Calcaneum / Calcaneal
The bone that forms the heel or rear part of the hindfoot. Thus, calcaneal
1. A crust or salt or lime on the surface of maetrials such as bone or stone after thay have been buried or exposed to moisture for an extended time.
2. An apaque found in layers at or near the surface of stony soils in arid or semiarid regions.
Spongy bone; a type of bone having tissues that are not closely packed. [Compare: compact bone]
A tough, shieldlike layer of material covering all or part of the dorsal surface of an animal.
Carnivore / Carnivorous
An animal whose diet consists exclusively or mainly of the flesh of other animals. Thus, carnivorous
Either of the two main arteries carrying blood from the heart to the head.
1. Describing or relating to the wrist, or an structure analogous to the wrist.
2. The bone of the wrist // Metacarpus = middelhand
Computerized axial tomofraphy scan, the technique of using a computer to process data from a tomograph in order to display a reconstruction of an organism\'s body in cross section. See also tomography
A texture found in metamorphic rocks in which brittle minerals have been broken, crushed, and flattened during shearing.
1. The historic view, now generally rejected, that the observable differences in form and distribution of fossils were caused by cataclysms that no longer occur, followed by new periods of creation. [Compare Uniformitarianism].
2. The current view that certain mass extinctions were the result of such cataclysmic events as the impact of very large meteorites.
Of the tail. For example, the vertebrae of the tail are called caudal vertebrae In anatomy, describing or relating to the tail
A thin layer of calcified tissue that covers the enamel layer at the root of a tooth, aiding in holding the tooth in place in its socket
The exposed core of uplifted rocks in complex meteorite impact craters. The central peak material typically shows evidence of intense fracturing, faulting, and shock metamorphism.
Plural, centra, in anatomy, the body of a vertebra as opposed to the arches. n., pl. centra, abbrev. cent the large, round area of a vertebra
Cephalopod / Cephalopoda
One of a group of marine invertebrate animals (Cephalopoda) including the squid, octopus, and nautilus.
Of the neck. For example, the vertebrae of the neck are called cervical vertebrae. In anatomy, describing or relating to the neck or a neck-shaped region.
Any distinctive feature or trait of an organism, or any difference among organisms, that can be used to construct a classification or to estimate phylogeny.
Any of the range of expressions or conditions of a particular character.
Or haemal spine, a process projecting downwards from a vertebra, usually of the tail
The opening between the nasal cavity and the pharynx
The outermost fetal membrane lying outside the embryo itself.
Chronostratigraphy / Chronostratigraphic
1. The study of geologic history based on a analysis of the age of distinctive rock layers (or fossil aggregations) and their time sequence.
2. A set of descriptive time units derived from such a study. Thus, chronostratigraphic
A branch of the evolutionary tree; a taxon (group of arganisms) made up of a common ancestor and all of its related descendants. See also monophyletic
Cladistics / Cladism
A method of classifying organisms in which hypotheses about evolutionary relationships are the basis for classification, and the criterion for establishing groups of organisms is the recency of common ancestry, based on the identification of shared, derived characters. Also, cladism
The process of developing clades; the formation of new lineages.
A branching diagram of the distributions of synapomorphies among taxa, and hence the degree of relation among species, based on shared characters derived from a common ancestor.
The bone joining the breastbone to the shoulder blade; the collarbone
The study of climate, especially its effects on living organisms.
1. A group of genetically identical cells derived from a single parent cell.
2. A sequence of DNA material from one organism, artifically inserted into another organism.
3. In popular use, an organism that has been artifically brought to live by the extraction of a cell or cells from another living (or dead) organism.
4. To produce a new, genetically identical organism in this manner.
An assemblage of fossils
A popular term describing an organism whose internal body remparature is relatively lower than that of a warm-blooded animal.
Collagen / Collagenous
A gelatinous protein that is present in all multicellar organisms, especially in connective tissue. Thus, collagenous.
The bone joining the nearest bone to the shoulder blade; the clavicle
A behavior pattern in which a large number of individuals of a single species congregate in the same limited area, as for breeding; observed in modern birds and mammals and also indicated in some dinosaurs.
One of the primitive icy bodies originating in the outer reaches of the solar system that are in elliptical orbits around the Sun. Near the Sun, the icy material vaporizes and streams off the comet, forming a glowing tail.
1. The hypothetical single species of organisms that two or more different species of organisms evolved from 2. in cladistics, a species that evolves into a clade
A type of bone having dense, closely packed tissue, with little interstitial space. Compare cancellous bone.
The simultaneous use of a limited resource by two ore more species, resluting in conflicting efforts by those species for continued survival.
In anatomy, a rounded projection at the end of a bone.
Describing or relating to species that belong to the same genus.
1. Tending to remain unchanged. 2. Specifically, showing a relatively low rate or extent of evolutionary change; similar to an ancestral group.
Describing or relating to individuals that belong to the same species.
The theory or phenomenon that the formation of the present continents resulted from the breakup and displacement of a single huge land mass over geologic time. See plate tectonics.
Convergent evolution / Convergence
An evolutionary change that produces similar characters in two or more distantly related forms, as a result of their common, but separate, adaptation to similar environmental conditions. Also convergence
A fossil composed of ancient animal fecal (waste) matter.
n., abbrev. co semicircular bone attached to the front of the scapula, a bone that extends from the upper ventral surface, of the scapula to the sternum in reptiles. In mammals, this bone is reduced to a bony process on the scapula.
A membrane bone on the upper side of the lower jaw, nearer to the back of the jaw and lacking teeth.
Having a worldwide or very wide distribution.
A mso-fareast-language:NL;mso-bidi-language:AR-SA\"> turtle carapace plate, which has a rib, attached to it
A term not recognized by the Code, formerly used for either syntype or paratype, but that should not now be used in zoological nomenclature.
The study of the physical structure of the cranium.
Cranium / Cranial
The skull, with the exception of the lower jaw, especially the portion of the skull that encloses and protects the brain, Thus cranial
The relatively stable portions of continents composed of shield areas and platform sediments. Typically cratons are bounded by tectonically active regions characterized by uplift, faulting, and volcanic activity.
A geological term denoting the interval of Earth history beginning around 144 million years ago and ending 65 million years ago.
A major stratigraphic boundary on Earth marking the end of the Mesozoic Era, best known as the age of the dinosaurs. The boundary is defined by a global extinction event that caused the abrupt demise of the majority of all life on Earth. Also known as the K-T boundary.
A group of organisms consisting of the last common ancestor of the group and all of the living descendants; e.g., Archosauria has been defined as a crown group including two extant groups of archosaurs, birds and crocodiles, plus their common fossil relatives.
The lower leg; the leg from the knee to the foot.
1. Not obvious or clear from the available evidence; uncertain or ambiguous.
2. Of an organism, marked or colored in such a way as to blend in with the surrounding environment.
Rock types made up of crystals or crystal fragments, such as metamorphic rocks that recrystallized in high-temperature or pressure environments, or igneous rocks that formed from cooling of a melt.
The scientific study of the formation and properties of crystals (i.e., solids that have a regularly repeating arrangement of atoms).
See Cat scan
1. Of limbs or digits, adapted for running.
2. Of an organism, able to move rapidly over the ground; having the behavior pattern of running. Compare graviportal
Any of the Cyades, an order of gynosperms (conebearing plants), typically having broad, underbranched stems with a crown of large, pinnate leaves at the end.
\"dog-toothed,\" as applied to mammals and some of their closest fossil relatives