Evolutionary Glossary

A (Back to Top)

Adaptation - Alteration in an organism’s behavioral and physiological trait either/or any structure that makes it fitter to survive in a given environment. Evolution by natural selection claims that organisms with traits that enable them to adapt to their environment better than others in the species will have a greater chance to survive, reproduce, and pass their genes on to the next generations. An adapted organism may not be so if the environment changes. Thus, it is a dynamic scenario with organisms have constantly to change with environmental change. [Evo-Ego Team].

Adaptive Radiation- An adaptive radiation is a burst of evolution, creating several new species out of a single parent species.This process results in the speciation and phenotypic adaptation of an selection of species exhibiting different morphological and physiological traits with which they can use a range of divergent environments. [404 page not found]

Allopatry - The biogeographical pattern in which two populations are geographically separated; their habitats do not overlap. [Sacrivzoa Team]

Apoptosis - Is the process of programmed cell death that may occurred in multicelular organisms.

Autapomorphy - A derived trait that is unique to a terminal group and not found in the ancestor of the group.

B (Back to Top)

Bats - Belonging to the group Chiroptera, bats are the most species-rich group of Mammalia, encompassing a total of 1200 species which represents 20% of all mammalian diversity. They are also the only mammals capable of true and sustained flight. [The Gotham Project].

Biogeography - The study of patterns of geographical distribution of plants and animals across Earth, and the changes in those distributions over time [The Disturbed Team].

C (Back to Top)

Cardiomyocytes - the cells of which cardiac muscle is composed of. [LUCA-The Jelly Team]

Carnivores - Organisms that have a diet based on meat. [The Gotham Project]

Cassava - Manihot esculenta ssp. esculenta, a eudicot in the plant family Euphorbiacea native to the southwestern Amazon basin, selected for its tuberous roots that accumulate large amounts of starch. [Team ecoevo]

Cellular senescence - A metabolically active form of irreversible growth arrest that halts the proliferation of ageing and/or damaged cells and, as a consequence, prevents the transmission of damage to daughter cells. [LUCA-the jelly team]

Character - An observed structure or behavior in organisms. In characters are used as common properties of different organisms and are regarded as being heritable and homologous. [Team ecoevo]

Character state - a variant form of a given phenotypic character (see also Character). For example, pink, red, yellow or white petals may be traits of flower petal color charcater. [Team ecoevo]

Cis regulatory elements - A noncoding DNA sequence near a protein coding region required for proper spatiotemporal expression of that gene, often containing binding sites for transcription factors. Often used interchangeably with enhancer (Futuyma, 2005). An example is the Iron response element in Eukaryote's RNA. Changes in cis-regulatory sequences are an important part of the genetic basis for adaptation. Some phenotypic changes are more likely to result from cis-regulatory mutations than from coding mutations. [Evo-Ego Team]

Clade - In a rooted tree, a clade is a group of branches that form a monophyletic group, what means they have a common ancestor that is not a common ancestor for any other branch in the tree. In an unrooted tree, a clade would be any group of taxa that can be separated from the rest by removing a single edge [The Disturbed Team].

Cladogram - A graphical representation of relationships among a set of taxa or qualitative data.

Cnidarian - Cnidarians are diploblastic Eumetazoa that possess radial symmetry, tentacles, stinging or adhesive structures called cnidae, an entodermally derived incomplete gastrovascular cavity and a middle layer (called mesenchyme, or mesoglea) derived primarily from the ectoderm. They lack cephalization, a centralized nervous system, and discrete respiratory, circulatory, and excretory organs. The phylum Cnidaria is a highly diverse assemblage that includes jelly-fish, sea anemones, corals, as well as many less familiar forms such as hydroids, sea fan, siphonophores, zoanthids, and myxozoans. [LUCA-the jelly team]

Coevolution - Reciprocal evolutionary changes in two or more interaction species. It may also happen in different level, such as subcellular up to ecosystems. [The Cotatwor Team]

Community - All actually or potentially interacting species present in a defined area at the same place and time. [Team ecoevo]

Conservation (biology) - The preservation of biological diversity, in all its levels (from genes to ecosystems, including ecological interactions). The long-term goal of ‘conservation biology’ is the persistence and viability of functioning ecosystems (Soulé 1985). To reach its goals, conservation biology can make use of different tools, approaches and disciplines, including genetics, ecology, geography, physiology, sociology, systematics, climatology, etc. [Sacrivzoa Team]

Convergence - All instances of the independent evolution of the same given phenotype, regardless of whether the taxa are closely or distantly related (*).
Historically convergence was used to specify repeated evolution of a phenotype in distantly related taxa (while parallelism historically referred to closely related organisms). Convergence has also been used to refer to independent evolution of phenotypic traits via different genetic pathways whereas parallelism referred to genetic changes in the same pathways.
(*) Arendt and Reznick (2009) concluded that the distiction between 'convergence' and 'parallelism' cannot be made since many examples on genetic approaches among related and unrelated taxa have shown that either different gene changes or the same gene chances can drive to simmilar phenotype states on both distant or close related clades! [Parallel mutucas]

Cryptic species - Two or more distinct species that are morphologically similar or even identical. In many cases, this species cannot be distinguished by external morphological traits but through molecular data, differences in mating behavioral, chemical signals, physiology, habitat preferences, etc. [Sacrivzoa Team]

D (Back to Top)

Developmental genetics - [Evo-Ego Team]

Developmental homology - Structures that arose from the same tissues during embryonal development. E.g. ovaries and testes.

Diversification - In biology, the multiplication of biodiversity, in general. [Team ecoevo]

Diversification rate - (1) A rate of diversification is a measurement of how the number of species in a lineage varies in an interval of time. In practice is the sum of speciation rates and extinction rates of that lineage in an interval of time [The Disturbed Team]. (2) Also the Rate of increase in biodiversity, for example, we can understand diversification by studying lineages through time and in this case diversification is measured by a proxy or index.[Team ecoevo]. (3) Rate of increase in terminals in a clade, that is driven by the processes of speciation and extinction. [The Gotham Project]

Durophagous animals - Animals which eat preys with hard exoskeleton and shells. [The Gotham Project]

E (Back to Top)

Ecological diversification - The evolution of divergent ecological characteristics within a lineage (Stephens and Wiens, 2003). [The Gotham Project]

Ecological interaction - Any relationship between two elements in an ecosystem. [Team ecoevo]

Ecological network - A set of interacting nodes (usually species) that are connected to one another edges. One example is food webs, in which links between species represent trophic interactions (Woodward et al., In press). [Team ecoevo]

Ecological niche modeling - Is a tool that allows predictions about species potential ranges based on environmental parameters, using computer algorithms (Soberón & Peternon, 2004). In ecological niche modeling, known occurrences of species (realized niche) are related to raster environmental data layers (e.g., salinity, depth, temperature) to reconstruct the potential distribution of species under those parameters, without considering biotic interactions, or geographic barriers, for instance. [Sacrivzoa Team]

Ecosystem - All actually or potentially interacting abiotic and biotic entities in a defined area, as well as their interactions. [Team ecoevo]

Edge - A connection between two nodes in a network. [Team ecoevo]

Embryology - the branch of biology and medicine that studies embryos and their development (Oxford dictionary). [Evo-Ego Team]

Entocodom n - (Gr. entos, within; kodon, bell) (CNIDARIA: Hydrozoa) The primordium of the subumbrella in the development of medusae from the gonophore. [LUCA-the Jelly team]

Evolutionary change - The change in a lineage of populations between generations (Decent with modification). [The Cotatwor Team]

Evolutionary development (evo-devo) – a field of biology that compares the developmental processes of different organisms to determine the ancestral relationship between them, and to discover how developmental processes evolved. It addresses the origin and evolution of embryonic development; how modifications of development and developmental processes lead to the production of novel features (Wikipedia) [Evo-Ego Team]

Evolutionary Diversification - An increase in genetic variation among populations within a particular species or species complex, including adaptive divergence of lineages as well as the special case of the formation of new hybrid lineages [The Disturbed Team].

Evolutionary dead-end - A lineage that is either 1) very likely to go extinct or 2) has its evolution highly constrained so it is not able to diversify. The first situation arises when a trait, which may be iniatially advantageous, has a deleterious effect in the long run (e.g., self-compatibility in plants). The second situation arises when the evolution of certain traits constrains further diversification of the group, so it is unable to explore different lifestyles (e.g., loss of the digestory system in parasite cestod tapeworms). [404 - Page not found]

Extinction - In a phylogenetic context, the termination of a branch in a phylogenetic tree; that is, a branch that has no living descendants and cannot therefore be reconstructed from data obtained from contemporary species (Ricklefs, 2007). [The Gotham Project]

Extinction rates - The number of evolutionary lineages that get extinct per unit of time. [the X-team]

Exumbrellar rim - The rim of the umbrella part of the jellyfish. [LUCA-The Jelly Team]

F (Back to Top)

Fitness - The success of an entity in reproducing; hence the average contribution of an allele or genotype to the next generation or to succeeding generation. [The Cotatwor Team]

Fossil - Any vestige of remains or of biological activities (e.g. trace fossils, coprolites, footprints) from an organism recorded in rocks and sediments. [The Gotham Project]

Frugivores - Organisms that have a diet based on fruits. [The Gotham Project]

Fundamental niche - The abiotic conditions in which a species is able to persist (Hutchinson, 1957). [Sacrivzoa Team]

G (Back to Top)

Gape width - The maximum width of an organisms mouth (buccal cavity), which defines the maximum size of a prey item that an organism can ingest. [Team ecoevo]

Gene expression - The process by wich information from a gene is used in the synthesis of a functional gene product

Gene flow - Is the transfer of alleles from one population to another. It may be responsible for a marked change in allele frequencies. Maintained gene flow between two populations can lead to a combination of the two gene pools, reducing the genetic variation between the two groups. [Sacrivzoa Team]

Gene expression - the process by which possession of a gene leads to the appearance in the phenotype of the corresponding character (Oxford Dictionary). [Evo-Ego Team]

Generalization - An intermediate phenotype is produced that is moderately successful in most environments (Dewitt and Langerhans, 2004). [The Gotham Project]

Genome - All the hereditary information of an organism, coded within its genetic material (DNA or RNA). Eukaryote genomes are usually made of DNA, bacterial genomes are circular. The genome of some virus is composed of RNA. [Evo-Ego Team]

Genomics - the branch of molecular biology concerned with the structure, function, statistical analysis, evolution, and mapping of genomes (Oxford Dictionary). [Evo-Ego Team]

Geographic mosaic - Natural selection on interspecific interactions varies among populations partly because there are geographic differences in how fitness in one species depends up on the distribution of the genotypes in another species. That is , often a genotype-by-genotype-by-environment interaction in fitness of interacting species. [The Cotatwor Team]

H (Back to Top)

Homology - Two or more structures are homogous if they share the same origin - shared ancestry - and thus a common developmental origin.
Homology does not necessarily imply similar function - e.g. leaves and spines on higher plants.

Homoplasy - A trait that is shared by two or more taxa, but not by a common ancestor. These evolved independently in different lineages.
Example: homeothermy on mammals and birds. [Parallel mutucas]

Hydroids - are colonies of tiny stinging jellies. [LUCA-the Jelly team]

Hydrozoans - They are a taxonomic class composed by very small animals that has predatory habits. They can live single or in colonies, mostly in saltwater, with few genera within this class living in freshwater. Hydrozoans are in the phylum Cnidaria . [LUCA-The Jelly Team]

I (Back to Top)

Insectivores - It is a type of carnivore which has a diet essentially based on insects. [The Gotham Project]

Interaction strength - The impact of one population (of one species) on the distribution, abundance, and/or body size of another population (species) important in the same community. Alternatively, this can be defined as the amount of flows of energy and matter interchanged between two or more elements within an ecosystem. [Team ecoevo]

K (Back to Top)

Key innovation - Changes in phenotypic aspects of organisms (e.g. morphological, physiological, behavioral or molecular) that may enhance competitive ability, relax adaptive trade-offs, or permit exploitation of a new productive resource base. This enhance makes a taxon more or less committed to a way of life different from, or appreciably more efficient than, that of its ancestors and is essential to the origin of new major groups, which could increasing diversification rate in the resulting clade [404 page not found]

L (Back to Top)

Latitudinal Gradient of Diversity (LGD) - It is the pattern of species diversity across the latittudinal gradient. It is known that extant species are more diverse at lower latitudes than at higher latitudes. The LGD has been observed to varying degrees in Earth's past. [Cotatwor team]

Life cycle - a set of transformations by which organisms of a particular species pass through their lives. The cycle is divided into developments stages or phases that can be named according to the organism that is the target of the study. [LUCA-the Jelly team]

M (Back to Top)

Manubrium - A structure found in jellyfish that hangs from the center of the bell and contains the mouth (Encyclopedia Britanica). [LUCA-The Jelly Team]

Marginal canal - A canal found on the margin of the bell of the jellyfish. [LUCA-The Jelly Team]

Mass Extinction - When the Earth losses more than 3/4 of its species in a geological short interval (Barnosky et al 2011). [the X-Team]

Medusae - Medusae are bell-, dish-, or umbrella-shaped cnidarians, and usually embedded with a thick, jelly-like mesogleal layer (hence the name jellyfish). The free medusa stage occurs in all cnidarian classes except the Anthozoa. [LUCA-the jelly team]

Mimicry - When different species exhibit convergent phenotypes that protects one or both of the species. Example: butterflies species share colour patterns in order to share the cost of warning predators as to their bad taste. [Parallel Mutucas Team]

Modern synthesis - a union of ideas from genetics,systematics, morphology, ecology and paleontology produced between 1936 and 1947 that provided a widely accepted account of evolution, giving a common ground for changes ocurring at large tmeporal scales (macroevolution) with those studied at the population level (microevolution). Evoltionary development (evo-devo) was essentially not included in this integrative view (Wikipedia with modifications). [Evo-Ego Team]

Molecular Clock - Based on the theory of neutral selection, molecular clocks were proposed as a method to estimate the divergence time between different taxa. The theory assumes that DNA sequences mutate at an approximately constant rate. That way, the difference between the sequences found in two species is proportional to the time of divergence from a common ancestor [The Disturbed Team].

Monophyletic group - A group consisting of a single common ancestor and all of the descendants of that common ancestor. [The Gotham Project]

Morphological change - A change in a morphological trait may be driven by an adaptation to a given environment, be the result of ontogenetic development of an organism, or even reflect common ancestry, if the same (homologous) trait is changing along evolutionary history of a lineage.

Morphospecies - A species distinguished from others by its morphology. [Sacrivzoa Team]

Mutalism - An ecological interaction in which all involved species benefit from the interaction (e.g. in terms of increases in fitness or population growth rates).

Mutation - Process producing a gene or chromosome different from the wild type. Such changes may alter the structure or regulation of proteins transcribed, which can in turn influence positively or negatively the chance of survival and reproduction of organisms that have it in a given environment, in comparison to other members of the same species. Much mutations are neutral, having low or no impact on organism performance. [Evo-Ego Team]

N (Back to Top)

Nectivores - Animals that eat nectar. [The Gotham Project]

Network - model for the relationships between the elements in a system defined by nodes and edges. [Team ecoevo]

Niche - Is a hipervolumen of n dimensions in which a species is able to persist and maintain stable population sizes (Hutchinson, 1957). [Sacrivzoa Team][edited by 404 page not found]

Niche conservatism - The tendency of species to retain aspects of their fundamental niche over time (Wiens & Graham, 2005). [Sacrivzoa Team]

Niche width - Hutchinson’s (1957) conceptualized niche as an n-dimensional hypervolume, in which every point corresponds to a state of the environment that would allow a species to exist indefinitely (Pulliam, 2000). The fundamental niche is the species niche in the absence of biotic interactions (competition, predation) or other extrinsic agents (barriers to dispersal), while the realized niche is narrower because it considers species interaction and extrinsic agents (Roughgarden, 1974). The niche width corresponds to the variety of resources a population exploits (Roughgarden, 1972). [The Gotham Project]

Node - (1) In phylogenies - A node in a phylogeny represents a taxon or a common ancestor for a set of taxa. Nodes are also referred to as vertices. The degree of a node is the number of edges that are connected to it [The Disturbed Team]. (2) An individual element within a network (see also Ecological networks). [Team ecoevo]

O (Back to Top)

Omnivores - Organisms which eat both animals and plants. [The Gotham Project]

Ontogeny - is the origin and the development of an organism. [LUCA-the Jelly team]

P (Back to Top)

Parallelism - No longer a valid term as it is a synonym of "convergence" [Parallel-mutucas].

Parapatry - The biogeographical pattern in which two population ranges significantly overlap but are immediately adjacent to each other; they only occur together in the narrow contact zone, if at all. [Sacrivzoa Team]

Parasitism - A kind of a association in which the benefit is unilateral. One organism (parasite) benefits at the expense of another (host). [The Cotatwor Team]

Peripatry - The biogeographical pattern in which two populations ranges are closely adjacent but do not overlap, being separated by an area where these organisms do not occur. [Sacrivzoa Team]

Phenotype - The composite of an organism's observable characteristics or traits: such as its morphology, development, biochemical or physiological properties, phenology, behavior, and products of behavior (such as a bird's nest). Phenotypes result from the expression of an organism's genes as well as the influence of environmental factors and the interactions between the two [Parallel Mutucas Team].

Phyogenetic clustering- Is when a community is componed by species that are closely related than expected for chance [404 page not found]

Phylogenetic overdispersion-Is when a community is componed by species that are more phylogenetically distant than expected for chance[404 page not found]

Phylogeny - A phylogeny is a hypothesis of relationships among a group of organisms. Each extant taxa is represented by one terminal and the nodes represent ancestral events of speciation/cladogenesis. The relationships of extant taxa is inferred based on shared evolutionary novelties.

Phylogeography - The field of study concerned with the geographical distributions of genetic lineages within and among closely related species, studied to understand the processes driving population divergence and the impact of geographical phenomena on microevolution. [Team ecoevo]

Planulae - one of the larval stages in the development of coel-enterates. [LUCA-the Jelly team]

Pluripotent - cells that can originate most cells, but not all cells.

Poeciliidae - A family of small-bodied (pygmy) Neotropical freshwater fishes within the Percomorpha that possess unique reproductive and physiological adaptations for internal fertilization and sperm storage, and produce small precocious (capable of providing for themselves) offspring that are free-swimming at birth. [Team ecoevo]

Population - a set of individuals of the same species living in a defined area. [Team ecoevo]

Polyp - Polyps are tubular structures with an outer epidermis, an inner gut sac (coelenteron) lined with gastrodermis, and a layer of jelly-like mesoglea or mesenchyme in between. The polypoid stage occurs in all four classes of cnidarians. Polyps are very diverse, largely as a result of their capacities for asexual reproduction and colony formation. [LUCA-the jelly team]

Predation - An ecological interaction between two organisms whereby one organism consumes all or part of the other, so that it benefits at a cost to the other organism. [Team ecoevo]

Primary homology - A belief that different characters share an ancestry - but has not been tested yet. [Parallel Mutucas Team]

Protein Coding region - [Evo-Ego Team]

R (Back to Top)

Range size - The area, range, or geographic distrubution of a species [the X-Team]

Rate of evolution - Formalized in molecular evolution as the number of DNA substitutions (mutations) per site per unit of time (e.g. years, millions of years). [Team ecoevo]

Realized niche - The conditions in which a species persists given the presence of other species (e.g., competitors and predators) (Hutchinson, 1957). [Sacrivzoa Team]

Regeneration - the process by which something that lost is able to be restored. [LUCA-The Jelly Team]

Regulatory element - A DNA sequence that controls the activity of other genes or metabolic pathways.

Rejuvenation - the process by which aging is reversed. [LUCA-The Jelly Team]

Reverse Development - During life cycle, one or more stages in can reactivate genetic programs specific to earlier stages, leading to back-transformation and morph rejuvenation. (Hangbao et al, 2012). [LUCA-The Jelly Team]

S (Back to Top)


by dlahrdlahr 15 Aug 2012 22:58

[[size 110%]] This glossary is generated automatically.

Sanguinivorous - This term is related to blood sucking animals. [The Gotham Project]

Secondary homology - The homology turns into "secondary" state when the primary homolgy passas through a parsimony analysis and seem to have appeared only once on a tree - and thus seem to be homologous. [Parallel Mutucas Team]

Selection - Trait states are determined by genetic background and vary along individuals within a population. Environmental changes pose a pressure on natural populations. Individuals that have certain traits and trait states manage to survive and reproduce more efficiently than other individuals in the population. Through this process, organisms of a population that are better adapted to their environment tend to increase the relative frequency of their genes in relation to less able to organisms over a number of generations. [Evo-Ego Team]

Selective pressure - Any phenomena which alters the fitness of an organism. There are two main divisions in that kind of pressure: biotic and abiotic. [The Cotatwor Team]

Sex - The change in ploidy that results from the alternation between meiosis and syngamy in the life cycle of a eukaryotic species. Usually genetic recombination is involved during meiosis. [Sacrivzoa Team]

Signaling network - A system of proteins and other biomolecules implicated in the transduction of stimuli to the machinery involved in the regulation of gene expression and protein levels. [LUCA-the Jelly team]

Specialization - An optimal phenotype is produced for a given environment, even though the specialist might find itself sometimes in alternative environments (Dewitt and Langerhans, 2004). [The Gotham Project]

Speciation - In a phylogenetic context, the splitting of an ancestral lineage into two evolutionarily independent descendant lineages (Ricklefs, 2007). [The Gotham Project]

Speciation rate - A rate of speciation is a measurement of how many new species appear in an interval of time within a given taxon and a given habitat, region, or ecosystem. A rate of speciation can also be a comparative measure, less dependent on time, relating to how one taxon seems to diversify relative to another [The Disturbed Team].

Stem Cells - Are self-renewing cells which are characterized for maintaining pluripotency. These properties allow them to go through several cycles of cell division maintaining their undifferentiated state and the capacity to differentiate into any specialized cell type (Toledo et al, 2008). [LUCA-The Jelly Team]

Synapomorphy - A trait that is shared by two or more taxa and a common ancestor, a shared derived character. [Parallel mutucas]

Sympatry - The biogeographical pattern in which two populations coexists in the same area. [Sacrivzoa Team]

Symplesiomorphy - A trait that does not to circumscribe a monophyletic group. Instead it is shared by two or more taxa, but also by other taxa that don't share a common ancestor.
Trophic Level - The hierarchical position of energy acquisition in organisms which ranges from primary production (eg. plants, bacteria) to top predators (eg. sharks, lions) and decomposers (eg. fungus) [the X-team]

Symbiosis - An intimate, usually physical, association between two or more species. [The Cotatwor Team]

Systematics - the branch of biology that deals with classification and nomenclature, i.e., taxonomy. It also includes the study of the evolutionary relationships among species (Oxford Dictionary).[Evo-Ego Team]

T (Back to Top)

Transcription factor - A protein that binds to a specific DNA sequence and regulates the transcription of genetic information from DNA to RNA.[LUCA-the Jelly team]

Transcriptome - is the set of all RNA molecules.

Transdiferentiation - Is a non-stem cell transforming into a different type of cell, or a differentiated stem cell changing to another type of cells. (Piranio et al, 2004). [LUCA-The JellyTeam]

U (Back to Top)

Ultimate convergence -It would be used to reffer to convergencies observed among very distant representants from the Tree of Life, which may have evolved from not homologous developmental networks, assuming that the traits evolved independently (Leander, 2008). [Parallel Mutucas]

Ultrametric tree - An ultrametric tree is a rooted tree with edge lengths where all branches are equidistant from the root. Branch lengths often represent of time divergence [The Disturbed Team].

Reproductive isolation - The condition in which two organisms are not capable of maintaining genetic exchange. There are two main mechanisms of reproductive isolation: pre-zygotic and post-zygotic. Reproductive isolation is, under the biological species concept, sin qua non of good species (Orr 2005) and it typically evolves in allopatry (Coyne and Orr 2004; Mayr 1963), but there are exceptions to this pattern. [Sacrivzoa Team]

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License