Morphometrics (or morphometry)1 refers to the study of shape variation of organs and organisms and its covariation with other variables : “
Scientific production in the morphometric field has increased dramatically over the last few decades. I do not doubt that largely this has resulted from easily available and (usually) fairly comprehensive computer programs, cheaper and more powerful personal computers, and more specialized and less expensive equipment for raw data acquisition: “
Therefore, in addition to the “classical” tools for obtaining data (such as images), there is currently a wide spectrum of very advanced technology available, making measurements of any type easier, with more resolution, three‐dimensional, less invasive and more complex: computed tomography, magnetic resonance imaging, ultrasound, surface scanners and other three‐dimensional data‐collection devices, scanners.2 An example of this “new technological age” is the estimation of body surface area (BSA). The estimation of BSA can be traced back to 1793, when Abernathy directly measured the surface area of the head, hand, and foot in humans using triangular‐shaped paper, estimating the remaining segments of the body using linear geometry . Similarly in animals, initial BSA data were obtained by pasting strips of strong manila paper, gummed on one side, to the hair of the animals  or rolling a revolving metal cylinder of a known area, attached to a revolution counter . Recently, however, complex techniques, such as computed tomography have been applied , and these have undoubtedly improved the quality (precision, ease) of data (and, frankly, I cannot imagine a live ferret being wrapped in a sheet of paper to estimate its BSA!).
A personal comment is in order here. These considerations have not been developed according to any deeper theoretical considerations. They are mainly based on personal experience of working with morphology in different contexts. Their aim is to provide an intuitive overview of how and for what purpose morphology can be applied, rather than attempting to formulate a strict thesis. Perhaps, needless to say, this is a text aimed at presenting certain personal ideas about morphometrics and morphology, not an attempt to give an exhaustive presentation of the literature on the topic. The bibliography presented is simply for things to make more sense and to demonstrate how I justify some assumptions on conceiving the ideas set forth.
Let us continue. Current software for morphometry can analyze data whatever their origin, and normally, it allows the construction of relevant images (the role of visual representations is very important in morphometrics, although algorithms sometimes cannot show completely accurate results, for instance, because they are not well adapted to a discrete framework).
Morphometrics was initially performed on organisms (
With this availability of many computational facilitations and so wide a spectrum of applications, current morphometric research cannot simply be applied to such a wide range of fields, but also requires the combination of many disciplines. All of these factors add up to a complex task, which should not be beyond our power as ordinary scientists. Morphometrics increasingly calls for an integrative research approach, in addition to a good understanding of the mathematical or logical basis of the approach considered.
In summary, we can give many answers based on any motivation of measurement, not only form, the
In conclusion, morphometrics, being a branch of statistics, must be viewed as a branch of morphology in the widest sense.6 Also, on emphasizing the broad component of morphology, we do not rule out the significance of its mathematical component.
- From the Greek μορϕή, morphe, meaning “form”, and –μετρία, metria, meaning “measurement.” The term “morphometrics” seems to have been coined in 1957 by Robert E. Blackith from Dublin University, who studied the subject in relation to locusts .
- No single type of imaging is always better; each has different potential advantages and disadvantages, and obviously their interpretation is subject to the hypothesis at hand.
- Shape contains the whole geometry (i.e., proportions) of objects, but it does not always take into account the overall complexity of the geometry of the specimens .
- From the Ancient Greek don, morphé, meaning “form,” and λόγος, lógos, meaning “word, study, research”.
- From the Ancient Greek ἀνατομή, anatomē, meaning “dissection”, and –τέμνω, témnō, meaning “I cut”.
- And with morphometric technique being dependent on images, would it be better defined as “morphography”? I leave it to the readers’ consideration.