About Us: Taxonomic Concepts and Methods

We believe that phylogenetic discontinuity is obvious for most groups approximating the family level and higher categories. Therefore, baraminology sees multidimensional biological character space crisscrossed with a network of discontinuities that circumscribe islands of biological diversity. Within these character space islands, the basic morpho-molecular forms are continuous or potentially continuous. Discontinuity in this sense does not refer to either the minor breaks in quantitative ranges that are used to delimit species or the modifications on a basic theme that demarcate genera. It is the unbridged chasms between body plans - forms for which there is no empirical evidence that the character-state transformations ever occurred. The mere assumption that the transformation had to occur because cladistic analysis places it at a hypothetical ancestral node does not constitute empirical evidence.

The baramin concept, as recently refined (Wood et al, 2003), includes all the organisms in a single bounded region of biological character space. This concept is a theoretical construct intentionally left fluid, as it is unlikely all members (all past ancestors and present descendants) can actually be known. However, four other terms (with baramin as a root) are used to apply the concept to sets of known organisms:

• A holobaramin is the complete set of known organisms that belong to a single baramin. In other words, it is a group that (1) shares continuity (meaning that each member is continuous with at least on other member) and (2) is bounded by discontinuity. This is the empirical approximation of the theoretical baramin.
• A monobaramin is a group of known species that share continuity without regard to discontinuity with other organisms. That is, it may be either part or all of a holobaramin.
• An apobaramin is a group of known species that are bounded by discontinuity without regard to internal continuity. That is, it may be one or more complete holobaramins.
• A polybaramin is an artificial group of known species that share continuity with organisms outside the group and discontinuity occurs within the group. That is, it consists (through faulty analysis) parts of two or more holobaramins and should be avoided, as it is comparable to a polyphyletic taxon in conventional systematics.

These groups are not taxonomic ranks but approximations of the "created kinds" or "created biodiversity units". From the definitions, it is clear that a given conventional taxon may be thought of as a monobaramin, a holobaramin, or an apobaramin, depending on the available data supporting either continuity or discontinuity among its members. For example, if diverse species can hybridize (at least in the laboratory), they exhibit continuity and they are members of the same monobaramin. On the other hand, mammals, which are characterized by a unique yet varied body plan, are probably discontinuous from other vertebrates and comprise an apobaramin. If data exist that support both internal continuity and a boundary of discontinuity, the taxon would be a holobaramin. Thus, as more information becomes available, a monobaramin may become a holobaramin or an apobaramin may become a holobaramin.

Thus, the method of baraminology is successive approximation. Baraminology provides the framework for membership criteria through its emphasis on additive and subtractive evidence (see below). Additive evidence is used to establish that two species are truly related (members of the same monobaramin). Subtractive evidence is used to show that two groups of species are not related (different apobaramins). By building up a monobaramin by additive evidence and dividing out unrelated species from the larger apobaramin, the holobaramin should be converged on when the membership of the growing monobaramin and shrinking apobaramin are the same. See Wood and Murray 2003.

Major Additive Criteria:

1. Succesful interspecific hybridization. If members of two different species can successfully hybridize, they share genetic and morphogenetic programs and are, thus, holistically continuous. Although Marsh (see historical context) relied on hybridization as the single method of identifying which species were members of the same baramin, the problems with using hybridization as the exclusive baraminic membership criterion are many. Asexually reproducing species and species known only from fossils are impossible to classify using hybridization. Even among sexual species, failure to hybridize may be due to other causes than discontinuity.
2. Morpho-molecular similarity. Are the natural and artificially hybridized forms linked by overlapping quantitative measures, by character-state transitions in which all the states are observable in known and otherwise similar organisms, or by a homoplastic distribution (recombination) of redundant character states among similar organism? A statistical measure has been developed called Baraminic Distance (BD). A positive correlation of BD is interpreted as evidence of continuity of two organisms.
3. Stratomorphic Series. Stratigraphic fossil series connected by clear character-state transitions are evidence of continuity. For example, fossil and modern equids qualify as a monobaramin (see Cavanaugh et al. 2003).

Major Subtractive Criteria:

1. Scripture claims discontinuity. This should be concluded only after completion of a semantic and contextual study of relevant words and passages. Clear examples are that Scripture claims humans to be an apobaramin and that cetaceans are discontinuous from land mammals (i.e., each created on separate days).
2. Morpho-molecular dissimilarity. Are the natural and hybridized forms within the group separated from organisms outside the group by gaps that are significantly greater than intra-group differences? A negative correlation of BD is evidence of discontinuity.
3. Unique synapomorphies. Is the group circumscribed by a set of unique morphologies or molecular sequences? These synapomorphies should lack empirically observed transitions to states in other supposedly related but outside groups.
4. Lack of fossil intermediates. That is, there is no known fossil ancestral group, and fossils with "ancestral states" or "states transitional to other groups" are unknown. Forms identifiable in Flood sediments were probably distinct from the time of creation. A good example is Archaeopteryx, which likely represents its own unique baramin, distinct from both dinosaurs and modern birds.