Formal and scientific classifications of Cladistics in manufacturing

Published: Last Edited:

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Cladistics in Manufacturing:

McCarthy (1995) discussed the importance of formal and scientific classifications for understanding the diversity of manufacturing organizations and their defining characteristics (technological, social, operational and structural). Cormack (1971), in his lecture to the Royal Statistical Society, summarised the benefits of a hierarchical classification, stating that: the information about the entities is represented in such a way that it will suggest fruitful hypotheses which cannot be true or false, probable or improbable, only profitable or unprofitable. Supporting the need for an organizational classification is Romanelli (1991), who states: despite the ease with which we may identify meaningful groupings of organisations, no commonly accepted classification scheme has been developed.

There are two main principles of classification within the biological sciences: the phenetic and the phylogenetic principles. From these two underlying principles emerge three approaches to classification, or schools of classification: phenetic; evolutionary; and cladistic. The three schools of classification are differentiated on the basis of how closely they adhere to a purely phylogenetic (evolutionary ``tree of life'') principle. Cladistics is a purist approach to the phylogenetic principle. Phenetic classifications are nonevolutionary, they differentiate purely on the physical appearance and behaviour of the entity, and are thus at the opposite end of the evolutionary focus scale. Evolutionary classifications are a synthesis of the phenetic and phylogenetic principles. Phylogenetic classifications have become known as cladistic classifications, because the phylogenetic principle was defended by the German entomologist Willi Hennig (Ridley, 1993), and supporters of his ideas called the principle phylogenetic systematics, which has now evolved into the term, cladism. The cladistic school of classification involves studying the evolutionary relationships between entities with reference to the common ancestry of the group. Constructing a classification using evolutionary relationships is considered beneficial, because the classification will be unique and unambiguous. In the words of Ridley (1993, p. 367): Cladism is theoretically the best justified system of classification. It has a deep philosophic justification which phenetic and evolutionary classifications lack.

Wiley et al. (1991) and De Queiroz (1988) assess the three schools of cladistics on their ability to produce natural and objective classifications, rather than artificial and subjective classifications. Cladistics is the only one out of the three that satisfies both these criteria, as the entities within a cladistic classification will resemble each other in terms of the defining characteristics and the non-defining characteristics (characteristics not used to represent the phylogenetic relationships). Cladistics conforms to the criteria of objectivity because it represents a real unambiguous and natural property of the entity (evolutionary relationships) and thus different rational people, working independently, should be able to agree on a classification.

If the need for change stems from chaotic markets then it is likely, almost common sense, that manufacturing organizations should be treated as complex evolving systems. Like nature, manufacturing companies and the industries within which they exist have evolutionary dynamics, which tend to result in irreversible events whereby new ways of working and technology supersede redundant processes. Manufacturing companies are organizational systems and, as such, conform to the thinking and knowledge on how organizational systems exist and evolve. To apply evolutionary models outside biology, you need to know what evolution is in the context of the entities under study (manufacturing organizations) and the domain in which they exist (industrial and economic ecosystem). A cladogram is a tree structure which represents the evolutionary history of a group of manufacturing organizations. The tree structure illustrates the diversity of manufacturing forms, the relationships between the different forms and the evolutionary paths between each of the forms. These evolutionary paths represent the organizational change programmes which must be undertaken to move from one form to another. Each path on the cladogram is formed according to the acquisition and polarity of certain characters (manufacturing characteristics).

A cladogram clearly shows the difference between morphogenic change and morphostatic change. Each of the branching points on the cladogram is an organizational speciation event (morphogenic change) and in cladistic terms this is known as cladogenesis. The manufacturing characteristic which immediately precedes the branching point initiates this morphogenic change, whilst the characteristics which follow this first characteristic on the branch are producing refinements of this new manufacturing form. The acquisition of these characteristics is known within cladistics as anagenesis and is equivalent to morphostatic change.

Using a systematic and comparative method such as cladistics, permits an assessment of the generality of the attributes of complex systems (Pinna, 1991). Cladistic classifications and the desire to develop a theory of organizational differences could play a significant role in explaining the processes by which the practices and structures of organizations and organizational forms persist and exist over time. A cladogram provides a snapshot of the evolutionary history of a company. Thus, it can be used by managers to check that their vision for the future is consistent with their understanding of the past. Cladistics also provides an interesting measure of strategic excellence, through the principle of parsimony. A cladistic classification of manufacturing organizations could provide a system for conducting, documenting and coordinating comparative studies of manufacturing organizations. Such a system could provide the consensus for formally approving, validating and typifying the emergence of new manufacturing forms. Cladograms would represent the contours of change for a manufacturing industry, thus providing knowledge and observations on the patterns of the distributed characteristics exhibited by manufacturing organizations over their evolutionary development.

If a classification is linked to this change process, it is postulated that groups of manufacturing systems can be formed based on similar technological and behavioural attributes, and that there will exist an “ideal model” or solution for the group. This group reference model will then help reduce the time and costs associated with developing solutions for individual companies within that group. A second objective for producing a manufacturing classification is based on the process of comparative study which enables the storage and retrieval of information to facilitate the application of generalizations points. This process enhances the investigators' knowledge and understanding of manufacturing systems and will enable predictions about system behaviour.

Product changes have often triggered a change or a series of changes in its manufacturing system. It can also be envisioned that a newly installed manufacturing system or machines, would encourage product changes to utilize most of the extended system capabilities. Since adding, removing, or changing manufacturing system's modules changes its capabilities and functionality, the system would be capable of producing new product features that did not exist in the original products family (Wiendahl et al 2007). This allows the system to respond to the rapid changes in products, their widening scope and faster pace of customization. This observed symbiotic relationship between products and their manufacturing systems provides the motivation for studying the change mechanism(s) on both sides and investigating their boundaries, inputs and outputs.

On the system level, the term ‘Evolution' was used to mean the manner in which a certain industry or organization historically and chronologically transformed through time. For example, the factors that influenced developments in industry and manufacturing in Canada in the last three centuries were explained by Balakrishnan et al (2007).

A more recent example of the use of cladistics within the manufacturing environment was given by ElMaraghy et al (2008), where they utilised the techniques of cladistics when carrying out an analysis of an engine cylinder block manufacturer. They used this case study as an example to demonstrate the proposed cladistic analysis workings and merits. The cylinder block variants belonged to automotive engines of different makes, material and types from Japan and North America, ranging in capacity from half a litre to six litres. The cylinder blocks are made of either aluminium or cast iron. They belong to either inline or V-type, highdeck or low-deck, front or rear wheel drive, over head cam (OHC) or over head valve (OHV) engines (ElMaraghy et al 2008). The resulting cladogram was used to classify the evolution of the engine cylinder blocks, as it embodied knowledge extracted from analysis to provide a valuable insight into both past and present manufacturing trends. Cladistics was also used to improve the current product variants families by determining the best family of products to which a new variant would best belong.

Building on their previous work carried out in 2008, AlGeddawy and ElMaraghy (2009) proposed an assembly systems layout design model for delayed product differentiation which was also based on cladistics. The main focus of their research was the design and synthesis of assembly systems layouts for implementing delayed products differentiation for a family of product variants. The case study carried out consisted of a family of five household products, with all members of the product family being heating appliances for water or food that share some common as well as distinctive features. Because of the similarities and differences these products were considered as candidates for being produced on a DPD assembly line. The information collected from the cladistical analysis facilitated the generation of the precedence charts of the family of the five products. The precedence chart of a product is represented by a set of nodes and arrows, where each node consists of a component or a module that will be assembled to form that product, and arrows show the flow of the assembly steps, hence, each assembly precedence chart lays out the assembly map according to which the product components and modules are brought together, and its nodes and arcs represent the required assembly processes (AlGeddawy and ElMaraghy 2009).

The present manufacturing environment puts a tremendous amount of pressure on manufactures to offer a wide range of product variants  to satisfy widening customer demands, whilst still maintaining a competitive pricing and logistical system. However in offering a widened product range manufacturers commit themselves to an expansion in the number of sub assembly processes as well as an increase in the level of raw materials which they need to stock in order to satisfy the increased product variation. Building on their work carried out in 2009 on delayed product differentiation, AlGedday and ElMaraghy employed the tools of cladistics in order to develop a model of a single assembly line which was applied to a group of automible engine accessories which are normally assembled on different lines. Cladistics was used in planning the DPD assembly line configuration so as to incorporate the assembly precedence constraints, the required production rates of product variants and the existing production capacity of the work stations (AlGedday and ElMaraghy 2011). A group of five varying engine accessories were considered as part of the study with each normally produced using different assembly lines. Cladistics was used to determine the shortest possible evolutionary tree for the varying assembly lines based on a commonality analysis of components and assembly processes as well as to explore the possibility of unifying all the various assembly lines under a single assembly system. The end result of using cladistics to facilitate the design of this assembly system was an optimum balanced assembly line layout for the delayed product differentiation of automotive engine accessories.