GEOSCIENCE REPORTS

Fall 1990, No. 12

SPECIES ON ISLANDS: Evidence for Change
L. J. Gibson, Geoscience Research Institute

The Significance of Islands

    In the early development of the theory of evolution by natural selection, two men stand out as having played a central role: Charles Darwin and Alfred Wallace. Both men traveled widely and were keen observers of nature. For both men, visits to islands played an important role in developing their understanding of nature. Darwin's visit to the Galapagos Islands is of special interest.
    The Galapagos Islands are located about 1000 km west of Ecuador, South America. The largest island is Isabela, about 4670 km², rising to 1680 m. Volcanic activity continues into the present, fresh water is scarce, and many arts of the islands are desert-like. When Darwin visited the islands in 1835, he was impressed with the unusual composition of the flora and fauna. Having taken a theology course in England, Darwin apparently believed that God had specially created each species for its present habitat and that no changes could occur in the species. The flora and fauna of each area on earth had supposedly been designed specifically for that area.

FIGURE: The unusual cactus fauna of one of the Galapagos Islands. These are volcanic islands far removed from the nearest continents.

    The fauna of the Galapagos Islands did not seem to fit with Darwin's expectations. There are no freshwater fish or amphibians native to the islands, and hardly any mammals, although suitable habitat for mammals is available. Many of the birds and reptiles are distinct species, yet look similar to those of South America, from where Darwin had just come. Giant tortoises, a species of snake, and several kinds of lizards live on the islands, each with probable ancestors in South America. The iguanas belong to genera that are endemic (restricted in distribution) to the Galapagos Islands. The other lizards on the islands are endemic only at the species level. The birds include several subspecies of South American derivation, as well as a group of finches named after Darwin (see Lack 1983). There are about 13 species of Darwin's finches, divided into three genera and forming an endemic group variously classified as a subfamily or tribe. A flightless cormorant is also present.
    Understandably, Darwin was puzzled as to why God would create such an odd assembly of animals for the Galapagos, and why they should be similar to the species living in South America. As he considered the evidence he had seen, Darwin concluded that the species on the Galapagos had originally come from South America and had changed since arriving in the islands. To explain how animals could change and how such peculiar distribution patterns could come about occupied Darwin's attention for many years after his return to England. The result was publication of his famous book The Origin of Species, which presented his theory of evolution of species by natural selection. The study of the fauna of islands thus played an important part in the development of evolutionary theory.

Characteristics of Islands

    One of the most important characteristics of islands is their geology. Islands may be formed by different geologic processes. Some islands are actually parts of a continent, separated from the main landmass by shallow water. There is evidence to suggest that these islands were once part of the mainland. It appears that large areas, especially of the northern continents, were once covered by extensive ice sheets and inland seas. At this time, sea level appears to have been as much as 100 in lower than at present. As a result, many present-day islands were part of the mainland. Examples of this kind of island include Trinidad, the British Isles, and Borneo. A second type is the volcanic island that formed in deep water and never has been connected to any large landmass. Examples include the Galapagos Islands and the Hawaiian Islands. The Seychelles Islands in the Indian Ocean and a few other groups represent a third type that is composed partly of continental granitic rocks and partly of volcanic rocks. They may represent continental fragments resulting from the breakup of continental plates. Larger continental fragments compose the islands of Madagascar and Australia. Finally, a fourth type of island is found in archipelagos fringing the edge of a continental shelf. They are mainly volcanic, with some limestones. The West Indies, the Philippines, and the Lesser Sundas are examples of fringing archipelagos.
    Biogeographically, islands may be classified as either oceanic or continental. Oceanic islands typically have faunas that are ecologically and taxonomically unbalanced (incomplete). Colonization of these islands is by some form of overwater dispersal. Continental islands generally have a more complete and balanced fauna that fills the available habitats and closely resembles that of the adjacent mainland portion of the continent. Separation of continental island and mainland terrestrial faunas is due to division of pre-existing faunas (vicariance) rather than to overwater dispersal.
    The study of islands can provide evidence relating to several important questions such as speciation, methods of dispersal, and past events. It seems obvious that the distinctiveness of species on isolated volcanic oceanic islands must be a result of change in species. Distribution patterns indicate the relative dispersal abilities of organisms under past conditions. By comparing the characteristics of faunas from different types of islands, we may be able to improve our understanding of the history of our world.

Faunas of Volcanic Islands

    The Galapagos Islands, discussed above, are a group of volcanic islands. In comparing the fauna of the Galapagos Islands with those from other volcanic islands, certain patterns emerge.
    The faunas of isolated volcanic islands are not balanced, either ecologically or taxonomically. The same types of organisms, particularly birds, lizards and rats, are often found on many different oceanic islands, showing that they disperse over water readily. Strictly freshwater fish and amphibians are absent or very rare, as are most kinds of mammals. Rats occasionally may have rafted to islands, but transport by humans is probably also an important factor. Snakes are also rare, but lizards are fairly common. The greatest diversity of vertebrates on volcanic islands is among the birds. Isolated groups of islands may have species groups that are distinct enough to be classified as a separate tribe or subfamily. Most isolated islands have, or did have, one or more species of flightless birds.

Faunas of Some Continental Shelf Islands

    Trinidad is an island lying on the northeastern edge of the South American continental shelf. Trinidad has an area of 4845 km², a maximum elevation of about 925 m, and is separated from the mainland by about 16 kin. The island is inhabited by seven families and 10 subfamilies of amphibians and a wide variety of reptiles (Maclean et al. 1977). Many species of birds (Herklots 1961) and mammals (Vesey-Fitzgerald 1936) are present. Among the mammals are two species of monkeys, many kinds of rodents, several carnivores, a species of deer, a peccary, three edentates, and about four marsupials. The faunal diversity of Trinidad is far greater than the faunas of remote volcanic islands, and the distinctiveness is much less. No vertebrate genera, and only a few species, are endemic to Trinidad.
    The close similarity of the fauna of Trinidad with that of the mainland, the separation by shallow water, the presence of strictly freshwater fish and amphibians, and the ecological and taxonomic balance of the fauna all support the concept that the island was once part of the mainland.
    Several factors contribute to the differences between the faunas of continental islands such as Trinidad as compared with those of volcanic islands such as the Galapagos. Volcanic islands tend to be smaller and less ecologically diverse than continental islands, and so cannot support as many species. However, although the island of Hawaii is over twice the size of Trinidad and is ecologically diverse, Trinidad has a much greater faunal diversity.
    The origin of the island and the degree of its isolation seem to be the most important factors affecting the faunal diversity. Faunas of continental islands are primarily derived from overland dispersal, rather than from overwater dispersal. As the Pleistocene continental ice sheets melted, rise of sea level divided what was one fauna into two vicariant faunas. This means that the continental islands once had a mainland fauna, with some extinctions occurring after the island was isolated. The faunas are limited by climate and area, but not by distance to the mainland or by method of dispersal. Volcanic islands have never had a balanced fauna, but are populated only by those species that chanced to reach there. Their faunas are limited by climate and area, and also by distance to a mainland and dispersal method.

Islands that are Continental Fragments

    Nearly all small oceanic islands are volcanic, but there is one interesting exception, the Seychelles Islands. This group of granitic islands lies in the Indian Ocean between Madagascar and India. The islands are separated from each other by relatively shallow water, and it seems likely that the islands were once connected into a large island with an area perhaps as great as 31,000 km² (Stoddart 1984). The largest island, Mahe, has an area of 145 km² and reaches 914 m elevation, the highest peak in the islands. The nearest faunal source for the Seychelles is Madagascar, 930 km distant. The distance to East Africa is nearly 1600 km, and India is over 1700 km to the northeast.
    The fauna of the Seychelles lacks strictly freshwater fish and land mammals, except for a few species of bats (Darlington 1957). The islands are richer in amphibians than one would expect on such isolated islands. Of the 12 species, 11 are endemic. These include a family of frogs, the Sooglossidae, and three genera and seven species of caecilians, worm-like amphibians found only in the tropics. Nine of the 18 species of lizards, but none of the genera, are endemic (Gardner 1986). Two species of snakes (family Colubridae, to which most snakes belong) are present, one of which forms an endemic genus (Darlington 1957). The most spectacular members of the fauna are undoubtedly the giant tortoises, now much reduced in range. A freshwater turtle (family Pelomedusidae) also inhabits some of the islands, but it may have been introduced by man. Nile crocodiles were present at one time, but are now extinct on the islands. Several endemic species of birds inhabit the islands, with few if any known extinctions. The caecilians and the sooglossid frogs are of uncertain origin, but the other frogs and most of the rest of the fauna are related to species in Africa or Madagascar (Nussbaum 1984).
    From this limited information, it can be seen that continental fragments have unbalanced faunas much as volcanic islands do. The major differences may be due to island size and distance from a source area. Continental fragment islands are usually larger and not as isolated as, for example, the Hawaiian Islands. Australia is an island continent and has a low diversity of freshwater fish and a high degree of endemism of its vertebrates. The faunal origins of continental fragment islands, especially Australia, are sometimes unclear. Groups with puzzling ancestries include the sooglossid frogs of the Seychelles, the marsupials and monotremes (egg-laying mammals) of Australia, the iguanid lizards of Madagascar and the kiwis of New Zealand.

Fringing Archipelagos

    Island archipelagos along or just beyond the edge of a continental shelf are a fourth island type, the fringing archipelago. Examples of this kind of island are the Philippine Islands, the Lesser Sundas, and the West Indies. Geologically, the West Indies are principally volcanic, with a mixture of mostly marine sediments (Woodring 1964). These islands are separated from both North and South America by deep water and are biogeographically oceanic. The largest island is Cuba, with an area of nearly 115,000 km². The highest peak, about 3100 m, and the greatest habitat diversity are on the island of Hispaniola (shared by Haiti and the Dominican Republic). These two islands plus Jamaica and Puerto Rico comprise the Greater Antilles. A double arc of volcanic islands, the Lesser Antilles, extends from Puerto Rico toward the coast of South America.
    Biogeographically, the West Indies are oceanic, in agreement with the fact that they are separated from the continents by deep water. The vertebrate fauna of the West Indies is unbalanced, although there is a reasonable diversity of birds (Bond 1978). Of the seven amphibian genera, three are endemic to the West Indies (Schwartz 1978). The largest group of frogs belong to the genus Eleutherodactylus, which has no tadpole stage.
    Reptiles are well represented in the West Indies, with a total of 55 genera (Schwartz 1978). Most families of New World snakes and lizards are represented, with five genera of lizards and six genera of snakes endemic to the region. Only one genus of freshwater turtle and one genus of crocodile are native to the West Indies.
    Among the mammals (see Varona 1974, Hall 1981) there are no native marsupials, hoofed mammals or carnivores. Raccoons, agoutis and rice rats are present on some islands, but the pattern of distribution suggests human transport. With these exceptions, all terrestrial mammals known from the islands (except bats) are endemic. This includes two families of insectivores, a family of ground sloths, and several genera of rodents, including two families. The ground sloths, one family of insectivores, and several of the rodents are now extinct. The rodents and ground sloths are most similar to South American species. The insectivores seem to be from North America, but their origin is an enigma (see MacFadden 1980). The birds are North American, while the reptiles are South American (Maglio 1970). Distributional patterns suggest the main route has been from Central America through Jamaica, even though this is not the shortest route (Briggs 1984, Darlington 1937, Gill 1978). If sea level were lowered some 100 m, as is believed to have occurred in prehistoric times (Milliman & Emery 1968), the distance from Central America to Jamaica would be reduced to about 400 kin. More importantly, certain submerged banks would then be above water, and the greatest required overwater dispersal distance would be less than 150 Ian. Nevertheless, the obstacles to dispersal would be considerable. The area seems to have a history of tectonic activity, and the geography may have been different during the time dispersal was occurring. The possible effect of prehistoric man on these distributions is unknown.

FIGURE: Taal crater lake and crater (right). The Philippine Islands are representative of fringing archipelagos.

Taxonomic Distribution Patterns

    Different groups of vertebrates have different distribution patterns on islands. Strictly freshwater fish are absent on islands except those on continental shelves. Even Australia has very few primary freshwater fish. Amphibians are generally absent on volcanic islands, although some are present in the West Indies, and from Australia to as far as Fiji in the Pacific. Salamanders are generally not found on islands, except for a few continental shelf islands. Frogs are found on many islands, especially those having continental rocks. Island-dwelling frogs often seem to have direct larval development; that is, there is no tadpole stage but the eggs hatch into little "froglets". This feature may facilitate island colonization by making the frogs less dependent on permanent water supplies. Caecilians are found on some oceanic islands, such as the Seychelles and Cuba. Their dispersal method is unknown, but they are burrowers and perhaps could raft inside rotting logs.
    Reptiles, especially lizards, are common on islands. Lizards are small and cling easily to floating vegetation, and it is generally believed they are good rafters. However, lizards are probably also easily transported by man, either intentionally or accidentally. Snakes are uncommon on islands. The most widespread snakes are small burrowers and might be able to raft in rotting logs. It seems surprising to find giant tortoises on islands, but perhaps they can simply float on currents far out to sea.
    Birds and bats can fly to islands; so there is less of a problem imagining how they could arrive at nearly any point on earth, especially if carried by storms. Land mammals are essentially absent from volcanic islands, except for rodents, which could have been accidentally transported by man, or rafted on mats of vegetation. Of the 66 families of mammals that are restricted in distribution to no more than a single continent, 25 families are restricted to islands (including Australia). The mammal faunas of the West Indies, Madagascar and Australia are highly endemic, and the origins of some groups are obscure.

Changes in Island Species

    Island species often differ in size from closely related continental species. Small species are often larger, while larger species are often smaller on islands, although these tendencies do not always hold (Lawlor 1982). Traits other than size may also be involved, sufficient to justify classification in separate genera or higher taxa. In some cases, plausible ancestry of endemic insular genera can be postulated from the mainland fauna, (e.g., Wyles & Gorman 1978). In other cases, such as the duck-billed platypus, the origins of an endemic group are unknown.
    It is generally assumed that the more distinctive a species is, the older it must be. However, this may not be true. The distinctiveness of species on isolated oceanic islands may be a reflection of the degree of isolation rather than the amount of time involved. Without competitors or predators, aberrant individuals might survive and give rise to a new species able to adapt to a different ecological niche. Such species might be expected to be vulnerable to extinction if competitors or predators were to become established in their habitat. This may help explain why many island species have become extinct or are endangered as man and his associated animals move in.
    The question of the extent to which species are able to change is of considerable interest to creationists. Island species may provide a useful indication of the natural limits to change. It appears that significant changes in species have occurred but the evidence is circumstantial rather than demonstrable. The evidence suggests that new species and new genera, have been produced many times. Madagascaran primates appear to have changed enough to be classified in different families. Of course, whether a species is classified in a new genus or a new family, etc., depends on the subjective judgment of a taxonomist. Since higher taxonomic categories are not based on any objective criteria, no particular taxonomic category can be taken to represent the limits of change in species. Each case must be examined individually. However, it is noteworthy that no new structures have originated in island species. Changes have been by modification of previously existing structures. Island species provide evidence for change in species, but do not show any evidence of the origin of new morphological structures or an increase in complexity.

Summary and Conclusions

    Island faunas are of two types. Continental shelf islands have faunas that are balanced both ecologically and taxonomically, with species number depending on size and habitat availability. Species are generally not very distinct from those on the mainland. Dispersal to continental islands probably occurred during periods of lowered sea levels, when there was land connecting the island with the mainland.
    Isolated oceanic islands typically have many empty niches and only a few taxonomic groups are represented. Colonization of such islands must have been by overwater dispersal. Whether this occurred during periods of lowered sea level is not known, but seems plausible. Overwater dispersal of land vertebrates appears to be quite rare under present conditions. Groups of oceanic islands and large islands often have one or more taxonomic groups that appear to show adaptive radiation, with species often distinct enough to be classified as separate genera or even families. In some instances, it is difficult to determine the closest relatives of groups of species that have undergone such extensive changes, or to determine whether they may be the only surviving relicts of some previously more widespread group.
    Different kinds of organisms differ in their ability to disperse to islands. Birds and bats have the greatest dispersal abilities, followed by lizards and rats. Amphibians and strictly freshwater fish are the poorest dispersers to islands. The amount of change occurring in species on an island seems related to the degree of isolation of the island. Both the frequency of endemism and the taxonomic level involved are lowest in those groups that are good dispersers, such as bats and birds, and higher in groups of rare dispersers such as reptiles and mammals. Changes in island species can only be inferred, not observed. Though they suggest that the morphology of a species can be significantly modified, there is no evidence for the origin of new structures or any increase in complexity.

Literature Cited

• Bond,J. 1978. Derivations and continental affinities of Antillean birds. In F. B. Gill (ed.), Zoogeography in the Caribbean, pp. 119-128. Spec. Publ. No. 13. Acad. Nat. Sci. Phila.
• Briggs, J. C. 1984. Freshwater fishes and biogeography of Central America and the Antilles. Syst. Zool. 33:428-435.
• Darlington, P. J. 1937. The origin of the fauna of the Greater Antilles, with discussion of dispersal of animals over water and through air. Quart. Rev. Biol. 13:274-300.
• Darlington, P. J. 1957. Zoogeography. John Wiley, New York.
• Gardner,A.S. 1986. The biogeography of the lizards of the Seychelles Islands. J. Biogeog. 13:237-253.
• Gill, FB. (ed.). 1978. Zoogeography in the Caribbean. Acad. Nat. Sci. Phila., Spec. Publ. No. 13.
• Hall, E. R. 1981. The mammals of North America. John Wiley, New York.
• Herklots, G. A-C. 1961. The birds of Trinidad and Tobago. Collins, London.
• Lack, D. 1983. Darwin's finches. Rev. ed. Cambridge Univ. Press, Cambridge.
• Lawlor, T. E. 1982. The evolution of body size in mammals: evidence from insular populations in Mexico. Am. Nat. 119:54-72.
• MacFadden, B.J. 1980. Rafting animals or drifting islands?: biogeography of the Greater Antillean insectivores Nesophontes and Solenodon. J. Biogeog. 7:11-22.
• Maclean, W. P., et al. 1977. Island lists of West Indian amphibians and reptiles. Smithson. Herpet. Info. Serv. No. 40.
• Maglio, V. J. 1970. West Indian xenodontine colubrid snakes: their probable origin, phylogeny, and zoogeography. Bull. Mus. Comp. Zool. 14:1-54.
• Milliman, J. F. & K. O. Emery. 1968. Sea levels during the past 35,000 years. Science 162:1121-1123.
• Nussbaum, R. A, 1984. Amphibians of the Seychelles. In D. R. Stoddart (ed.), Biogeography and Ecology of the Seychelles Islands, pp. 379-415. junk, The Hague, Boston, Lancaster.
• Schwartz, A. 1978. Some aspects of the herpetogeography of the West Indies. In F. B. Gill (ed.), Zoogeography in the Caribbean, pp. 31-51. Acad. Nat. Sci. Phila. Sp. Publ. No. 13.
• Stoddart, D. R. 1984. Scientific studies in the Seychelles. In D. R. Stoddart (ed.), Biogeography and Ecology of the Seychelles Islands, pp. 1-15. Junk, The Hague, Boston, Lancaster.
• Varona, L. S. 1974. Catalogo de los marniferos vivientes y extinguidos de las antilles. Acad. de Ceincias de Cuba.
• Vesey-Fitzgerald, D. 1936. Trinidad mammals. Tropical Agric. 13:161-165.
• Woodring, W. P. 1964. Caribbean land and sea through the ages. Bull. Geol. Soc. Amer. 165:719-732.
• Wyles, J. S. & G. C. Gorman. 1978. Close relationship between the lizard genus Sator and Sceloporus utiformis (Reptilia, Lacertilia, Iguanidae): electrophoretic and immunological evidence. J. Herp. 12:343-350.

SCIENCE NEWSNOTES

NATIONAL PARK ESTABLISHED IN NEVADA

    Great Basin National Park was established in 1986 in Eastern Nevada, 65 miles east of Ely. Although Lehman Caves National Monument has been under the protection of the Department of Agriculture or the National Park Service since 1922, the new 120 mi² park also includes part of the high Snake Range that culminates in Wheeler Peak, 13,063 ft., the highest in the Great Basin. Nestled in a glacial cirque is the southernmost active glacier in North America. Ancient Bristlecone Pines, some with over 5000 rings, guard high slopes of this range which rises like an island from the surrounding sagebrush desert. A paved road gives access to the high country above 10,000 feet.
    Sometime in the 1870's, Ab Lehman's horse fell into a natural opening, leading to the discovery of a marvelous labyrinth of passages named Lehman Caves after the old homesteader. Although the higher elevations of Wheeler Peak are quartzite and granite, a thick deposit of Cambrian limestone, later intruded by granite, lies at the eastern base of the mountain. Lehman Caves are among the most beautiful in North America. Unique among a wide variety of cave formations are the plates or shields from which hang curtains and folds.
    Great Basin National Park, the only National Park in Nevada, stands with the other National Parks as a worthy guardian of outstanding unspoiled scenery, unusual geological formations, and native animals, including mountain lions, mule deer, coyotes as well as a good variety of birds. As human populations grow such oases will become increasingly important.

FIGURE: The Tyrrell Museum of Paleontology (only part showing in this photo) is located near the city of Drumheller, Alberta, Canada.

TYRRELL MUSEUM OF PALEONTOLOGY

    In 1985 the province of Alberta, Canada, opened the Tyrrell Museum of Paleontology. This world-class museum, one of the finest for paleontology in North America, is situated among the badlands near Drumheller, (90 miles northeast of Calgary). This small town may seem like an unlikely place for the placement of a major museum but it must be noted that the Red Deer River, on which the town is located, has been famous for dinosaurs since before the turn of the 20th century.
    A striking feature of this museum is a skywalk where the viewer can gaze down into a huge room of giant reptiles from the past. Eastern Alberta has furnished many specimens of both Mesozoic reptiles and Tertiary mammals. Some of these remains, along with casts of some of the more famous fossils exhibited in other museums, have been mounted or displayed with appropriate backdrops. From the elevated viewpoint, the visitor can make his way down to the walkways that lead among and past these spectacular specimens. Conveniently placed benches provide a moment of rest while video screens gives additional information on microfossils, collecting methods, or conflicting theories. Attached to the museum is an arboretum containing living relatives of fossil plants.
    This is no museum of dusty specimens and aging discolored labels. Elegant maintenance is evident and there is an aura of class and authority. Scientists trained in various aspects of paleontology are employed not only to operate the museum but to undertake research on the museum collections and in field sites throughout the West. Presently a major dinosaur project is being pursued in cooperation with the People's Republic of China.
    No admission is charged although a donation of $2.00 per person is suggested. Any visitor to Alberta would be well rewarded by including a trip to this museum in his plans.

MAY I ASK A QUESTION?

How do creationists relate to the current theory of drifting continents?

    The theory of continental drift (now more correctly called plate tectonics because the moving plates may or may not incorporate continents) has stimulated a major revolution in geology. Twenty years ago few accepted this mind-boggling idea but now the tables are turned — most geologists accept it in principle.
    Critical examination of the evidences for matching coastlines, paleomagnetic lineations on both sides of spreading centers, correlations of geology for areas once thought to have been together, plates plunging below or sliding past plates, etc., makes a strong case for the validity of the general theory. However many details have yet to be explained. In fact, modifications of the theory have been rapid. No doubt more revisions can be expected in the future. The driving force that moves the plates is still debated. Nevertheless the main features are likely valid.
    Contorted or overturned strata in mountain ranges and deep basins filled with fossiliferous sediments were evidences that pushed creationists to view the Genesis flood as a major event. Now the evidence concerning moving plates has forced us to enlarge even further our concepts of the global extent and catastrophic dynamics of this event.
    If major earth plates have moved to create the modern pattern of oceans and land masses, when would this movement have occurred? Creationists notice that Paleozoic sediments are absent from the ocean basins. These sediments are among those considered to have been deposited by the Genesis flood. This observation suggests that the separation of the continents (when the Atlantic Ocean, for instance, was created) commenced in the latter stages of the flood or in early post-flood time.
    In summary: creationists familiar with the evidences generally accept the idea of moving plates but place the main activity during the last stages of the flood and early post-flood time. Obviously they also postulate high rates of plate movements. Perhaps the present movement (said to be 2-3 cm/yr) represents a residual of much more rapid motion that commenced a few thousand years ago as flood waters began to recede. Such rapid movements of plates is not without its own problems. The relationship of plate tectonics to the Genesis flood is a subject that needs more study.

GEOSCIENCE NEWS

AT THE GC SESSION

    During the July session of the General Conference of Seventh-day Adventists (including the Ministerial Department Pre-session meetings) which convened in Indianapolis, the Geoscience Research Institute conducted two Science and Religion Seminars and maintained a booth in the exhibit hall. In addition, Dr. Ariel Roth, the director of the Institute, spoke in a morning devotional to assembled delegates and visitors.
    About 800 individuals attended the two Science and Religion seminars, each of which ran for four hours. The Geoscience Research Institute staff reported on recent developments, their research, and on issues of concern to the world church.
    Several thousand copies of a Geoscience brochure, Origins, Geoscience Reports, and Ciencia de los Origenes were distributed at the booth. Many visitors stopped to ask questions, to watch the continuous run of the Flood video, and to examine the dinosaur footprint and fossils on display. Interest in the relationship of science to Scripture appeared to be high.

GEOSCIENCE RESEARCH

    During the summer Clyde Webster and Harold Coffin spent two weeks in the Yellowstone region collecting samples of volcanic ash. It is hoped that these samples will give some information regarding the source areas of the ash and breccia layers in which the petrified trees of Specimen Creek are buried. Collecting the ash samples required the climbing of several 10,000 foot peaks and much hiking (including one hike of 20 miles). A previously unknown fossil forest was discovered, the full significance of which has yet to be determined.
    From Yellowstone, Coffin went on to Central Oregon to examine and collect specimens of fossil Equisetum (horsetail plants) and to study the paleoecology of these Eocene fossils.
    In the months of August and October Ben Clausen spent a total of six weeks doing research at the Los Alamos National Laboratory in New Mexico. The purpose was to develop some features of the nuclear shell model. In this model, protons and neutrons orbit in shells in the nucleus just as electrons orbit in shells in the atom. One experiment studied ²⁶Mg and ³²S nuclei by hitting them with pions and then detecting the energy and angle at which the pions were scattered. These pions, with half-life of less than a microsecond, are the particles that hold the nucleus together. The other experiment involved hitting a ¹⁰B nucleus with a neutron to make ¹⁰Be plus a proton whose energy and scattering angle were measured. This reaction is comparable to the inverse of beta decay. The data from these experiments are currently being analyzed.

BOOK REVIEW

Peth, Howard. 1990. Blind Faith: Evolution Exposed. Amazing Facts, Inc. P. O. Box 680, Frederick, MD 21701. 188 pp.

    Howard Peth, a Seventh-day Adventist professor in a public college, has often faced the problem of secular humanism so prevalent on university campuses. The need for written materials to assist students without any foundation in Christianity or Scripture led him to write a two volume work entitled Seven Mysteries ... Solved. From these volumes, Blind Faith: Evolution Exposed has been extracted and adapted, with the subject being limited to the evolution/creation issue.
    Although Peth is not a scientist, he has handled the question of evolution/creation carefully and as thoroughly as the size of the volume permits. Quotations from the writings of past and current evolutionary theorists are liberally sprinkled through the volume. Peth has limited himself almost entirely to a discussion of the theory of evolution and to the problems a belief in this theory holds for those who accept the Bible as the inspired Word of God. Little attention is given to evidences of a world-wide flood or to geological time and dating methods. Considering its main purpose, to acquaint secular individuals with the fallacies of evolution and to do so in one concise handy booklet, the decision to limit the discussion to the question of origins was wise. The book concludes with a unique and important discussion of theological implications of a belief in evolution.
    In general the presentation is remarkably accurate and authoritative. One short section (pp. 111 to 116) in the chapter on paleontology does not maintain the quality of the rest of the book. Arguments concerning the geological column reflect some of the erroneous information that is commonly found creationist writings. With the exception of these few pages, the few minor errors and statements that need qualification will not seriously detract from the value of the work.
    This booklet would be excellent additional reading to accompany a high school or college freshman biology course. It would be an appropriate gift for a friend who has questions about creation and evolution. It would be good reading for anyone who wants to review again the weakness of the evolutionary theory and the incompatibility of belief in evolution with biblical Christianity.

GEOSCIENCE REPORTS
Fall 1990 No. 12

Editor Harold G. Coffin
Associate Editor Katherine Ching

Subscription requests, correspondence, and notices of change of address should be sent to: Geoscience Reports, Geoscience Research Institute, Loma Linda University, Loma Linda, CA 92350.

Geoscience Reports is a newsletter published by the Geoscience Research Institute to present current happenings at the Institute as well as articles of general interest which deal with creation/evolution issues for secondary school and college science classes. The views expressed are those of the authors and not necessarily those of the Institute.

Staff of the Institute are Ariel A. Roth - Director, Katherine Ching, Ben L. Clausen, Harold G. Coffin, L. Jim Gibson, and Clyde L. Webster.