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There are more than 2700 species of snakes in the world. The evolutionary and creationism models make predictions on what kind of groups these species can be divided into. Which is supported by the actual evidence?

EVOLUTIONARY MODEL

If evolution has occurred, then the relationships among modern snakes should form a nested hierarchy showing degrees of varying relatedness.

CREATIONISM MODEL

If the creationism model is correct, then the only taxonomic unit which is valid is that of "kind". Each "kind" is completely unrelated to every other "kind" since no two "kinds' share a common ancestry. Each "kind" of snake would have been in existence since the first week of life on earth.

INTELLIGENT DESIGN

If intelligent design has occurred, then some/substantial evolution could have taken place in snake lineages. However, each separate "design" should be impossible to develop over time.

boa boa

ALthough there are a number of groups of legless vertebrates in the modern world and the fossil record, a number are classified as "snakes" because of the features that they share. Snake skulls are lighter than those of other reptiles and the bones are not as tightly secured to each other.  Snakes can’t chew because the ability to chew would restrict the size of the prey they could eat.  Their upper jaws not fused to each other or to the braincase.  The mandibles not fused to each other but instead are joined by an elastic ligament.  Teeth exist on the maxillary, palatine, and pterygoid bones of the upper jaw and the teeth of most snakes similar in size and shape (Mattison, 1995).

jaw

Male lizards and snakes possess a pair of penises, called hemipenes.

hemipenes

     There are creationists who accept the possibility that snakes form a single "kind" and that thus all modern snakes are descendants from a common ancestor. This view would not be undermined by evidence supporting the classification of snakes into a nested hieararchy of related groups.  If snakes, however, represent multiple "kinds", then these "kinds" would be as unrelated to each other as snakes are to all other organisms (including legless lizards, worm lizards, caecilians, worms, etc.). The anatomical and molecular evidence collected by those who have studied snakes support their classification in a nested hierarchy of related groups, rather than discrete unrelated groups.

The first division of modern snakes is the separation of the Scolecophidia (blindsnakes and thread snakes) from the Alethinophidia (all other snakes). A blind snake is depicted below.

Typhlops brongarsmianus

BLIND SNAKE cladogram

THREAD SNAKES

Leptotyphlops australis

THREAD SNAKELeptotyphlops anguirostris THREAD SNAKE

ALETHINOPHIDIA

This second group (Alethinophidia) can be divided into dwarf pipesnakes and the group Macrostomata which composes all remaining snakes.  Thread snakes are a group of primitive snakes is found throughout Latinamerica, Africa and the Middle East.  These small snakes retain pelvic girdles and spur-like vestigial legs.    They are burrowing snakes which feed on termites.

Only the most primitive snakes possess uniform scales which cover their entire bodies, higher snakes developed ventral scales whichare larger than other scales.  All blindsnakes feed exclusively on invertebrates, primarily on eggs and the larvae of termites and ants.  Their jaws are not as extensible as those of higher snakes (Mattison, 1995).   Macrostomatans developed greater jaw mobility as they adapted to eating larger prey items (Greene, 1997).

MACROSTOMATA

Macrostomata can be divided into the most primitive forms (4 families of boas and pythons; a boa constrictor is pictured in the adjacent image) and advanced snakes composed of filesnakes and the higher snakes classified as Caenophidia. 

boa

groups of snakes

Higher snakes are classified as the group Caenophidia which in turn can be divided into the family Acrochordidae and the large group Colubroidea.

COLUBROIDEA

The Colubroidea forms the largest group of snakes and includes vipers as its basal group, the venomous elapids (cobras, sea snakes, and coral snakes), and the harmless snakes of the family Colubridae. The families Elapidae and Atractaspididae may have evolved from within the family Colubridae.

cladogram

Anatomical studies and molecular studies indicate that these families can in turn be divided into a nested hiearchy of subfamilies and genera (Lawson, 2005, Slowinski, 2002, Gravlund, 2001; Noonan, 2006; Pugh, 1998; Greene, 1997).

CREATIONISTS CANNOT AGREE ON HOW TO CLASSIFY SNAKES INTO "KINDS"

The Bible can not be used to classify the thousands of snake species into groups since there are only two words for "snake": viper (akshub) and cobra (pethen), (Pinney, ).

What level of snake classification do creationists identify with the "kind"? Despite the use of the word "kind" for thousands of years, there is absolutely no modern consensus on how it could be used to classify modern organisms such as snakes. For the most of the past millenium, "kind" was considered to be roughly equivalent to "species". Because biologists have provided strong evidence that species do evolve from other species, very few modern creationists would equate the "kind" with species. Is a "kind" equivalent to the taxonomic category of genus? subfamily? family? order? Modern creationists cannot agree. Certainly, there is no evidence that one of these categories of snake classification is qualitatively different from the others (i.e. that some are real and others are contrived terms which attempt to depict a relationship which simply doesn't exist).

There is no evidence to support that snakes can be divided into the creationist category of "kinds". The families of snakes can be divided into superfamilial groupings which are not equally related but form instead a nested hierarchy of relationship. The families of snakes, the subfamilies of snakes, and the genera of snakes also provide evidence of a nested hiearchy rather than eqully unrelated "kinds". In this nested hierarchy, variation does not suggest instances where intelligent design interrupted natural processes of descent with modification.