Chapter Highlights from Creation and Evolution: Myth or Reality?
Norman D. Newell (1985)
Evolutionary Biology BI 25, Saint Anselm College
Chapter 1 Patterns of Life
Complexities of ecology and ecosystems
diversity of species and relationships between organims
food webs, predator/prey and symbiotic relationships between organsims
Paleontology - link between geology and biology, provide a meeting place for understanding origins of life
Points of View - differences between belief system of Religion and investigative system of science = source of conflict
Chapter 2 Trouble in Eden
1896 - It's (controversy of Evoltion versus Creation) all over according to A. D. White
WRONG - series of ongoing battles in the 20th century
1925 - Scopes Monkey Trial - Scopes is the schoolteacher who taught evolution against Tennessee law and was found guilty, W. J Bryan (Creationist lawyer) versus C. Darrow (Civil rights and Scopes' lawyer), law later declared unconstitutional by the US Supreme Court
1922 - 1929, legislation banning teaching of evolution introduced in 37 states, 3 were passed and later declared unconstitutional by federal courts
1960's - 25 states introduced measures again to ban teaching evolution by state legilatures
1963 - formation of the Creation Research Society
Subsequent development of more creation science societies, institutes, publishers, etc.
These creation science societies have published their own biology texts that lack treatment of evolution, also publish instructions for science teachers on how to teach the creationism in public schools without reference to religion
Creationism is not science! does not adhere to scientific principles or the use of the scientific method, all hypotheses are falsifiable,
Creationists point out that the scientific community is split over evolution - Newell points out that this is incorrect and taken out of context
Creationists and the fundamental interpretation of the Bible - strict literal interpretation, creationists can not tolerate disagreements with any of the Bible's writings, teachings, principles, etc...
Causes of the controversy - public misconceptions, mistrust and confusion over science: quick to blame science for society's problems, warfare technology, scientists are atheists and antipreligion
Catholic Church's stand on Evolution
Pope John Paul II's Message to Pontifical Academy of Sciences on October 22, 1996
Christus Rex Information Service reports on Pope John Paul II's message
The Cutting Edge reports on John Paul II's message
Chapter 3 Fantasy and Reality
Scientific literacy, lacking in most people, susceptibility to the mysterious and sensational
Evidence - fascination with the occult, astrology, sensational stories - Bermuda triangle, UFOs, beleif in magic, miracles, etc...
Science (construct hypotheses and test them with evidence) versus pseudoscience (draw a conclusion and find the evidence for it)
Examples of pseudoscience
Velikovsky's ideas on the earth's history
Aboriginal tribes - think plants have the faculty of awareness (e.g, to grow upwards)
Chapter 4 Noah's flood and other catastrophes
Catastrophes interpreted as evidence of God's will before era of modern science
Legal terminology - Act of God
Catastrophism - idea used to explain extinctions
Modern geology - much better understanding of the recurring nature of violent geologic processes
Noah's Ark and the flood
clam fossils in the mountains was considered evidence of the flood
Burnet - calculated the amount of rain needed and concluded that it rained and the water ended up in large caverns in the earth - these have never been found, US Geological Society calculated the amount of water in the atmoshpere and the ice caps - could not have covered the entire earth, no geological evidence of a universal ocean
Da Vinci seriously questioned the idea of the great flood responsible for depositing clams in mountains, concluded that the mountains were once in the valleys and had been uplifted over time
Great floods of the past - no floods completely covered large parts of the earth
Evolution of landscapes
Canyons around the world reveal sedimentation and layering - organisms were layered in strata of different ages, different organisms in different layers at different time zones - does not support the idea of the flood that all organisms lived together at the same time
Sedimentation - reveals the old age of the earth, takes millions of years for sediments to accumulate on top of each other, canyons on land and in the depths of the ocean have very slow accumulation/sedimentation rates
Chapter 5 Clues to the past
The Dawn of Science
1500's - Copernicus (astronomer) and Vesalius (human anatomist describes human anatomy in great deal)
1600s and 1700s - Bacon, Descartes and Newton search for natural explanations of natural phenomena (not intuition, revelation or miracles)
Geological laws
Steno - law of super-position (older rocks below and younger rocks above), law of horizontality (sdeiments tend to be flat so all rocks at the same level are about the same age)
18th Century - religious orthodoxy and return of creationism after the French Revolution
Buffon - publishes general knowledge of the earth, estimates age of the earth at 74,000 years old, later forced by conservative theologians to recant his ideas
1788 - Hutton publishes History of the Earth, present is key to the past, could age rocks by their degree of wear and fragmentation, most worn and fragmented were the oldest, process of wearing down rocks takes millions of years, extends estimates of the age of the earth
1800's - Lyell examined rocks from the past and concluded that whatever happened in the past was very similar to what we observe in the present
Whewell - coined the term uniformitarianism, to describe Lyell's idea
Sampling the past - similar to detective work, collect and evaluate evidence, try to find the story
Science and the search for the truth
abusing the term theory - unsupported speculation
correct use - theory is an explanation buttressed by verifiable facts, always subject to testing and falsification
Creationism does not lend itself to testing with evidence, based on a belief system
Chapter 6 Fossil Elephants show the way
10th and 11th centuries - Arabs develop caravan routes to Siberia and an ivory trade, but there were no elephants, tusks were dug from permafrost
Cuvier, Camper and Blumenbach conclude that the tusks are from mammoths, close relatives of two living species of elephants, the mammoths had to be extinct because their bones did not resemble those of any living species
Fossils - remains or traces of ancient animals in rocks or soil
Proboscidea contains modern species and fossil relatives of the elephants were among the first species to receive widespread attention, incredibly diverse group, large animals with great fossil record
Mammoths - more recently evolved, two massive molars above and below, only upper tusks
Mastodons - oldest members of the group, several low-crowned cheek teeth, lower and upper tusks
1977 - completely frozen Wooly Mammoth found in Siberia
What caused the demise of the mammoths - Farrand says that gradual climatic change was responsible
Evolution of the Proboscidea
ancestors - small pig-like ancestors, similar to tapirs
relatively recently evolved, found in most recent strata - shallow swamp and stream sediments
Value of elephant fossils
1) fossils are evidence of extinct life from the past
2) fossils are often found by erosion of rock that reveals strata
3) fossils and their rocks reveal clues about the environment in which they lived, often different from current conditions
4) Most fossils belong to extinct species, very few (less than 1%) belong to species that are still alive but have gone locally extinct
5) Most species are relatively short-lived, appear and disappear quickly in strata, rock, sediments and the fossil record
Chapter 7 Treasures from the past
Origin of fossils
Most body parts are destroyed by bacteria or other saprophytic organisms, minerals and chemicals are recycled
Also are physically destroyed by sedimentation or other natural forces
Fossils are organisms or their parts that have escaped destruction and are in the right place at the right time
Bias - fossil most organisms are ones that lived near or in aquatic environments, can be easily buried by sedimentation
Kinds of sedimentation
mineralization - minerals replace organic parts of dead organisms, fill in the pores
bog preservation - aseptic conditions
silification - silica enters into and preserves organisms (petrified wood)
Abundance of fossils - some fossil locations are incredibly rich in fossil species
Problems - amateur and private collectors, cause damage and collect valuable specimens lost to the scientific community for study
Chapter 8 The fossil calendar
The sequence of fossils in geological time
Smith - civil engineer who realized that rocks were organized in strata on a time scale with the most recent rocks on top and oldest rocks on the bottom, clue was fossils that appeared in the same strata but at different locations, could be used to age rocks and arrange in chronological order
Smith worked for mining industry, observed that rock formations occurred, they varied in thickness, and their relative sequence remained in tact from place to place
Counter to creationists view of arrangement of organisms from simple to complex, with the more complex on top and simple on bottom, due to the scrambling by more complex organisms to mountains to escape the flood
Sequence of fossils
international geological time scale established in the 1840's
Zonation
distinct assemblages of species, genera, etc...
Geological time scale
Eras from youngest to oldest
Cenozoic
Mesozoic
Paleozoic
Lyell and Deshayes
Lyell
studied fossils in Sicily and France, synthesized information about time scale into a universal system
Deshayes
developed mathematical relationship between stratigraphic position of fossil marine organisms and and their relationship to recent, living marine species
devise the Epochs of the Cenozoic based on their studies of marine fossils (missing Oligocene that came later)
Recent
Pleistocence
Pliocene
Miocene
Eocene
D'Orbigny
subdivided older eras
Pre-Darwinian Paleontology
general consensus on the arrangement of the fossil record but no evolutionary connections
1) distinct assemblages of species are characteristic of different strata
2) differences between assemblages increase with age
3) alternating assemblages of terrestrial and marine organisms (represents regular movement and coverage of land by the ocean)
World mapping
drilling on land and in the ocean - provided new units of measurement of stratigraphic sequences and depth of sequences
Chapter 9 The geological clock
Theological time
St. Augustine estimated 6,000 years based on biblical genealogies
Bishop Usher - 4004 BC was year of creation
John Lightfoot - supported Usher and went further to have the exact date and time: September 17, 4004 BC at 9:00
Modern creationists - 10,000 years old
Modern science - 4.5 billion years
Absolute time
geochronoligical time - based on various methods of dating, given in years B. P. (before present)
Properties of atoms
atoms vibrate at known rates because of the dependable movement of electrons between shells
Atomic clocks
1972 - atomic clocks run at a constant rate, regardless length of day or ration of earth around the sun
Radioactivity
decay of radioactive substance - 1/2 life
Radiometric dating of rocks
Boltwood - uranium breaks down into lead, found that more lead compared to uranium was found in older rocks
Age of the earth
Holmes - used uranium isotopes and lead method to estimate that the earth was about 4.5 billion years old
Confirmed by independent methods (aging old meteors, moon rocks) no rocks on earth this old, oldest earth rocks from Greendland are 3.8 billion years old, 4.6 billion years is still assumed to be approximate age of formation of the earth
Radiocarbon
C12 and C14 (isotope) ratios
Paleomagnetic Scale
variation in the earth's magnetic field, fields move westward on a regular basis, revolve around the axial poles once/10,000 years, iron particles in rocks are like frozen compass needles which can be used to age rocks
Oxygen Isotope Method
evidene from glacial and interglacial periods in the earth's history, based on Oxygen 18 (O18), O18/O16 ratio is higher in sea water than in fresh water, increases with temperature and salinity, picked up by aquatic invertebrates living in sea or freshwater, glacial and interglacial periods are recorded in the oxygen ratios in these invertebrates,
Varves
summer versus winter sediments in lakes and ponds, leave light (summer) and dark (winter) layers, similar stratification in ocean sediments, caused by plankton blooms, similar banding patterns in ice and glaciers
Coral
tides acts as brakes to the roation of the earth, slowing down its rotation, can be picked up in the annual growth bands of corals, each growth band represents one year and is composed of growth lines of equivalent to one day, Wells found that the number of growth lines per year was decreasing in fossil coral, older coral had more growth lines, younger coral had fewer lines
Chapter 10 Diversity and classification
Life on earth is diverse, from bacteria to whales, maybe as high as 10 million species
Number of species has tended to increase over time as shown by the fossil record (in contrast to Creationist assertions that diversity is declining due to extinction)
Marine origin of life
Regional differences in diversity
Buffon - biogeography studies revealed interesting patterns in diversity and distribution of animals
Areas with unique floras and faunas: Hawaii, New Zealand, Australia, Madagascar
Darwin - each area's unique biota is the result of isolation and subsequent origin new species and higher taxa
Local differences
organisms are limited to their present distributions at the ecological level as well as the biogeographical, constrained by ecological conditions and requirements
Tropical Splendor
most diverse areas are in the tropics
Naming organisms
Linnaeus - devised the hierarchy, latin names and binomial epithet - standard for all species
Species are natural populations
species are groups of populations that are reproductively isolated from other such groups, can be distinguished by phenotypic differences which have a genetic basis
modern classifications reflect the relationships of species to each via the recency of a common ancestor through evolution
Chapter 11 Heredity and Evolution
Chemistry - evidence of evolution
all living things share very similar chemical compositions: C, O, N, H, S
Basic unit of life
cell - for unicellular and multicellular organisms, place of biochemical activity
types - prokaryotes and eukaryotes
organelles of eukaryotes - may have arisen from prokaryotes living inside other prokaryotes (endosymbiont theory)
Genetic machinery
prior to Mendel - blending inheritance (blood from one parents blends with the blood from another, this is where we probably got the term - bloodlines)
Mendel and Mendel's laws provide the framework of the discipline of genetics
Morgan - identifies the chromosomes as the region where the genes reside
Origin of sex cells
meiosis - formation of the gametes (random assortment of genes into sperm or eggs)
crossing over maintains genetic variation
recombination during meiosis maintains genetic variation
2n - number of possible combinations of alleles
Mutations
may occur at the chromosome or gene level
positive benefits - safeguard against extinction by maintaining variability in a population
negatives - often lead to death of the organism
rate of mutation is relatively constant
Chemical basis of heredity
Watson and Crick (1953) - discovery of the structure of DNA
gene - sequence of nitrogenous bases
Universal genetic code
DNA, RNA, nitrogenous bases found in all living organisms
Classes of genes
structural genes - produce proteins that are involved in chemical reactions that produce the structures in the body
regulatory genes - regulate growth during development
transposons - jumping genes
transcription and translation - from gene to protein
Neutral genes
no adaptive value
Molecular genealogies
use of biochemical genetics to classify organisms -compare DNA or products of DNA (proteins) among species, closely related species will have more similar DNA than distantly related species
Chapter 12 Adaptation: a question of design
Divine Purpose
Questions about adaptation - form and function
Ray (17th ) and Paley (19th) wrote about creation and design, so organisms were perfectly adapted to their environment
Beauty is in the eye of the Beholder
Darwin - purpose of form was really for a biological function, example - flower color and odor to attract pollinators for fertilization, Venus fly trap species for predation on insects and small frogs
Are organisms perfectly adapated to their environment - NO!
Many examples of flaws
process of aging and death
genetic mutations
neutral characters with no benefits
Urge to Evolve
Lamarck was one of many who introduced the idea of change but he thought it was due to an inner urge to react to different environmental conditions, change was directed towards perfection
Problem - how can organisms predict their future needs and evolve towards them - no evidence for this
Awesome potential of birth rates
Linneaeus and Malthus - described the potential growth rates of populations
Darwin - realized that there were natural means of governing population growth
limited resources could impose selective pressures on populations and reduce growth rates
An idea is born
Darwin describes process of natural selection - survival of the fittest individuals
Stimulated to publish his results after receiving correspondence on the subject by Wallace
Famous presentation in 1858 at the Linneaen Society Meeting by both authors
Artificial Selection
evidence of possibilities of selection
natural selection takes much longer because it is less intense and not controlled, subject to random processes in the environment
most cases of released domesticated animals result in death or breeding back with conspecifics and loss of the artifically selected characteristics
Environmental Tolerance
Homeostasis
creationists argue that it is an example of supreme creation and that nature takes care of its own by divine design
biologists argue that biochemical processes occur within strict limits in organisms, regulated by proteins that workin within limits enforced by environmental conditions, organisms moved out of their normal environments die because of the inability of proteins and internal biochemistry to handle new or different conditions, what works in one environment fails in others
Environmental niches
where and how and animal lives in its environment, unique to each species,
example - animals on the Serengetti Plains, ungulates divide up the plant species, occupy different food niches, different species may exploit the same food niches but a different times of the year to avoid competition
example - scavenging birds of Africa, arrive at different times after a kill to feed on a carcass
Competition
overlap in resources among species can result in competition, in turn results in conflict, usually not direct violence but a performance competition, example - low numbers of migratory landbird species in the tropics where there are high numbers of resident species, the latter have already divided up the available resources and occupied those niches, reducing the available to niches
Objection to Natural Selection
problems with social Darwinism
problems with natural selection acting as a sieve, producing nothing new, just acting as a filter for what already exists
problem - based on circular arguments, natural selection is not real and therefore evolution has no mechanism
biologists counter that natural selection actually favors novel genetic recombinations in different environments and may eliminate them in others, only works in special situations under special conditions
Chapter 13 Structure, growth and form
Anatomical similarities
Methods and results from the Comparative Anatomy revealed a wealth of information on the structural similarities that exist among organisms at various levels
Example - cats belong to the Felidae, family of carnivorous mammals, all members are similar anatomically, differ at the species level in shape, size, proportion, coloration, etc.; differ from other mammals (like Deer) but still share some characteristics with them
Cuvier - published classification of animals based on anatomical similarities, each group has a basic structure (bones and arrangement of bones) that is a "plan" for that group, other member species of the group share the same body plan, Cuvier pointed out how a few bones from one organism could be used to reconstruct the entire organism based on principles of form and function from many previously known species
Homology - organisms possess similar structures because they shared a common ancestor which also had these structures
Example - forelimb of vertebrates
Convergent evolution - similar adaptations evolved in distant related species
Examples - wings of flying animals or Australian Marsupial mammals
The building of an organism
Development - process of an egg becoming an adult
Aristotle - discovered the importance of "sequence" - each subsequent stage of development is based on the stage preceding it
Recognition Molecules
Molecular structure of cells (e. g., cell membrane) is recognized by cells and cells with similar molecules are attracted to each other
Example - 1) zoology course exercise of pushing a sponge through wire mesh, eventually the cells recognize each other and get back together again, 2) cells of the immune system, imunnological distances (cells of species A come into contact with species B, species A develops immune response and antibodies to species B and relatives of species B, we can use species A's reaction to other species to elucidate phylogenetic relationships among organisms)
Individual Growth and Development
Use of fruit flies reveals that growth of body parts is under control of regulatory genes, regulatory genes control growth of different body compartments
Darwin - also mentioned the effects of the environment on growth, realized that the environment could maintain anatomical differences among organisms - tanning, use/disuse of muscles, seasonal changes in leaf color of trees, etc...
Cell Sequences
Process of development:
Vertebrates: zygote - blastula - gastrula - neurula
Some Invertebrates: various larval stages
Vestigial Organs
Definition - organs that have lost their original or ancestral function
Examples: vertebrate development (e. g., - gill slits, other), primitive birds that don't fly but still have wings (Ostrich, Penguins. other), snake with a pelvis, baleen whales with teeth in early stages of development
Embryonic Resemblances
von Baer sees that developmental stages of many vertebrates are very similar
von Haeckel - thought that each stage of development was one species going though a preceding stage equivalent to its ancestors - ontogeny recapitulates phylogeny
Today we know that the similarities in development are due to the close relationships between organisms and their ancestors - similarities are due to recency of common ancestry
Old organs with new functions
modifications of organs in ancestors are the results of minor changes in developmental body plans, new structures do not appear, they are the result of modifications of pre-existing structures
Relationships stem from common ancestry
biochemical, morphological, behavioral, developmental similarities among organisms are not mere resemblances of divine creation, they are due to common ancestry, shared characteristics with a common ancestor
Chapter 14 The origin of species
2 Levels of Evolution
Microevolution - studies of evolution over the past few generations
Macroevolution - studies of evolution over long periods of time
Microevolution
Observing evolution - humans and disease, pests and agriculture, pepper moths, European House Sparrow in North America and other examples of introduced species all over the world
Reproductive isolation
prevents exchange of genes
allopatric theory of speciation from Mayr - geographic isolation caused by barriers that separate populations
Example - Isthmus of Panama separated closely related species of marine organisms, founder populations diverge and secondary contact does not result in breeding because genetic divergence during isolation prevents genetic compatibility
Fossil gaps and Macroevolution
Genealogical relationships are sometimes unclear until the discovery of missing links with intermediate characteristics of ancestors and descendants
Mosaic patterns of evolution - different morphological features of organisms evolve at different rates
Simpson - stressed the uneveness of the rates of evolution in different lineages (e.g., some faster versus slower), some lineages may experience a quantum leap in evolution versus others that are more gradual (beginnings of ideas of punctuated equilibrium)
Population size may play a role - smaller populations may evolve more quickly due to genetic drift
A modern theory of evolution
1930's - beginning of NeoDarwinism - new synthesis
1970's - Second period, new technologies in biochemical systematics, punctuated equilibrium versus gradualism
Natural selection at the species level?? - some species are selected for while others go instinct, confusions over the application of natural selection above the species level
Origin of higher taxa
descendant possesses a strikingly different feature from its ancestral population, need not be a major genetic re-organization
Evolutionary trends
increasing complexity from simple to advanced species, some may show no change or secondary simplification, some my show an increas in size (Cope's law), other lineages may show parallel evolution with distantly related groups resulting in evolutionary convergence
Concluding remarks
Evidence for evolution is irrefutable, going on around us all the time
Part of the problem with evolution is not separating humans from the process of nature
Interesting resources on Evolution versus Creationism debate
15 Answers to Creationist Nonsense
National Center for Science Education
Science and Creationism: A View from the National Academy of Sciences
Pope John Paul II's Message to Pontifical Academy of Sciences on October 22, 1996
Blackboard at Saint Anselm College
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Copyright © 2001 Jay Pitocchelli. All rights reserved. The contents of this page are the intellectual property of Dr. Jay Pitocchelli for distribution to students enrolled in Evolutionary Biology BI 25 at Saint Anselm College. These pages may not be copied, photocopied, reproduced, translated, or published in any electronic or machine-readable form in whole or in part without prior written approval of Jay Pitocchelli. Students enrolled in Evolutionary Biology BI 25 at Saint Anselm College have permission to print this material for their lecture notes.