feeding adaptations, and/or locomotor adapatations. |
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Eutheria |
Placentalia |
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Metatheria |
Marsupials |
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Prototheria |
Monotremes |
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Oviparous |
(of a bird, etc.) producing young by means of eggs that are hatched after they have been laid by the parent. |
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Prehensile |
(chiefly of an animal's limb or tail) capable of grasping. |
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marsupium |
a marsupial is born very early in its development and completes development while nursing within a maternal pouch called a marsupium. |
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epiphysis |
Epiphyses are a feature of determinate growth in mammals.
The epiphysis is the rounded end of a long bone, at its joint with adjacent bone(s). Between the epiphysis and diaphysis lies the epiphyseal line (growth plate). At the joint, the epiphysis is covered with articular cartilage.
At maturity the growth plate ossifies with diaphysis (shaft) and growth stops. |
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Heterodont dentition |
Is an animal which possesses more than a single tooth morphology. Incisors, canines, premolars, molars. |
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eccrine gland (merocrine ) |
Sweat gland: +produce a watery secretion with little organic content - function as sweat glands in humans
+in most mammals, restricted to soles of the feet, tail and areas that contact surfaces to improve adhesion |
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sebaceous gland (halocrine) |
+over entire body associated with hair follicles +produce oily lubricant sebum that lubricates and waterproofs the hair |
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apocrine glands |
+type of gland in which the apical part of the secretory cell breaks down in the process +secretions used in chemical communication, for marking territories, warning, defense |
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horns |
+like those of sheep and cattle, are hollow sheaths of keratinized epidermis with a core of bone. +found in both sexes, grow continuously, and are not shed. |
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antlers |
like those of deer, are branched, composed of solid bone, shed annually +during growth, they have a highly vascular soft skin called velvet covering them. +usually only males have antlers (both sexes of caribou have antlers) |
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tooth crown |
Above the alveolus (tooth socket) |
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tooth root |
in alveolus (socket), below the gum line |
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enamel |
Outer layer of tooth. 97% hydroxyapatite, 3% organics (ectodermal origin) |
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Dentine |
Inner layer, 70% hydroxyapatite, 30% organics (dermal origin) |
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Cementum |
Spongy, bone-like material; holds tooth to socket. |
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Pulp cavity |
Within the dentine, holds blood vessels and nerves |
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Incisors |
+anterior (uppers occur on premaxilla) +structurally simple with a single root +have multiple functions in different mammals +sometimes they are modified as tusks (elephants and narwhals) |
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Anterior |
nearer the front, especially situated in the front of the body or nearer to the head. |
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premaxilla |
a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. |
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Canines |
+longer, conical teeth used for grasping +unicuspid +have a single root +never more than 1 pair of upper and lower canines +sometimes modified as tusks (walrus and pig)
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Premolars |
+Cheek teeth that have deciduous predecessors (i.e. milk dentition). +have 2 roots +can be unicuspid +used for grinding food
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molariform teeth |
squarish teeth used for grinding. |
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molars |
+cheek teeth that do not have deciduous predecessors +have 3 roots +multicuspid |
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deciduous teeth |
denoting the milk teeth of a mammal, which are shed after a time. |
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homodont dentitions |
homodont dentition refers to a set of teeth that possess the same tooth morphology. |
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Edentulous dentitions |
edentates (without permanent teeth).
Organisms that never possessed teeth can also be described as edentulous, such as members of the former zoological classificationorder of Edentata, which included anteaters and sloths, all of which possess no anterior teeth and either no or poorly developedposterior teeth. |
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posterior |
further back in position; of or nearer the rear or hind end, especially of the body or a part of it. |
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diastema |
is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. |
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diphyodont |
any animal with two successive sets of teeth, initially the "deciduous" set and consecutively the "permanent" set. Most mammals are diphyodonts as to chew their food they need a strong, durable and complete set of teeth. |
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polyphyodont |
any animal whose teeth are continuously replaced. |
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monophyodont |
Some animals develop only one set of teeth |
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teeth cones |
Individual cusps |
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buccal |
of or relating to the mouth. |
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lingual |
relating to, near, or on the side toward the tongue. |
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distal |
situated away from the center of the body or from the point of attachment. |
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mesial |
of, in, or directed toward the middle line of a body. |
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cingulum |
A shelf-like ridge around the outside of an upper molar |
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cingulid |
a shelf-like ridge around the outside of an upper molar |
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-id (tooth anatomy) |
Added to the name of a cusp indicates that it is part of a tooth in the lower jaw.
Ex: protoconid
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-cone (tooth anatomy) |
Added to the name of a cusp indicates that it is part of the upper jaw |
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tribosphenic molar |
The molar design that is considered one of the most important characteristics of mammals is a three-cusped shape.
Upper molars look like three-pointed mountain ranges; lower molars look like two peaks with a third off to the side.
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Trigon |
Triangle formed by the paracone, metacone, and protocone with the apex of the triangle on lingual side.
-points puncture - crests shear - protocone and talonid function together to crush and grind |
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hypsodont |
There is a lot of enamel and dentine above the gum line and the top of the pulp.
Dentition is characterized by high-crowned teeth and enamel which extends past the gum line. This provides extra material for wear and tear. Some examples of animals with hypsodont dentition are cows and horses; all animals that feed on gritty, fibrous material. |
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brachydont |
The opposite condition, low-crowned teeth, is termed brachydont. Human teeth are brachydont. |
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bunodont |
The cusps, instead of being sharp peaks, are rounded. The entire tooth is covered in enamel.
In bunodont molars the cusps are low and rounded hills rather than sharp peaks. They are most common among omnivores such as pigs, bears and humans. Bunodont molars are effective crushing devices and often basically quadrate in shape. |
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quadrate |
Quadrate molars have an additional fourth cusp on the lingual (tongue) side called the hypocone, located posterior to the protocone. Quadrate molars appeared early in mammal evolution and are present in many species, including hedgehogs, raccoons, and many primates including humans. There may be a fifth cusp.
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Lophodont teeth |
The tooth has a few ridges, perpendicular to the jaw. (elephants are named after this characteristic)
Have elongated ridges called lophs that run between cusps. Lophs are oriented between the labial and lingual parts of the tooth.
The molars and premolars of tapirs (Tapiridae), manatees (Trichechidae), and many rodents are lophodont. |
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Loxodont |
The tooth has many parallel oblique ridges on its surface.
Extreme lophodonty is seen is modern elephants (family Elephantidae) and some rodents. In these forms, the teeth look like an old-fashioned washboard. |
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Selenodont |
The tooth has a crescent-shaped ridge or ridges.
Another means of increasing the number and size of enamel cutting surfaces is to elongate the primary cusps in an anterior-posterior direction.
The teeth are deer and cattle are selenodont. |
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Carnassial teeth |
The fourth upper premolar and first lower molar in the jaws of many (but not all!) modern Carnivora are enlarged and bladelike. |
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fossa |
temporal openings in the skull, used to facilitate jaw muscle attachment. Used to distinguish the anapsids, synapsids, diapsids. |
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temporalis muscle |
attached to braincase, generates up/down jaw movement. |
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masseter |
attached to zygomatic arch, allows chewing in side/ side direction. |
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Therapsids |
+mammal-like reptiles +Advanced synapsids which led to modern mammals. |
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Synapsids |
Synapsids (Greek, 'fused arch'), synonymous with theropsids (Greek, 'beast-face'), are a group of animals that includes mammals and every animal more closely related to mammals than to other living amniotes.
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Sauropsids |
Sauropsida ("lizard faces") is a group of amniotes that includes all existing reptiles and birds and their fossil ancestors. Sauropsida is distinguished from Synapsida, which includes mammals and their fossil ancestors. |
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Pelycosauria |
+Primitive synapsids with 3 suborders. +Permian (290-250 MYA)
Ex: Dimetrodon |
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Cynodonts |
family: tritheledontidae
Precursors to modern mammals and their extinct close relatives. They were one of the most diverse groups of therapsids. They are named after their dog-like teeth. |
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Secondary Palate |
The medial extension of the maxillary (m) and palatine (p) bones forms a secondary palate, which allows for complete separation of mouth and nasal sinus, and allows for chewing and breathing at same time. |
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What is a mammal? |
A synapsid with a dentary-squamosal jaw articulation. (Reptiles have a quadrate-articular articulation).
As the jaw was remodeled, two of the bones that formerly made up the jaw joint were incorporated into the mammalian middle ear. |
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Mammary gland |
A transformed sweat gland, closely related to apocrine sweat glands.
-development of lactation would have to be associated with the development of the secondary palate so breathing and nursing could occur simultaneously -deciduous dentition likely evolved with nursing -the resultant close bond with offspring relates to increased behavioral development |
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Hadrocodium wui |
An extinct basal mammal species that lived 195 MYA in what is now China. Hadrocodium was 3.2 cm (1.4 in) in length (2 grams), and was one of the smallest mammals of either the Mesozoic or Cenozoic. |
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Liaoconodon hui |
Liaoconodon hui, fills the gap between the basal, early mammaliforms like Morganucodon, where the middle ear bones are decoupled from the lower jaw, as had been predicted, but were held in place by an ossified cartilage that rested in a groove on the lower jaw
The specimen shows the bones associated with hearing in mammals— the malleus, incus, and ectotympanic— decoupled from the lower jaw, as had been predicted, but remain linked to the jaw by the ossified Meckel's cartilage that rests in the groove on the lower jaw.
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basal |
primitive, ancestral |
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Teinolophos |
The earliest known monotreme is Teinolophos, which lived about 123 MYA in Australia.
Recent analysis suggest that it was not a basal (primitive, ancestral) monotreme but a full-fledged platypus, and that therefore that the platypus and echidna lineages diverged considerably earlier and that obviously basal monotremes were even earlier. |
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anapsids |
a reptile of a group characterized by the lack of temporal openings in the skull, including the turtles and their relatives. |
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diapsids |
a reptile of a large group characterized by the presence of two temporal openings in the skull, including the lizards, snakes, crocodiles, dinosaurs, and pterosaurs. |
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Repenomamus giganticus |
Was a large Triconodont more than 1 m (39 in) long and weighed about 12–14 kg (26–31 lb) and fed on young dinosaurs.
These finds are considered important, because they expand the ecological niches known to be inhabited by mammals during the 150 million year reign of the dinosaurs. |
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Multituberculates |
• the most diverse and numerous of the Mesozoic mammals • first mammalian herbivore • over 200 species are known, some as small as mice, the largest the size of beavers. • multituberculates are only known from the northern hemisphere coexisted with placental mammals for over 70 million years longest lasting (120 million years) of any mammalian order, extinct in Oligocene •appearance of rodents in the late Paleocene probably led to their extinction |
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Saltatorial |
+(especially of grasshoppers or their limbs) adapted for leaping. +jumpers, hoppers, or richochetal (bipedal)
This mode of locomotion is typically found in mammals living in open habitats. They typically have elongate, plantigrade hind feet, reduced forelimbs, and long tails. If they use their hindlimbs only and in a fast succession of hops, they are said to be ricochetal.
In animals that leap, like the wallaby, long rear limbs help the creature to hop across rugged terrain while the long tail helps with balance.
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Brachiation |
Brachiation (from "brachium", Latin for "arm"), or arm swinging, is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms.
The long arms of the gibbon show that the creature is well adapted to life in the trees
The long arms of the sloth show that they are also well adapted to life in the trees.
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Plantigrade |
(of a mammal) walking on the soles of the feet, like a human or a bear. |
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Palearctic |
Europe, North Africa (to Sahara), Asia (except India, Pakistan and SE Asia) and Middle East. |
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Nearctic |
Canada, USA, Mexico to tropics |
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Holarctic |
Palearctic plus Nearctic |
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endemic organism |
An organism that is exclusively native to a place or biota |
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neotropical |
Tropical Mexico south to South America, plus Antilles and south Florida |
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Afrotropic (Ethiopian) |
Madagascar, Africa south of Sahara, southern Arabian Peninsula |
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Indomalaya |
Pakistan, India, Southeast Asia, Phillipines, Indonesia, west of the Wallace Line (Sumatra, Java, Borneo) |
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Wallace Line |
The Wallace Line is a boundary that separates the zoogeographical regions of Indomalaya and Wallacea (a transitional zone between Asia and Australia).
A faunal boundary line drawn in 1859 by the British naturalist Alfred Russel Wallace that separates the ecozones of Asia and Wallacea, a transitional zone between Asia and Australia. West of the line are found organisms related to Asiatic species; to the east, a mixture of species of Asian and Australian origin is present. The line is named after Alfred Russel Wallace, who noticed this clear division during his travels through the East Indies in the 19th century. The line runs through Indonesia, between Borneo and Sulawesi (Celebes), and through theLombok Strait between Bali and Lombok. |
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Australasia |
Australia, New Guinea, Tasmania, Indonesian Islands east of the Wallace Line (Celebes, Timor, etc.) |
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Oceanic |
Oceans of the world and truly oceanic, isolated, small islands |
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Antarctica |
Antarctic continent and several island groups in the southern Atlantic and Indian Oceans.
The continent of Antarctica is so cold and dry that it has supported virtually no vascular plants for millions of years, and its flora presently consists of around lichens, mosses, liverworts, and terrestrial and aquatic algal species, which live on the areas of exposed rock and soil around the shore of the continent. Several species of mammals use it for breeding purposes. |
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Biogeography |
The study of how the spatial patterns of living things developed. |
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Intertropical Convergence Zone |
+Air rises when heated and releases moisture. Warm air rises in the Tropics and is replaced by air flowing towards the equator from north and south. The intertropical convergence zone is where these air masses come together.
+heavy rains usually fall in regions close to the intertropical convergence zone.
+This zone shifts latitudinally with the seasons, resulting in patterns of rainy and dry seasons. |
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Rain Shadow |
A rain shadow is a dry area on the lee side of a mountainous area (away from the wind). The mountains block the passage of rain-producing weather systems and cast a "shadow" of dryness behind them.
As shown by the diagram to the right, the incoming warm and moist air is drawn by the prevailing winds towards the top of the mountains, where it condenses and precipitates before it crosses the top. The air, without much moisture left, advances behind the mountains creating a drier side called the "rain shadow". |
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Biome |
Major ecosystem types based on the structure of the dominant vegetation. |
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Tundra |
The tundra biome is found in the Arctic and high on mountains.
A type of biome where the tree growth is hindered by low temperatures and short growing seasons. n tundra, the vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra regions. |
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Permafrost |
Permanently frozen soil that underlies tundra vegetation. Lowland Arctic tundra is very wet because water cannot drain through the permafrost. |
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tropical alpine tundra |
is not underlain by permafrost, so photosynthesis and other biological activities continue throughout the year and more plant forms are present. |
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alpine |
of or relating to high mountains. |
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Boreal Forest |
+Biome is found south of the tundra biome and at lower elevations on temperate-zone mountains. +winters are long and cold, while summers are short and warm. +the short summer favors trees with evergreen leaves. +boreal forests have only a few tree species. |
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temperate deciduous forest |
+biome is found in eastern North America, eastern Asia, and western Europe. +temperatures fluctuate dramatically from season to season. +precipitation is evenly distributed throughout the year. +deciduous trees lose their leaves during the winter. +many more tree species are present relative to boreal forests. |
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temperate grassland |
+Biome found in many parts of the world, all of which are relatively dry much of the year. +most grasslands have hot summers and cold winters +grasslands are structurally simple, but they are rich in species of perennial grasses, sedges, and forbs. +grassland plants are adapted to grazing and fire +most of the grassland biome has been converted to agriculture. |
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Cold desert |
+Biome is found in dry regions at middle to high latitudes +cold deserts are also found at high altitudes in the rain shadows of mountain ranges +seasonal temperatures vary greatly +cold deserts are dominated by a few species of low-growing shrubs
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Hot desert |
+The hot desert biome is found in two belts, centered around 30 degrees north and 30 degrees south latitudes. +Central Australia and the middle of the Sahara Desert are the driest regions within the biome. +Except in the driest regions, hot deserts have richer and more diverse vegetation than cold deserts do. +Succulent plants that store large quantities of water in their stems are common. Annual plants germinate and grow when rain falls. |
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Chaparral |
+Biome is found on the west sides of continents at moderate latitudes, where cool ocean waters flow offshore. +The Mediterranean region of Europe, coastal California, and central Chile are examples of chaparral. +Low-growing shrubs and trees with evergreen leaves are the most common plants in chaparral. The vegetation is adapted to periodic fires. +Large populations of small seed-eating rodents are present in the biome.
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Thorn Forests |
+Thorn forests are found on the equatorial sides of hot deserts. The climate is semi-arid with little or no rain in winter, but sometimes heavy rain in summer. +The dominant plants are spiny shrubs and small trees. Acacia is common.
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Savannas |
+Savannas are found in dry tropical and subtropical regions of Africa, South America, and Australia. +The savanna biome is characterized by its vast expanses of grassland and scattered trees, and by huge numbers of grazing and browsing mammals.
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tropical deciduous forest |
+The tropical deciduous forest biome is found closer to the equator relative to thorn forests and has a long summer rainy season. +Species richness is moderate for plants and high across all other categories, including mammals, birds, reptiles, and amphibians. +The tropical deciduous forest biome has some of the best soils in the tropics for agriculture. Most of it has been cleared. |
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Tropical Evergreen Forest |
+Tropical evergreen forests are found in equatorial regions where total rainfall exceeds 250 cm annually. +The biome is the richest on Earth in both plant and animal species. +Overall productivity of tropical evergreen forests is the highest among terrestrial ecological communities. There are many epiphytes, plants that grow on other plants and derive nutrients and moisture from air and water. |
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epiphyte |
a plant that grows on another plant but is not parasitic, such as the numerous ferns, bromeliads, air plants, and orchids growing on tree trunks in tropical rain forests. |
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Pangaea |
In the early Mesozoic era, 200 MYA, continents formed a single giant landmass called Pangaea. |
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Laurasia |
Laurasia was the northernmost of two supercontinents (the other being Gondwana) that formed part of the Pangaea supercontinent from approximately 300 to 200 million years ago (Mya). It separated from Gondwana 200 to 180 Mya (beginning in the late Triassic period) during the breakup of Pangaea, drifting further north after the split. |
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Gondwana |
Gondwana also Gondwanaland, is the name given to the more southerly of twosupercontinents (the other being Laurasia) that were part of the Pangaea supercontinent that existed from approximately 510 to 180 million years ago (Mya). Gondwana formed prior to Pangaea, then became part of Pangaea, and finally broke up after the break up of Pangaea. |
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Xeric mammals |
Desert Mammals. |
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Geomorphic factors |
Land form factors |
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Edaphic factors |
Abiotic factors, related to soil characteristics, which affect plant growth. +Sandy soils hold less water +high organic matter in soils supports more plant species +prairie grassland can build fertile soil
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Geographic disturbances |
fire, flood, volcanic eruptions, storm waves, high winds, etc. |
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Cosmopolitan species |
distributed very widely |
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Disjunction |
one or more closely related species found in widely separated regions |
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Eustatic |
relating to or characterized by worldwide change of sea level |
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Bergmann's Rule |
A rule that correlates latitude with body mass in animals.
It states that within a species, body mass increases with latitude and colder climate, or that within closely related species one would expect the larger species to be found at the higher latitude. |
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Allen's Rule |
States that the extremities of animals are relatively shorter in the cooler parts of a species' range than in the warmer parts.
Allen’s Rule showing ear length in rabbits and foxes where the animal on the left occurs in a hot desert habitat and the one on the right occurs in a cold tundra environment |
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Foster's Rule (also known as the island rule) |
States that members of a species get smaller or bigger depending on the resources available in the environment.
This is the core of the study of island biogeography. For example, it is known that pygmy mammoths evolved from normal mammoths on small islands. Similar evolutionary paths have been observed in elephants, hippopotamuses, deer, and humans (Homo floresiensis). |
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Integument |
1. Integument:
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Underfur |
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Guard hair |
the outer layer consisting of longer, coarser, straight shafts of hair that stick out through the underfur. This is usually the visible layer for most mammals and contains most of the pigmentation. It protects the underfur from outside factors, such as rain, and is thus often water-repellent.
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awn hair |
A third layer, awn hair, may also exist. It is intermediate between the two others |
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catastrophic molt |
elephant seals have a “catastrophic molt” - everything comes off, including the dermis |
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leukemism |
pigmentation and molts allow mammals to be different colors in different seasons
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albinism |
lack of pigment results in albinism - recessive gene - blocks pigment formation (not the same as leukemism) |
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melanism |
excess of black pigment is melanism |
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vibrissae |
Sensory hairs on snouts, other parts of head. They are incorrectly called whiskers. |
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Quills |
Defensive structures in porcupines, hedgehogs, echidnas. |
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unguis/subunguis/ claws |
The unguis is the outside hard layer, which has keratin fibers arranged perpendicular to the direction of growth and in layers at an angle.
The subunguis is the soft, flaky layer, and the grain is parallel to the direction of growth.
The unguis grows outward from the nail matrix at the base of the unguis and the subunguis grows thicker while traveling across the nail bed.
In claws (A), the unguis grows outward faster than the subunguis to make a curve and the thinner sides of the claw wear away faster than their thicker middle, making a more or less sharp point.
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Claws |
Claws are used to catch and hold prey in carnivorous mammals such as cats and dogs, but may also be used for such purposes as digging, climbing trees, etc, in those and other species. |
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nail |
A nail is homologous to a claw but is flatter and has a curved edge instead of a point. |
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hoof |
A nail that is big enough to bear weight is called a hoof. |
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toilet-claw |
In most primates, the nail only has the unguis; the subunguis has disappeared.
However, in prosimian primates the subunguis has redeveloped to make a claw-like structure. These aren’t actual claws, but instead the unguis appears normal along with a thick growth of subunguis.
This toilet-claw is used for grooming.
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artiodactyls |
Have two main hooves on each foot, together called a cloven hoof. Most of these cloven hoofed animals also have two smaller hoofs called dew-claws a little further up the leg--these are not normally used for walking. |
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Perissodactyls |
Odd-toed ungulates. Some have one hoof on each foot (equids); others (including rhinos, tapirs) have three hooves. |
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Axial Skeleton |
Composed of 5 parts: +the skull +the ossicles of the middle ear +the hyoid bones of the throat +the rib cage +the vertebral column |
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Superior |
further above or out; higher in position. |
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Lateral |
of, at, toward, or from the side or sides. |
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Ossicle |
a very small bone, especially one of those in the middle ear. |
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Hyoid bone |
a U-shaped bone in the neck that supports the tongue. |
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Costal |
of or relating to the ribs. |
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foreamen |
an opening, hole, or passage, especially in a bone. |
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pedicle |
a small stalk-like structure connecting an organ or other part to the human or animal body. |
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lamina |
a thin layer, plate, or scale of sedimentary rock, organic tissue, or other material. |
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cervical |
of or relating to the neck. |
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lumbar |
relating to the lower part of the back. |
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thoracic vertebrae |
Thoracic vertebrae compose the middle segment of the vertebral column, between the cervical vertebrae and thelumbar vertebrae. |
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Sacrum |
a triangular bone in the lower back formed from fused vertebrae and situated between the two hipbones of the pelvis. |
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Dorsal |
of, on, or relating to the upper side or back of an animal, plant, or organ. |
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Caudal |
of or like a tail. at or near the tail or the posterior part of the body. |
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Sternum |
Breast bone. In bats, the sternum is keeled (to give a larger area for muscle attachment) who need to flap their wings, and in many digging species who also need large muscles to work their forelimbs. |
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forelimb |
either of the front limbs of an animal. |
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hindlimb |
either of the back limbs of an animal. |
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pectoral |
of or relating to the breast or chest. |
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pelvic |
+the large bony structure near the base of the spine to which the hind limbs or legs are attached in humans and many other vertebrates. |
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pectoral girdle |
The pectoral girdle or shoulder girdle is the set of bones which connects the upper limb to the axial skeleton on each side. It consists of the clavicle and scapula in humans and, in those species with three bones in the pectoral girdle, the coracoid. Somemammalian species (e.g. the dog and the horse) have only the scapula. |
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Scapula |
Shoulder blade |
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Clavicle |
Long bone that serves as a strut between the scapula and the sternum. It is the only long bone in the body that lies horizontally. |
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The pelvic girdle |
Made up of 3 bones: the ilium, ischium, and pubis (=inominate). At the junction of these three bones is the socket (acetabulum) for the hind limb.
Unlike the pectoral girdle, the pelvic girdle is firmly attached to the spine, by a bony fusion between the ilium and sacral vertebrae. |
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Digitigrade |
Species that walk with most of the length of their digits, but not the soles of their feet in contact with the ground. Dogs and cats are an example. |
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Unguligrade |
Species walk on their toes, often on hooves. Deer and horses are an example. |
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Scansorial |
relating to, capable of, or adapted for climbing |
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Volant |
True Flight.
Bats are the only truly flying mammals – volant. Only with active flight have the resources of the aerial habitat been successfully exploited.
Bat bones tend to be light and slender. Bats are like birds in that they have reduced bones (ulna and fibula are shortened and thin. Bat also have a keel on their sternum for muscle attachment. Bat wing is supported by the arm and four highly elongated fingers (chiroptera = “hand-wing”)
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Glissant |
+Arboreal Gliders
+Mammals belonging to several groups (colugos, marsupials, rodents) are adapted for gliding – glissant. A gliding habit is frequently accompanied by scansorial (climbing) locomotion.
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Graviportal |
Of an animal, physically adapted only for moving slowly over land, due to a high body weight; examples include giant tortoises. |
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Cursorial |
Having limbs adapted for running.
Animals that run rapidly and for long distances.
Cheetah: Elongated back limbs, long feet bones and a highly flexible spine have made the cheetah the fastest land mammal. |
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ricochetal |
Animals that use their hindlimbs only and in a fast succession of hops (Kangaroos). |
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Arboreal |
Animals that scansorial and spend most of their lives in the trees.
Well-adapted arboreal mammals frequently are plantigrade, five-toed, and equipped with highly mobile limbs. Some species have a prehensile tail, which is used like a fifth hand. |
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pachyostosis |
deep waders: walk on substrate beneath surface of water
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stride |
A full cycle of motion of a running or walking mammal is called a stride. An animal's speed is the product of its stride length times rate.
There are two primary ways of increasing the speed of running, increasing stride length or increasing stride rate.
Some animals are clearly specialized to increase speed through increasing stride length; the giraffe is an extreme example.
Others move rapidly by having a very fast stride rate; these would include, for example, shrews and voles.
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