Morphology is a branch of

biology Biology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditar ...

dealing with the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance ( shape,

structure A structure is an arrangement and organization of interrelated elements in a material object or system, or the object or system so organized. Material structures include man-made objects such as buildings and machines and natural objects such as ...

, colour, pattern,

size Size in general is the Magnitude (mathematics), magnitude or dimensions of a thing. More specifically, ''geometrical size'' (or ''spatial size'') can refer to linear dimensions (length, width, height, diameter, perimeter), area, or volume ...

), i.e. external morphology (or eidonomy), as well as the form and structure of the internal parts like bones and organs, i.e. internal morphology (or anatomy). This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of gross structure of an organism or taxon and its component parts.

History

The

etymology Etymology () The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the form of words ...

of the word "morphology" is from the

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic p ...

(), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Friedrich Burdach (1800). Among other important theorists of morphology are Lorenz Oken,

Georges Cuvier Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French natural history, naturalist and zoology, zoologist, sometimes referred to as the "founding father of paleontology". Cuvier ...

, Étienne Geoffroy Saint-Hilaire,

Richard Owen Sir Richard Owen (20 July 1804 – 18 December 1892) was an English biologist, comparative anatomist and paleontologist. Owen is generally considered to have been an outstanding naturalist with a remarkable gift for interpreting fossils. Owe ...

, Karl Gegenbaur and

Ernst Haeckel Ernst Heinrich Philipp August Haeckel (; 16 February 1834 – 9 August 1919) was a German zoologist, naturalist, eugenicist, philosopher, physician, professor, marine biologist and artist. He discovered, described and named thousands of new sp ...

. In 1830, Cuvier and E.G.Saint-Hilaire engaged in a famous debate, which is said to exemplify the two major deviations in biological thinking at the time – whether animal structure was due to function or evolution.

Divisions of morphology

* Comparative morphology is analysis of the patterns of the locus of structures within the body plan of an organism, and forms the basis of taxonomical categorization. * Functional morphology is the study of the relationship between the structure and function of morphological features. * Experimental morphology is the study of the effects of external factors upon the morphology of organisms under experimental conditions, such as the effect of genetic mutation. * Anatomy is a "branch of morphology that deals with the structure of organisms". * Molecular morphology is a rarely used term, usually referring to the superstructure of polymers such as fiber formation or to larger composite assemblies. The term is commonly not applied to the spatial structure of individual

molecules A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioche ...

. * Gross morphology refers to the collective structures of an organism as a whole as a general description of the form and structure of an organism, taking into account all of its structures without specifying an individual structure.

Morphology and classification

Most taxa differ morphologically from other taxa. Typically, closely related taxa differ much less than more distantly related ones, but there are exceptions to this. Cryptic species are

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

which look very similar, or perhaps even outwardly identical, but are reproductively isolated. Conversely, sometimes unrelated taxa acquire a similar appearance as a result of convergent evolution or even

mimicry In evolutionary biology, mimicry is an evolved resemblance between an organism and another object, often an organism of another species. Mimicry may evolve between different species, or between individuals of the same species. Often, mimicry f ...

. In addition, there can be morphological differences within a species, such as in '' Apoica flavissima'' where queens are significantly smaller than workers. A further problem with relying on morphological data is that what may appear, morphologically speaking, to be two distinct species, may in fact be shown by

DNA analysis Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or ...

to be a single species. The significance of these differences can be examined through the use of

allometric engineering Allometric engineering is the process of experimentally shifting the scaling relationships, for body size or shape, in a population of organisms. More specifically, the process of experimentally breaking the tight covariance evident among componen ...

in which one or both species are manipulated to phenocopy the other species. A step relevant to the evaluation of morphology between traits/features within species, includes an assessment of the terms: homology an
homoplasy
Homology between features indicate that those features have been derived from a common ancestor. Alternatively, homoplasy between features describes those that can resemble each other, but derive independently via parallel or convergent evolution.

3D cell morphology: classification

Invention and development of microscopy enable the observation of 3-D cell morphology with both high spatial and temporal resolution. The dynamic processes of these cell morphology which are controlled by a complex system play an important role in varied important biological process, such as immune and invasive responses.

References

External links