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p.1 • Catastrophes and Earth History
• Leonard Brand
p.4 • Editorial
p.5 • Science News - Biology, Geology, Paleontology, Dino Notes
p.6 • GRI News
p.8 • Paleobiology of Dinosaurs • M. Elaine Kennedy
EDITORIAL
The feature article in this issue
was contributed by Dr. Leonard
Brand, Chairman of the Department
of Natural Sciences at Loma Linda
University. The article was originally
published in the department's
newsletter, "Earth History News." He
was kind enough to allow us to
republish it for the benefit of
secondary-level science teachers and
their students.
While the acceptance and
recognition of catastrophic events in
the geologic record represents a major
shift in the thinking of geologists, there
is no indication that scientists are
willing to consider the validity of a
worldwide catastrophe such as the
Noachian flood (see Brand's
comments on Bretz, this issue). Allen
and Bums, in their book Cataclysms
on the Columbia (Timber Press, 1986),
state, "Bretz's opponents saw only
what they had resolved to see. They
were prime examples of the geologic
quip, 'I wouldn't have seen it, if I
hadn't believed it.' Like members of a
faith whose existence is threatened
when one small variant is thrown into
the system, so these men seemed to
feel the entire discipline of geology,
and all it stood for, would be sent
crashing if Bretzs reintrepretation of
catastrophism. were given serious
consideration. " Attitudes toward
creationi d flood geology seem little
changed from Bretzs day. However,
the geologic record of Catastrophes is
consistent with the biblical account of
a very complex, worldwide flood, with
an aftermath extending well beyond
the flood year.
We want to thank Dr. Brand for
his willingness to contribute to
Geoscience Reports.
SCIENCE NEWS
BIOLOGY
Jablonka, E., M. Lachmann and M. J. Lamb. 1992. Evidence, mechanisms and models for the inheritance of acquired characters. Journal of Theoretical Biology 158:245-268.
Proper gene action requires some
method for turning the gene on or off
at the appropriate time. One way in
which this is done is by modifying the
DNA by adding or removing a methyl
group (CH3) to cytosine nucleotides.
Addition of the methyl group is thought
to turn the gene off, while its removal
activates the gene. When the DNA is
copied during cell reproduction, the
methylation state is also normally
copied. Thus a gene that is active (or
inactive) in a parent cell may also be
active (or inactive) in the daughter
cell. If the cell is a reproductive cell,
the offspring may inherit the gene
activation state of its parent.
The idea that acquired
characteristics can be inherited was
popularized by Lamarck in the early
19th century. However, the idea was
rejected when the principles of
genetics were discovered. Now it
appears that there might be some
cases in which environmental
influences might affect heredity. Some
genes respond to environmental
conditions, resulting in addition or
removal of methyl groups from the
DNA. The resulting change in gene
activity may appear to be a mutation,
although it is actually only a change in
gene activation state. Because the
state of DNA methylation can be
inherited, the change in gene activity
may also be inherited. Thus, an
environmentally stimulated genetic
change can be inherited. This process
has been called "epimutation."
Epimutations are thought to be more
common than changes in DNA
sequences. This phenomenon can
make it difficult to be certain whether
an observed genetic change is due to a
mutation or an epimutation. It also
suggests that some acquired
characteristics may be inherited,
although not in the way proposed by
Lamarck.
GEOLOGY
Hanson, Bernold M. 1993. What happened to science? American Association of Petroleum Geologists Bulletin 77:1573.
Quote from the abstract: "Basic mineralogy would have told us that 95% of asbestos fibers are harmless and would have saved taxpayers millions of dollars in the so-called cleanup.... release of chlorine from the sea and volcanoes dwarfs the chlorine released by CFCs.... harmful radiation is not increasing.... air polluting materials produced by man since the beginning of the industrial revolution do not begin to equal the quantities of, toxic materials, aerosols, and particulates spewed into the atmosphere by the volcanoes.... sundry animals and insects also contribute huge amounts of carbon dioxide.... no evidence of widespread forest damage from current levels of acidic rains in the US.... acidity of the soil, not precipitation, determines the acidity in watersheds." Hanson's abstract expresses concern over government regulation based on premature scientific conclusions.
PALEONTOLOGY
Greben, Rebecca and Martin G. Lockley 1993. The Mesozoic and Cenozoic bird track record. a bus in favor of shorebirds Journal of Vertebrate Paleontology (Supplement Abstract) 13:38-39A.
There are approximately 100 bird trackways known worldwide. About half of those sites are found in Cretaceous deposits, and the other half occur in Cenozoic rocks. Less than 10% of the trackways contains impressions of webbed feet with some occurring in Cretaceous deposits. Duck-like tracks in Eocene through Pliocene rocks also have "dabble marks" (feeding traces). The waterfowl trackways occur in deposits that have been interpreted as shorelines or lake sediments. [Trackway preservation requires rapid sedimentation and cementation. Ed.] The tracksite record is strongly biased in favor of shorebirds and waterfowl. Trackways for grounddwelling birds, perching birds and birds of prey (raptors) are in some cases non-existent.
Hunt, Robert M., Jr., R. I. Skolnick and E. Stepleton. 1993. Denning behavior of large mammalian carnivorans. Oldest burruws found in the earliest Miocene (22 Ma) of North America. Journal of Vertebrate Paleontology (Supplement Abstract) 13:42-43A.
Two sites in northwest Nebraska have been interpreted as den complexes. The filled burrows contained bones. The site at Beardog Hill (Miocene) contained 2 species of amphicyonid (an extinct dog-like animal the size of a bear with a long, massive tail; short, powerful limbs; spreading, five-toed feet; and tooth structure indicating they were omnivores), 2 species of mustelid (weasel), a small, unspecified canid (dog-like), plus probable prey: juvenile oreodont (pig-like appearance with ruminant or "cud-chewing" tooth structure) and rhinoceros. From the site near Agate National Monument, bones of a wolf-sized amphicyonid, an unspecified rodent and a small fox-like carnivoran have been found in burrows. Den sites are difficult to establish in the fossil record.
DINO NOTES
Carpenter, K. and B. Small. 1993. New evidence for plate arrangement in Stegosaurus steno (Dinosauria). journal of Vertebrate Paleontology, Abstracts 13(3):28A.
Researchers report the second "road-kill" specimen of a stegosaur has been found about 1.25 km from where the first specimen that was found in 1886. Nearly all the plates along the back were found in place, and the plate arrangement was alternating rather than formed in double rows. The plates along the back may have restricted movement. The neck and end of the tail section had the greatest degree of movement.
Larson, P. L. 1993. Sexual dimorphism in dinosaurs and their relatives. Journal of Vertebrate Paleontology, Abstracts 13(3):46A. Also see: Fischman, J. 1993. To sex a T. rex. Science 262:846.
Larson compared the tail structures of 14 T. rex specimens to crocodiles, ratites and ducks. The first chevron under the tail of the female crocodile is farther away from the pelvis and smaller in size than that of the male. Similar features were found on the T. rex skeletons. An overall comparison of skeleton size revealed that the 'males' are consistently smaller than the 'females.' According to Sankar Chatterjee (Texas Tech University), "In many modern reptiles, and in birds of prey, the female is larger than the male."
GRI NEWS
Drs. Ben Clausen and Clyde Webster
traveled to our Seventh-day Adventist
seminaries in Europe for 5 weeks in
November and December, 1993. This is the
first time GRI staff members have lectured
at any of the seminaries in East Europe
other than Friedensau. Adalbert Orban,
Principal of the Romanian Theological
Seminary in Bucharest, described their
coming "as refreshing as cool water in a
hot desert." Dr. Webster characterized the
general level of scientific background of
the faculty and students as high, with
comments and questions that were
insightful and meaningful. The men
enjoyed a firsthand geography lesson
when they spent a week in Prague (capital
of the Czech Republic) and the weekend in
Bratislava (capital of Slovakia). In
Bratislava they met with SDA students
and other university students from the
area, as well as some non-SDA professors.
After the meeting, these professors gave
their business cards to the presiding elder
and asked to be contacted if GRI ever
returned to their country. We are
encouraged by their desire to continue
dialogue on the creation issue.
In late November Dr. Jim Gibson
traveled to Helderberg College in South
Africa for a Faith and Learning Seminar.
He gave four lectures on the interface
between creation, science, biology and
the Christian faith.
In early December Dr. Elaine Kennedy
gave two workshops at the Annual
Ministerial Conference at Oakwood
College. The pastors have been concerned
about the impact of evolutionary theories
taught to their youth attending public
schools.
PALEOBIOLOGY OF DINOSAURS
M. Elaine Kennedy, Geoscience Research Institute
"Her first thought was that the
dinosaur was extraordinarily beautiful.
Books portrayed them as oversize,
dumpy creatures, but this long-necked
animal had a gracefulness, almost a
dignity, about its movements. And it
was quick — there was nothing
lumbering or dull in its behavior. The
sauropod peered alertly at them, and
made a low trumpeting sound rather
like an elephant."1
In recent years paleontologists
have witnessed a revolution in their
interpretations of the paleobiology of
dinosaurs. The fossil record has
provided new insight into possible
dinosaur behaviors. These
interpretations are based on a variety
of data.
The data can be loosely grouped
into 7 categories: 1) Bones: fragments,
isolated bones, and articulated
skeletons; 2) Skulls and teeth; 3) Skin
impressions, scales, scutes and spines;
4) Stomach contents, dung, and
gastroliths; 5) Eggs, embryos, nests,
hatchlings, juveniles; 6) Trackways; 7)
Death assemblages: Much information
can be gathered from the fossil
material and from the entombing
sediments.
Behavioral implications are then
postulated based on the data collected.
For example, an examination of the
Hypsilophodon tail reveals bony
structures that restricted tail
movement and caused the tail to
remain rigid. It has been suggested
that the stiff tail was used to maintain
balance or as a
"dynamic stabilizer" enabling the
dinosaur to make sudden turns while
evading a predator.2 Areas of muscle
attachment on the bones aid in the
reconstruction of the animals and
provide rough estimates of probable
strength and body mass.
Several behavioral interpretations
have been based on the skulls of
dinosaurs. The ratio of the cranial
capacity to body size is used to
estimate intelligence. The ratios are
compared to various reptiles, mammals
and birds.3 Using this method, it has
been postulated that velociraptors had
the intelligence of a chicken. In
addition to the information available in
regard to size and position of ears,
eyes and nose on a skull, endocranial
casts are examined to determine the
sensory abilities.4 The teeth and jaws
of the skull provide information about
possible diet. For herbivores,
associated plant material is also
considered (although evidence of an
adequate food supply for the very
large herbivores is lacking.)5 Additional
data that may contribute to our
understanding of the dietary habits of
dinosaurs would include "petrified
stomach contents," gastroliths or
gizzard stones and dung.
Unfortunately, such materials are
difficult to identify accurately. Recent research6 on some isolated clumps in
the Two Medicine Formation in
Montana, USA, has reported probable
dinosaur dung. The deposits consist of
conifer xylem that has been burrowed
by dung beetles. The coprolites were
located near hadrosaur bones and
nests.
Skin impressions have been ascribed
to 48 genera.7 Several hadrosaur skin
impressions have been found, and careful
examination of these skin impressions
suggests that the neck was thicker and
more muscular than the gooseneck
previously proposed for the hadrosaur. In
addition, the ruffled frill is probably skin
from the side of the neck rather than
dermal spines typical of true frills (bony
neck protection).8
Dinosaur eggs have been known from
Mongolia since 1922. The most complete
information regarding dinosaur eggs and
nests has come from the excavations in
Montana, USA. CAT scans have been
used to identify dinosaur embryos in
eggs. Eggs have been found that
contained babies only partially hatched.
Bowl-shaped depressions have been
found with eggs arranged point down in a
spiral pattern. Juveniles with worn teeth
have been found in nests with broken
eggshell. Several varieties of dinosaur
eggs and nests have been discovered.
From the database for the maiasaur
nesting sites in Montana, it has been
postulated that 1) as many as 40 adults
laid eggs at the same time and at the same
site, 2) the young remained at the nest site
and 3) adults stayed in the area to care for
the young, behavior that is typical of
warmblooded animals.9
Trackways are used to interpret gait,
speed, paleoecology and habitats of
dinosaurs. Spacing and arrangement of
the tracks determines gait. Theoretically,
the quadrupeds and large bipeds preferred
walking. Some trackways of smaller bipeds
have been interpreted as running or
hopping tracks. Parallel tracks are
interpreted as herding behavior and migration.10 Such an interpretation
assumes that the trackways represent
normal behavior. Stress introduced by
some catastrophic event
would produce a very different
interpretation for the tracksites.
Trackways are found in a wide variety of
deposits. The deposits have been
interpreted as a wide variety of
paleoenvironments: flood plains; streams,
soils, and playa lakes in and regions;
deltas and coastal plains.11 The identity of
the dinosaurs responsible for the tracks is
difficult to ascertain. Track size may vary,
and the interpretation of the tracks as
those of an adult or juvenile may be
unreliable.12
Important information is also
gathered from death assemblages. When
researchers are looking at an extensive
deposit of maiasaur bones,13 a
velociraptor gripping the head of a
protoceratops or an articulated skeleton
with contorted neck and tail bones,14 the
bone condition and sediments in which
the bones were deposited are studied to
determine the mode of death, burial and
subsequent preservation processes.
Multiple lines of evidence have been
used to address the possibility that
dinosaurs may have been warm-blooded.
Their large chest cavities and "migratory"
behavior have been cited as evidence for
endothermic systems.15 Additional
evidence for warm-bloodedness comes
from research by Barrick and Showers.16
They compared oxygen isotope ratios
from the bones of seven dinosaur species
to the ratios in bones of a deer, cow and
the cold-blooded Komodo dragon. The
tail of the Komodo dragon ranged from 4°- 16° colder than its ribs; whereas the
mammals had less than 7° difference
between the legs and ribs. According to
Barrick and Showers the dinosaur ratios
fell within the mammal range.
Despite the broad range of data
available, there is much to be learned
about dinosaurs and their behavior.
Paleobiological interpretations will change
as new discoveries are made. It is
important to remember that many of the
questions that need to be addressed
from the perspective of those who accept
a biblical explanation for earth's history
are not being asked by the secular
geologic community.
Endnotes
GEOSCIENCE REPORTS
Winter 1994 No.17
Editor - M. Elaine Kennedy
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 USA Annual subscription rate is $3.00 (U.S. currency).
Geoscience Reports is a newsletter published by the Geoscience Research Institute to present current happenings at the Institute as well as general-interest articles that deal with creation/evolution issues for elementary/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: Ariel A. Roth, Director (Ph.D., zoology); Ben L. Clausen (Ph.D., nuclear physics); L. Jim Gibson (Ph.D., biology); M. Elaine Kennedy (Ph.D., geology); Clyde L. Webster, (Ph.D., chemistry); Katherine Ching, Editor (M.A., history); and Janet Williams, Administrative Secretary.
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