Author Archives: Brian Hopkins

The tracing of a character with different states onto a cladogram.  This enables the identification of evolutionary changes in the character and the reconstruction of the ancestral pattern.  See Character, Cladogram, Phylogeny

Those abilities and behaviors that are typical of the species.  For example, walking is a phylogenetic ability of humans. Ontogenetic abilities are those supported by the culture.  An example would be a specific dance step (e.g., a polka) that is unique to the individual or culture, but not seen in all humans.  See Ontogenetic skills, …

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The time scale required for speciation to occur and thus consisting of time measured in units of a million years. See Developmental (or ontogenetic) time, Phylogeny, Speciation

New species originate in a small, isolated peripheryof ancestor’s geographical range (allopatric speciation) See Biological evolution, Constraint, Founder effect (or principle), Genetic drift (or random walk), Jacob-Monod operon model, Macroevolution (or horizontal evolution) and microevolution (or vertical evolution), Modern synthesis, Mutation (biology), Palaeontology, Phyletic, Phylogeny, Regulator genes (or regulatory), Speciation, Species, Structural genes, Theory of …

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A term applied to a group of species with a line of direct descent (i.e., no branching). See Constraint, Phyletic gradualism and punctuated equilbrium, Phylogeny, Species

Reflexive locomotion toward (‘positive’) or away (‘negative’) fromlight in phototropic organisms (e.g., phototropic eukaryotes and prokaryotes) along a light gradientor vector.  In such organisms, photoaxisis mediated by a pair of very simple eyes or eyespots involving type I sensory rhodopsin photoreceptors.  See Cones and rods, Eurkaryote cell (or organism), Prokaryote cell (or organism)

The addition of phosphate to an organic compound such as protein through the action of the enzyme phosphylase that triggers the glycogen molecule to form glucose.  It can change the activity of protein and is probably the most common mechanism for altering the biological function of proteins in cells and thus for transferring energy between …

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Also called phosphatides, they are compounds of various phosphorous-containing lipids that are composed of a glycerol molecule bonded to two fatty acid molecules, and a phosphate group with a nitrogen-containing component.  The phospholipids lecithins and sphingomyelin facilitate the maturation of the fetal lungs before birth.  Those belonging to cell membranes form a two-molecule thick sheet …

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A salt or ester of phosphoric acid.  While commonly associated with fertilisers, they are involved in many biochemical processes, often as part of complex molecules, such as adenosine triphosphate.  An ester is a compound formed by the reaction of an acid with an alcohol and also includes the fats and oils that are esters of …

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A domain of speech sciences (viz., phonology) thatfocuses on the freedoms and restrictions in a given language on permissible combinations ofvowels and consonants in syllables and words (e.g, types of consonantcombinations for clusters in English such that mb never occurs, but does so in Irish).  All told, language-related phonotatics dictate which sounds precede and follow …

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