Geoscience Research Institute

IN A FEW WORDS

Origins 13(1):3-4 (1986).

Brief summaries of the main conclusions of the leading presentations are given below for those who may find the complete articles too long or technical.

A CREATIONIST VIEW OF CHROMOSOME BANDING AND EVOLUTION

    Similarities in organisms are commonly interpreted as the result of a common ancestry. Since chromosomes are the carriers of heredity, similarities in chromosomes could have special significance in studying the ancestry and relationships of species. Many studies comparing chromosomal banding patterns have been conducted. Through the use of a special staining technique, chromosomes can be stained to show a pattern of alternating dark and light bands. The detail of the pattern depends on the length of the chromosome at the time it is stained. If sufficient detail is present, each pair of chromosomes in a cell can be distinguished. Chromosomes from different species can be stained and then compared and contrasted. Similarities and differences maybe interpreted subsequently as reflecting the degree of relationship.
    Although there are some interesting exceptions, comparisons of chromosomal banding patterns are generally consistent with comparisons based on other criteria. Species within a family generally show considerable matching of chromosome banding patterns. The cat, camel, and cow families each have substantial intrafamilial similarities in chromosomal banding patterns. On the other hand, some species have banding patterns which differ greatly from those of other species in the same genus. Similar species with different chromosomal banding patterns are found among certain deer (the muntjacs) and bats (Family Phyllostomidae).
    More problematic are the similarities in chromosomal banding patterns among species which are different in structure. Interfamilial chromosomal banding similarities are found among the cats, mongooses, and raccoons; among the cow, deer, and giraffe families; among several families of marsupials; and among several families of primates, including humans. This raises questions about the extent of change which may have occurred in mammals, as well as the relationship of humans to other primates.
    Four hypotheses to explain similarities of chromosomal banding are discussed in this paper. Such similarities could be the result of common design, of common ancestry, of chance, or of the action of virus-like agents. The hypothesis that chromosomal similarities could be due to chance seems unreasonable, It seems more likely that virus-like agents would cause differences between karyotypes than that they would change different karyotypes to look similar. Common ancestry appears to be the most likely basis for chromosomal similarities in species classified in the same genus, and for some species classified in different genera. However, to extend this explanation to higher taxonomic categories, in which similarities are of lesser extent and of lower quality does not seem necessary. To a creationist, it seems more probable that chromosomal similarities such as are found within the artiodactyls, the carnivores, the marsupials or the primates may be the result of common design.

RECENT DEBATE OVER ARCHAEOPTERYX

    Archaeopteryx is considered to be an important example of a missing link between two major classes of animals. It has been subjected to much controversy since its discovery over a century ago. Recently, a group of physicists challenged the authenticity of the plumage of Archaeopteryx. They suggested that feathers were artificially impressed on a thin layer of cement which was applied to the skeleton of a flying reptile. In response to the challenge, paleontologists from the British Museum (Natural History) conducted a series of tests on the holotype of Archaeopteryx. They found no evidence of a cement layer on the fossil. Nevertheless, the history associated with the two best Archaeopteryx fossils leaves some unanswered questions concerning their authenticity.