A system of hierarchical classification that proceeds by subdividing the whole into successively smaller and more homogeneous units.
In taxonomy, a new, replacement name, published as a substitute for an invalid one (e.g. a junior synonym).
In taxonomy, a name that must be rejected under the rules of the Code and is therefore illegitimate.
The whole-arm fusion of chromosomes by the joining together of two acentric chromosomes to form one metacentric chromosome.
(pears; family Rosaceae)A genus of deciduous, sometimes thorny trees and shrubs, that have simple leaves and flowers borne in umbel-like clusters. There are 5 sepals, 5 petals, 20–30 purple stamens, ...
In taxonomy, a name that has not been published properly, or is unavailable, and which is therefore invalid.
The acquisition of patterns of behaviour by repeating similar behaviour observed in others, not necessarily of the same species.
Describing organisms that feed by ingesting complex organic matter, which is subsequently digested and absorbed. See heterotrophic nutrition; ingestion.
The successive species in a phyletic lineage that are given ancestor and descendant status according to the geological strata in which they appear. See anagenesis.
; phylum Cnidaria, class Anthozoa)An order of colonial, branching corals in which the polyps are small, with few tentacles (six simple, or eight branched) and few unpaired mesenteries (6, 10, or 12). ...
Capable of digesting pectin, the material that acts as a kind of cement between the cells of higher plants.
(family Fabaceae, subfamily Caesalpinoideae)A genus of big trees which have pinnate leaves. There are 4 sepals, 1 petal, 9 fused stamens, and 1 free stamen. The fruit is a flat, rounded, woody, ...
Any cell (nucleus) not undergoing division. The cell (nucleus) is nevertheless very active metabolically. See cell cycle.
An egg in which the yolk occurs at one end of the cytoplasm, giving rise to a vegetal pole. Mesolecithal and macrolecithal eggs are also telolecithal. Compare isolecithal.
The female gamete contained within an oogonium. Fertilization of an oosphere is followed by the development of an oospore.
The situation in which two species populations coexist, with neither population being affected by its association with the other.
In taxonomy, a name that was published at some time in the past, but has subsequently been overlooked.
The artificial synthesis of double strands of polynucleotide molecules by binding together complementary strands of RNA and/or DNA. Such techniques permit the estimation of genetic similarity between ...
The last segment of the foot in an insect. It has a pad with a claw on either side.
; order Marsupialia (or Diprotodontia), superfamily Phalangeroidea)A family of mainly arboreal, herbivorous marsupials in which the hallux is well developed and often opposable and the tail is long ...