Created kind
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In creation biology, created kinds are believed to be the original forms of life as they were created by God. They are also referred to as "kinds," "original kinds," "Genesis kinds," and "baramin" (from the Hebrew words "bara" [created] and "min" [kind]; the combination does not work syntactically in actual Hebrew). The idea is promulgated by Young Earth Creationists to support their view of Creation according to Genesis and also that the descendants of all land-based life on Earth were housed on Noah's ark before the great flood.
In contrast to the scientific principle of common ancestry, these creationists argue that all life on Earth is not related, but that life was created by God in a finite number of discrete forms. Those making more sophisticated arguments often acknowledge that these discrete forms subsequently underwent speciation and microevolution of the original created kinds. However, creationists assert that the created kinds constitute definite boundaries beyond which evolutionary processes cannot occur.
Since created kinds refer to common ancestry, they are asserted to be a form of clade. Baraminology, or the effort to classify life according to the created kinds, is thus the creationist equivalent of cladistics.
Mainstream scientists reject the idealization of "created kinds" and creation science in general as a pseudoscience. This is mainly because the scientific evidence for common ancestry and the relationships of lifeforms in the biosphere corresponds most closely to evolutionary biology and the modern synthesis.
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[edit] Definitions
The concept of the "kind" originates from a literal reading of Genesis 1:12-24:
- And God said, let the earth bring forth grass, the herb yielding seed, and the fruit tree yielding fruit after his kind … And God created great whales and every living creature that moveth, which the waters brought forth abundantly after their kind, and every winged fowl after his kind … And God said, let the earth bring forth the living creature after his kind, cattle and creeping thing, and beast of the earth after his kind, and it was so.
In 1941, creationist writer Frank Lewis Marsh proposed that the Biblical created kind could be defined in terms of reproduction. He argued that as long as two modern creatures can hybridize with true fertilization, the two creatures are descended from the same kind. This idea has been adopted to support the practice of baraminology, the attempt to classify created kinds. Creation scientists posit that kinds are a form of clade, in that a posited kind displays evidence for common lines of ancestry among its member organisms.
Microbiologist and creationist Siegfried Scherer refined the criteria to state that if two creatures can hybridize with the same third creature, they are all members of the same "basic type". Thus all members of a ring species would be members of the same basic type. Scherer also updated Marsh's explanation of true fertilization:
- Two individuals belong to the same basic type if embryogenesis of a hybrid continues beyond the maternal phase, including subsequent co-ordinated expression of both maternal and paternal morphogenetic genes.
There is some uncertainty about what exactly the Bible means when it talks of "kinds". The original Hebrew word used is min, which is used to describe a variety of organisms. Russell Mixter, another creationist writer, comments that
- One should not insist that "kind" means species. The word "kind" as used in the Bible may apply to any animal which may be distinguished in any way from another, or it may be applied to a large group of species distinguishable from another group ... there is plenty of room for differences of opinion on what are the kinds of Genesis. [1]
"Creation science" proponents posit that the defining element of kinds is creationist-approved evidence for common lines of ancestry among the organisms in the posited kind. The few creationists who work to make the classifications have not so far come up with a consistent set of rules for establishing when this criteria is met. As such, kinds do not coincide with any particular level of taxon. In some cases, such as humanity, kinds coincide with species or genus. In other cases, such as Felidae, they may be equivalent to the family level of taxonic classification.
[edit] Kinds in the Tree of Life
The creationist "kind" is assumed to be based upon an idea that life in the past exhibited greater genetic diversity and heterozygosity than life today, in the form of "kinds" analogous to the liger. Thus, the kinds were created with the innate ability to vary a great deal, and subsequent evolutionary processes are merely the means by which that innate ability to vary is expressed.
The definition of created kinds is therefore similar in form and function to the phylogenetic tree of evolutionary biology, but bears two important differences.
- First, while the phylogenetic tree traces life back to a single cell or population of single-celled organisms, creation biology traces life back to a large number of unrelated populations of life-forms which roughly resembled the forms of life today, effectively stating that there are no biological connections beyond the very tips of the phylogenetic tree.
- Second, while the pylogenetic tree credits evolutionary change to a diversification and specification of lifeforms through processes such as natural selection, creationists credit microevolutionary change to the rearrangement and expression of genetic variation that was "built in" to the original kinds.
Change in created kinds is said to take place through an unspecified process that is said to be "degradation of the genome", as natural selection and reproductive isolation, inbreeding, and genetic drift caused lifeforms to adapt to their environment by the loss of capacity to adapt to other environments. Speciation is held to be a side-effect of a degrading genome, and most is said by creationists to have occurred during and after the rapid dispersion immediately after a global flood that is reported to have occurred in Genesis. This event is said to have caused an extreme population bottleneck which caused the major speciation events taking place within the space of 1000 to 2000 years after the flood. In effect, this requires an evolutionary process that is faster than modern biology's timescales for speciation. This explanation also relies on the assumed fact of a global flood (see flood geology), an event for which neither mainstream biology nor geology has found any evidence.
Many creationists believe that the formation of the races was a result of so-called "degradation of the genome". The population onboard the ark is believed to have been a hybrid population containing the genetic characteristics of all the races. When the population spread over the Earth after the flood, gene pools became isolated resulting in the races. This view is not supported by the genetic evidence surrounding race, which is that there is more genetic variation within the races than between the races.
The differentiation of species from original hybrids is the heart of the concept of created kinds. Hybridization as a genetic concept is technically rejected since creationists believe a hybrid is less, rather than more, degraded, with regard to its parents.
[edit] Boundaries between kinds
The asserted boundaries between the kinds -- the position that the kinds are unrelated -- is arguably the most divergent view of creationists from mainstream biology. Those challenging creation biology often ask what basis creationists have for asserting that such boundaries exist, or for determining what those boundaries are.
The project of determining the precise boundaries between the kinds is not agreed upon by creationists. Creationists generally assert that conclusions about common ancestry should only be drawn if there is "substantial evidence" to support the conclusion. As to what qualifies as "substantial evidence", creationists are often at odds with each other. However, they are in unanimous agreement that humans and other extant primates are not in the same kind.
In the absence of the ability to directly observe life in its original form, classification of kinds generally revolves around reproductive compatibility -- that is, created kinds are generally seen as having common descent if they are reproductively compatible.
The classification is more difficult when reproductive compatibility is partial, as in the case of the mule, a hybrid of the horse and the donkey which, although viable, is not fertile. While it is possible that the two species descend from a common ancestor due to their reproductive compatibility, it is also possible that they do not, but were created separately with reproductive systems similar enough to create viable offspring, but not similar enough to create fertile offspring.
Other criteria for common ancestry are rejected. The mere fact that organisms are alive is not seen as evidence of common ancestry. Genetic and physiological similarities are not seen as evidence of common ancestry, but rather are thought to result from a similar design being used on different "kinds." There is normally no justification offered as to why reproductive compatibility shouldn't be viewed in the same way, though there are references made to biblical verses such as "go forth and multiply" -- the command given by God to Noah's family after the flood.
Since 2001, a new method has been discussed for demarcating created kinds via baraminology. The new method involves the application of morphological character data to create a "biological character space," which can then be used to determine continuity and discontinuity between species, and ultimately to determine "biological trajectories." This method is discussed in greater detail in the article Baraminology.
[edit] Hypothesized kinds
Creationists have proposed a handful of possibilities for the created "kinds":
- Humanity — Creationists reject any and all claims of evidence for a common ancestor between homo sapiens and other great apes. Creationist Sigrid Hartwig-Scherer concluded that H. erectus/ergaster, Neandertals and H. sapiens were members of the same basic type (which corresponds to a monobaramin) Homininae with the fossils called Australopithecus afarensis, A. anamensis, A. africanus, A. robustus, A. aethiopithecus, A. boisei and possibly Ardipithecus ramidus assigned to another basic type, Australopithecinae.
- Felidae — Creationists from Answers in Genesis and the Institute for Creation Research have proposed that the original kinds were comparable to the Liger and the Tigon.
- Canidae — Similar to the kind associated with cats, it is proposed that all canines had a common ancestor.
- Camelidae — Including both the camel and the llama, which are reproductively compatible, their hybrid offspring being known as "Camas".
- Crocodilia — Including all the varieties of alligator, crocodile, and gharial.
- Elephants: African elephant (Loxodonta africana) and Asian elephant (Elephas maximus) can mate and produce offspring, albeit short-lived, although they are officially classified as different genera.
Thus the created kind corresponds roughly to the family, and possibly even the order with the notable exception of humanity.[2]
Creationists also point to known examples of hybridization to argue that the kind is broader than the biological species, and sometimes even than the genus. For example:
- Kekaimalu the wholphin is a fertile hybrid of two different types of dolphin, the false killer whale (actually a kind of dolphin), and bottlenose dolphin. Kekaimalu herself gave birth to a calf, showing she was a fertile hybrid. Thus these creatures classified as different genera are really a single polytypic (many-type) species.
- Bos (true cattle) and Bison (American buffalo) can produce a fertile hybrid called a cattalo. Bos and Bison are thus likewise the same polytypic species although they classified as different genera.
- The creationist Don Batten helped create a hybrid of the fruit species lychee (Litchi chinensis) and longan (Dimocarpus longana), again classified as different genera.
A canonical list of kinds has not been constructed and such examples are extremely provisional (with the exception of humans, on which there is a strong creationist consensus).
Creation biology looks to the animals visible in the fossil record (which creationists interpret as having mostly been laid down during the flood) as evidence that antediluvian life was much more diverse than life today. They reject the dating methods of paleontologists and geologists that determine the age of fossils from the order of the fossil record and instead believe that almost all fossils were deposited in a single catastrophic flood event and were sorted out by processes associated with the flood. (See flood geology for more on this topic.)
