A:

Aberrant: Deviating from the expected course, in relation to behavior, physical attributes, or other characteristics.

Abundism:  An animal that has markings that are more prolific than usual.  Also known as pseudo-melanism.  (IMAGE)

Adaptation:  A physical or behavioral characteristic that arose and evolved by natural selection to benefit a species, and improve a species' chances of survival and procreation.

Agonistic Behavior: Aggressive or defensive behavioral patterns, including threats, physical attack, dominance and submission, fighting, and appeasement.

Agouti:  A pattern on the individual hair shaft where the hair itself has bands of multiple color in alternating patters.  This is caused by the melanin production in the follicle of the hair being turned off and on sporadically throughout the growth of the hair shaft.   (IMAGE)

Albinism:  An albino individual, which completely lacks pigmentation in its fur, flesh, and eyes.  True mammalian albino individuals are white or pink with pinkish red eyes.  Albinism can also occur in patches over the body, known as a piebald pattern. Partial albinism is when the animal still retains some markings, though they may be faint. In snakes, they are still able to synthesize yellow and red pigments, so albino snakes have red and yellow markings, but lack the normal black pigmentation.  In fish, red markings are often preserved, as in the albino red-tailed shark (Labeo bicolor). White animals that retain most markings and have blue eyes are not albinos, but are leucistic (ex: White German Shepherd dogs, white lions, white or snow white tigers).  Tyrosinase-Negative Albinism:  An albino whose cells lack tyrosinase (an enzyme which synthesizes melanin), usually producing a pale yellowish or cream animal with pink-eyes.  Tyrosinase-Positive Albinism:  An albino not able to synthesize melanin, but able to synthesize tyrosinase, often resulting in a fawn or lavender (platinum) color. This ("partial albinism") is the most common form of albinism.

Allopatric: Species with non-overlapping geographic distribution. Often in reference to populations of the same species that are separated by geographic barriers such as rivers, oceans, mountain ranges, or islands.  The North American and Eurasian wolf subspecies are a good example.  This is how subspecies arise.

Alpine:  Region of high mountains.

Ambulatory: Able to walk.

Anal Gland: A scent gland located in the opening of the anus.

Anoestrus:  The period of time between active sexual behavior; between breeding seasons.

Anterior: Towards the front.

Aposematic: Warning coloration

Aquatic:  Living mostly or entirely in the water.

Arboreal:  An animal that lives or spends a great deal of time in the trees.

Artiodactyl: An ungulate with an even-number of toes on each foot (cattle, pigs, sheep).

Auditory Bulla:  Bony capsule enclosing the middle and inner ear.  Plural: bullae

B:

Baculum: A bony structure commonly found in the penis of mammals.  This os-penis, as it is often referred, serves to "lock" the mating pair in a copulatory tie.

Binomial Nomenclature: The standard system of giving an animal 2 names (Genus species).  Often called the scientific name, it consists of Latin and Greek words that in some way describe the animal.

Blastocyst:  The second stage of embryonic development, when the zygote begins to divide into multiple cells, clumped to one side of a hollow sphere.  This is formed before it implants itself to the uterine wall.

Boreal: Relating to the forests of the northern temperate zone, often dominated by coniferous trees.

C:

Canid:  Of or referring to the dog, canine; possessing traits similar to dogs; also, a member of the Canidae family.

Canine Teeth:  The long, pointed, cone-shapes teeth commonly found in carnivorous animals. Used for gripping prey, and delivering a killing bite.  (IMAGE)

Canoidea:  Also known as Arctoidea, the superfamily of animals with dog-like features (dogs, bears, weasels, and raccoons).

Carnassial:  Large, shear-like premolars that are found in the order Carnivora; used for shearing meat.  (IMAGE)

Carnivore:  Animals that feed almost exclusively on meat; also referring to animals of the order Carnivora.

Caudal:  Referring to the tail or rear end.

Caudal Gland:  A scent gland located on the base of the tail, often on the dorsal side.  Often referred to as a precaudal gland.

Cervical: When referring to the spine, the neck region.  Refers to the neck region of any organ or structure.

Chinchilla:  When referring to the hair coloration, means the hair lacks the normal agouti banding pattern, instead being solidly colored except at the tips.  Also known as the smoke coloration, especially in Persian cats. (IMAGE)

Chromatophore:  Cells responsible for holding pigmentation.  In plants, these are chloroplasts, which produce chlorophyll (green coloration). Animals have many different types of pigmentation cells, and can produce any number of compounds that produce color.  Xanthophores produce yellow pigment; erythrophores produce red pigment; melanophores produce melanin (black pigment). Two types of chromatophores are "colorless", unable to produce pigmentation, instead producing color by reflection of light off of the surface of purine crystals.  Iridophores are packed with large highly-reflective non-motile purine crystals, which produce a silvery iridescent reflection in fish, amphibians, and invertebrates; these give blue poison dart frogs frogs their color.  Leucophores contain small motile purine crystals, is often referred to as "white pigment".   Combinations of any number of these five pigment cells produce the variety of colors seen in the animal kingdom.  Pigmentation in some species, like the flamingo and goldfish, is not synthesized from pigment cells, but instead synthesized from food. The colors disappear when their diet lacks carotenoids.  Pigmentation of a chemical compound is often secondary to function, such as the red pigmentation hemoglobin in red blood cells.  Mammals only have melanophores, while other animals usually have more than one type of pigmentation cell.   More about pigmentation can be found here.

CITES: Convention on International Trade in Endangered Species. http://www.cites.org

Clavicle: Collarbone.

Coniferous Forest:  A forest containing mostly cone-bearing trees; evergreens.

Conspecific: Member of the same species.  Often refers to scientific names, such as when an animal is known by two scientific names, we say the two names are conspecific, or synonymous, with each other.  Also, when a species was previously thought to be its own separate species and was found to be actually a variation of another species, these two species are said to be conspecific.

Coronoid Process:  The coronoid process of the mandible is the triangular projection that fits into the zygomatic arch.  Provides attachment for the temporal muscles of the jaw. (IMAGE)

Cranial:  Referring to the head.

Crepuscular: Being active in the early dawn or twilight.

Cursorial: Having legs adapted for running (ie: cheetah)

D:

Deciduous teeth: Primary or "baby" teeth.

Deciduous Forest: A forest containing broad leafed trees that lose their leaves in the autumn. Example, maple or oak.

Delayed Implantation:  Where the fertilized ovum will sit in the fallopian tubes for an extended period of time before it implants itself in the uterus.  In most mammals, this is done almost instantaneously, but some mammals, like bears, procyonids, and some mustelids, the time is extended several months.

Dental Formula:  This is a numerical representation of the number of teeth in an animal's mouth.  This is represented by the number of a type of tooth in one quadrant of the mouth on the top, and one quadrant of the mouth on the bottom.  The number is multiplied by 2 to get the total number of teeth in the mouth.  For example,  the dental formula for a Eurasian river otter is:  I 3/3 C 1/1 P 4/3 M 1/2 x2 =36, where I is incisors, C is carnassials, P is premolars, and M is molars.

Dewclaw:  "thumbs"; the fifth inner digit present on the front paws of most carnivores.

Diestrus: The last stage of estrus, immediately following ovulation.  Progesterone is at is peak in this stage.  This stage is the period of sexual inactivity that follows ovulation, and characterized by the female being non-receptive.  Also known as the luteal phase.   If a female mammal is not mated, the cycle will return to the anestrous, or period of sexual and hormonal inactivity between estrus cycles.

Digit:  Finger or toe.

Digitigrade:  An animal that walks on its toes without the heel or hock touching the ground, like cats and dogs.  (IMAGE)

Dilution:  Washed out, sparse.  When referring to coloration, when the color is dull, almost pastel.

Dimorphism:  Two distinct forms in a species; most commonly "sexual dimorphism", which refers to the differences in the sexes.

Diphyodont:  The development of teeth come in two phases, the deciduous, or baby teeth, and the permanent, or adult teeth.

Diurnal: Being active during the day.

Dorsal:  The back (along the spine) of an animal.

E:

Endangered Species Act:  a legislation passed by the United States Congress in 1973, which grants legal protection for listed endangered and threatened species.

Endemic: Native to an area.

Erythristic: When the fur coloration of an animal is unusually red. Usually in reference to black pigmentation, like markings, but can apply to ground coloration as well.   (IMAGE)

Estrus:  The second stage of estrus when the female is receptive to mating.  This stage immediately precedes ovulation.  Progesterone is increasing in this stage, and estrogen levels decrease.  The luteinizing hormone peaks at this stage, and this is when ovulation occurs.  (also spelled 'oestrus')

Estrus Cycle:  The hormonally-controlled cycle in female mammals where the body prepares for mating and pregnancy.  The stages of estrus are: anestrus, proestrus, estrus, and diestrus.  Ovulation usually occurs between estrus and diestrus.  If not mated, females will revert back to the anestrus stage. (also spelled 'estrous cycle')

F:

Fecundity:  The birth rate, or however many offspring over the course of an animal's lifetime; not to be confused with litter size.

Felid: Of or referring to cats, feline; possessing traits similar to the cat; also, a member of the Felidae family.

Feloidea:  Also known as Aeluroidea, the superfamily of carnivores that have cat-like features (cats, hyenas, mongooses, civets).

Foramen: A hole or opening in bone that allows the passage of nerve bundles and blood vessels through bone.  Plural: foramina

Fossorial: Having legs adapted for digging (ie: mole)

Frugivorous: An animal that feeds mainly on fruits.

G:

Gestation Period:  Pregnancy.

Geologic Time Scale: List of eons, eras, periods, and epochs in time.  (VIEW CHART)

Gregarious: An animal that is very social and thrives in groups.

Guard Hairs:  The thick, hard hairs that carry the color of an animal's coat and provide protection.  (IMAGE)

H:

Hectare: Metric unit of measure that equals 100 ares (2.471 acres).

Herpestid:  Of or referring to the mongoose, herpestine; possessing traits similar to the mongooses; also a member of the Herpestidae family.

Hertz (Hz): One cycle per second.  Often used in reference to sound waves.

Home Range:  An individual animal's territory.

Horizontal: Side-to-side.

Hybrid:  An offspring of parents of two different species.

I:

Incisors:  The small teeth located at the very front of the mouth, used for gripping prey or bits of food.  (IMAGE)

Induced Ovulator:  A female mammal that will not ovulate unless stimulated to do so by mating.

IUCN: International Union for Conservation of Nature http://www.iucn.org

J:

Jacobson's Organ:  The vomeronasal organ, a secondary olfactory receptor found on the roof of the mouth in reptiles and carnivores.  It is used to detect certain chemicals in the air, such as pheromones.

K:

Keratin:  Tough, water-resistant protein found in the epidermal layer of the skin.  Comprises hair, hooves, nails, claws, beaks, etc.

L:

Lactation:  The production of milk.

Lagamorph: Rabbits and hares.

Lateral: Referring to the sides.

Leucistic:  An animal that is white or light in color that is not naturally so. Not albino, because the animals still have some pigmentation, such as markings, and have blue eyes, not red, like in albinos.  Leucistic individuals lack, or partially lack, chromatophores, the skin cells that are responsible for holding pigmentation. An example is the white tigers.  Snakes that are leucistic appear solid white, whereas albino snakes still retain red and yellow pigmentation. 

Litter: When a group of offspring are born at the same time, as a characteristic of the species.

Lumbar: Region of the lower back, between the thorax and the pelvis.

M:

Maltese:  When pigments dilute into a bluish color.

Mammae:  Mammary glands; teats; nipples.

Mandible: The lower jaw.

Maxilla:  The upper jaw.

Melanistic: An animal that is dark or black in color that is not typically so.  Felids display this trait frequently.  These animals are usually not pure black, as any markings can still be seen.  Examples: black leopard, black jaguar.

Molar:  The flattened teeth found at the back of the mouth that are used for grinding.  (IMAGE)

Mollusc:  Any animal in the Phylum Mollusca, including but not limited to snails, clams, and octopuses. (also: mollusk)

Monogamous: Having one mate at a time, often for a period of time.

Morphology:  Form and structure of an animal. also: Morphological.

Mustelid: Of or referring to the weasel family, musteline; possessing traits similar to the weasels; also a member of the Mustelidae family.

N:

Natal: Relating to birth

Neotony:  A process where the normal course of physical maturation is retarded, producing an animal that carries the appearance of a juvenile while still able to reach sexual maturity.  This often occurs to animals during domestication, such as the dog.

Niche: A species' functional role in an ecosystem. Examples: predator; pollinator; seed-disperser.

Nocturnal: Being active primarily during the night.

O:

Olfactory: Relating to scent.

Omnivorous: Eating both plant and animal matter.

Ovulation:  When a mature ovum ("egg") is released from the ovaries to be fertilized.

P:

Parturition: The act of giving birth.

Pectoral:  Referring to the chest area.

Pelage: Fur.

Pelvic:  Referring to the hip area.

Perianal: Near the anus.

Perianal gland/ Perineal gland:  The scent glands found near the genitals of civets and genets, often used for marking territory.

Perineal: Referring to the perineum, which is the region between the thighs; more specifically, between the genitals and anus.

Perissodactyl: An ungulate with an odd-number of toes on each foot (horse, rhino).

Piebald:  Having patches of white fur.

Piscivore:  Having a diet primarily of fish

Pinnae:  The flap of skin and cartilage that constitutes the outer ear in mammals.

Plantar:  The bottom of the foot.

Plantigrade:  An animal that walks on the entire sole of its feet, like humans or bears, where the heel touches the ground. (IMAGE)

Premolar:  The larger molars found behind the canine teeth.  (IMAGE)

Polyandrous: Female mates with more than one male in the mating season.

Polyestrus:  A female that comes into estrus more than once a year.

Polygamous:  Having more than one mate per breeding season.

Polygynous: Male mates with more than one female in the mating season.

Polymorphic: Having a variation within a species, ie: fur color.

Posterior: Towards the rear.

Poultry:  Birds; most often referrs to domestic fowl such as chickens and turkeys.

Procyonid:  Of or referring to the raccoon, procyonine; also, a member of the Procyonidae family.

Proestrus:  The first stage of estrus, also known as the follicular phase.  The female is not ready to mate in this stage, although interest by males increases. In this stage, the body is preparing for mating.  The ovarian follicle (or follicles) undergo maturation, the development of the endometrium occurs, and the vaginal mucosa thickens.   This stage is characterized by the beginning of an increase in progesterone, as well as a marked increase in estrogen.  Estrogen will continue to increase in production until the beginning of the estrus stage, when it will rapidly decline as it is replaced by progesterone.

Q:

Quadruped:  An animal that walks on all four legs.

R:

Recessive:  A gene that can be masked, or hidden, in the presence of a dominant gene.  This is how two brown-eyed parents can have a blue-eyed child.

Resilience:  The ability to recover from destructive events.

Rhinarium: The nose, specifically the area surrounding the nostrils

Riparian:  Vegetation growing on a river bank.

Rostrum:  The muzzle or snout.

S:

Sagittal Crest: Large, pointed structure found at the base of the skull that is used for anchoring the large jaw muscles. (IMAGE)

Scapula: Shoulder blade.

Sexual Dimorphism:  The distinct differences between the male and female of a species.  Often this is height and weight.  In birds, coloration is usually key.  In some animals it the presence or absence of a specific feature, like the mane in lions.

Species:  An animal, etc, that is genetically unique and only able to create fertile offspring with members of its own species.

Sternal:  On the belly.

Subcutaneous:  Just underneath the skin.

Subspecies:  A race of a species, often characterized by a specific geographic population or physical characteristics.  Example, the Arctic wolf and Mexican wolf are subspecies of the grey wolf (Canis lupus).  Subpsecies' names are written in what is called Trinomial Nomenclature (three names), as Genus species subspecies. Example: Canis lupus baileyi for the Mexican grey wolf.

Sympatric:  A geographic area where similar species coexist but do not interbreed.

Synonym: When referring to a taxonomic name synonym, it means the invalid, or alternate name for a species.  Many times, animals names get changed as they get reorganized, and as a result their former scientific names are no longer valid.  But many sources will still list these names so they are referred to as 'synonyms'. 

T:

Tapetum Lucidum:  A layer of cells on the retina of some mammals that reflects light back onto the retina, amplifying light in low-light conditions.

Taxon:  A unit of classification, such as Kingdom, Phylum, etc..

Taxonomy: The classification of organisms in a system that indicates relationship.  This includes the Kingdom, Phylum, Class, Order, Family, Genus and Species, and subsets thereof.   Names are usually in Latin or Greek or a combination of both.  Generally, an animal's scientific name is referred to by its genus and species name only, called Binomial Nomenclature (two names).  These names are in italics, with the genus capitalized and species in lowercase.  The scientific name is considered the standard, since it is the same no matter the locality, and since common names can be numerous and confusing.

Temporal Muscles:  The large muscles that work the jaw. (also, temporalis)

Terrestrial: Living primarily on the ground.

Territory:  A specific area occupied by an individual animal or population of animals

Thoracic: Pertaining to the chest/thorax.  When in reference to the spine, the vertebrae which carry the ribs.

Trunk:  The chest.

U:

Undercoat:  Fluffy, downy, crimped hairs that provide insulation.  There are hundreds of undercoat hairs in each guard hair follicle. (IMAGE)

Ungulate: Hoofed mammal.

Unguligrade:  Walking on the very tips of the toe, like deer.   (IMAGE)

Ursid:  Of or referring to the bear, ursine; possessing traits similar to bears; also, a member of the Ursidae family.

V:

Vector:  An animal responsible for the spread of a disease. This can be an animal extremely susceptible to the disease or a carrier of the disease (not affected).

Veld:  Open grassland in Africa

Ventral:  The belly-side of an animal.

Vertical:  Up-and-down.

Vestigial: A structure that is rudimentary (undeveloped) or degenerate

Vibrissae: Whiskers. The three main types of whiskers are mystical (muzzle), superciliary (above the eyes) and gular (throat).

Viverrid:  Of or referring to the civet, viverrine; possessing traits similar to civets; also, a member of the Viverridae family.

Vomeronasal Organ:  The Jacobsen's Organ

W:

Wean: When an animal starts to feed on food besides its mother's milk; an animal is fully weaned when it no longer depends on milk.

X:

Xanthic:  Having more yellow coloration to the fur than is typical.

Y:

Z:

Zoonosis:  A disease that can be transmitted from animals to humans, or vice-versa.  Example: Rabies.

Zygomatic Arch:  The cheekbones . (IMAGE)

Zygote: The first stage of embryonic development, consisting of the single fertilized ovum, just before it splits into two cells. After it starts to divide, it is referred to as a blastocyst.

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