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WORKSHOP on the ORIGIN OF LIFE by Dana Krempels I. Conditions of the Early Earth 1. Consider the Stanley Miller apparatus. What was it meant to simulate? All the answers to questions #1 - 5 can be found at: http://www.bio.miami.edu/dana/160/160S16_2.html and/or our old pal: https://en.wikipedia.org/wiki/Miller-Urey_experiment BE SURE YOU KNOW THESE ANSWERS BEFORE THE WORKSHOP. 2. What elements and compounds were present in the apparatus in a. gaseous form methane, ammonia, hydrogen b. liquid form water 3. What energy source(s) were provided, and what was each meant to simulate? electrodes - lightning, heat source - volcanic heat 4. What products were found in the apparatus after it was allowed to operate for various amounts of time, and under various conditions? See: https://en.wikipedia.org/wiki/Miller-Urey_experiment#Chemistry_of_experiment And: https://en.wikipedia.org/wiki/Miller-Urey_experiment#Other_experiments 5. What element was notably absent from the earth's primordial atmosphere, and why was this absence essential to the formation of life? OXYGEN. Because organic molecules decay rapidly in an oxidizing atmosphere, their stability might have been insufficient for life to form if oxygen had been present on primordial earth. In the absence of oxygen, many organic molecules are relatively stable. II Components of Life 1. What is the definition of a biological macromolecule? a polymer of repeating subunits of either amino acids (protein), nucleotides (nucleic acid), sugars (carbohydrate) or fatty acids (lipid) 2. Name two common examples of each of the following types of macromolecule: a. nucleic acid DNA, RNA b. protein silk, hair, toenails, muscle proteins, etc. etc. etc. c. carbohydrate glycogen, cellulose, starch, sucrose, glucose, etc. d. lipid waxes, oils, fats III. Science vs. Religion: Where did Life on earth come from? Humans have probably been debating the question of the origin of life since they huddled around campfires at night with nothing to do but chew bones and attempt to make more humans. Many cultures have creation stories very different from the ones most commonly taught in the U.S., which are based on biblical stories. Stephen Jay Gould said that “Science and Religion are two means by which humans seek Truth.” In Science, observable phenomena are required for verification. In Religion, the only verification required is faith. Today you will discuss and decide which of several fairly well-known ideas about the origin of life are within the realm of natural science, and which are best considered part of other disciplines. First, it is important to distinguish between 1. The origin of life on earth 2. The evolution of life The origin of life is not yet completely understood, although scientific experiments since Miller-Urey are yielding new data about life’s origins. For example: http://www.pbs.org/video/1790640610/ But there are other ideas about where life came from. A. Cosmic Ancestry: Panspermia 1. Cosmic Ancestry? A hypothesis popular in some circles suggests that Life originated as a result of the "seeds of life" (e.g., primitive cells, macromolecules, etc.) having been carried here on meteorites. This idea is sometimes known as "panspermia". Use your Dictionary of Word Roots and Combining Forms (Borror) to determine the meaning of "panspermia." Write it here: pan = "everywhere" sperm = "seed" 2. What do you suppose the literal translation of this word refers to? That the "seeds of life" exist everywhere in the universe. 3. Pose some testable research ideas that might help determine whether this idea has any truth. 1. Examine known meteoric debris on earth for signs of organic substances. 2. Sample potential meteoric material still in outer space (Note that many of the experiments/field collections that could be used to test this idea are not within our technological capabilities at this time. Does this mean they are not scientifically testable?) 4. Is the notion of "panspermia" within the realm of science? DISCUSS. It has the earmarks of a scientifically testable hypothesis, though many of the methods needed to test it are beyond our technological capability at this time. It does not rely on faith as an explanation for observable phenomena. B. Creation Science In many religious traditions, including those of the three Abrahamic faiths (Judaism, Christianity and Islam), life is said to have originated at the hand of divine creator. A group of people who believe in the literal translation of Biblical creation founded the Institute of Creation Research (ICR), which purports to demonstrate that the idea of divine creation is scientifically testable. They have dubbed this field "Creation Science." The "creation scientists" stated that their version of the origin of life is scientific, not religious, in nature, and hence should be taught in public school science classes alongside scientific ideas about life’s origins and evolution. The nine main tenets of "Creation Science," as stated by the ICR are listed below. For each one, you’ll be asked to decide whether it is (1) an observable fact or (2) a falsifiable hypothesis If you feel it is a falsifiable hypothesis, you will- be asked to design an experiment to test it. Based on this, you will decide whether the tenet is scientific or not. Tenet 1. "The physical universe of space, time, matter and energy has not always existed, but was supernaturally created by a transcendent personal Creator who alone has existed from eternity." 1. Does this tenet describe a physically observable, verifiable fact? Although we know that the universe came into being nearly 14 billion years ago, there is no verifiable evidence that this was at the hand of a supernatural creator. 2. If so, what physical evidence exists to support this idea? ICR would claim that the mere existence of the universe supports this idea. Is this scientifically valid? 3. What evidence exists to refute it? The existence/activity of a supernatural creator cannot be subjected to scientific refutation. 4. Can you design a testable hypothesis regarding this tenet? You can try. 5. Is this tenet scientific? No. Tenet 2. "The phenomenon of biological life did not develop by natural processes from inanimate systems but was specially and supernaturally created by the Creator." 1. Does this tenet describe a physically observable, verifiable fact? No. 2. If so, what physical evidence exists to support this idea? ICR would claim that the existence of life is proof of its creation. A circular argument. 3. What evidence exists to refute it? Natural processes have been demonstrated to be capable of forming the building blocks of life on their own, without the intervention of a supernatural power. This does not exactly refute the tenet, which is untestable. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: Again, this is going to be a bit of a challenge. 5. Is this tenet scientific? No. Tenet 3. "Each of the major kinds of plants and animals was created functionally complete from the beginning and did not evolve from some other kind of organism. Changes in basic kinds since their first creation are limited to 'horizontal' changes (variations) within the kinds, or 'downward" changes (e.g., harmful mutations, extinctions)." NOTE: Here, ICR moves from Origin of Life to Evolution of Life. 1. Does this tenet describe a physically observable, verifiable fact? ICR would claim that fossils are evidence of a “downward” change and that variations among similar species are evidence of “horizontal”: changes. 2. If so, what physical evidence exists to support this idea? Fossils? The existence of harmful muations? 3. What evidence exists to refute it? Fossil record: Progression of complexity over time in known lineages. Homologies in living species: ontogeny, morphology, molecular Biogeography: Related species distribution reflected in geographic changes Observed speciation events: http://www.talkorigins.org/faqs/faq-speciation.html 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: The contention that the complexity of organisms was the work of a divine creator cannot be tested. Predictions about homology at various levels can be formulated and put to the scientific test, but they do not involve refutation of divine creation. 5. Is this tenet scientific? No. Tenet 4. "The first human beings did not evolve from an animal ancestry, but were specially created in fully human form from the start. Furthermore, the 'spiritual' nature of man (selfimage, moral consciousness, abstract reasoning, language, will, religious nature, etc., is itself a supernaturally created entity distinct from mere biological life." 1. Does this tenet describe a physically observable, verifiable fact? The qualities of humans listed are observable fact, and some of them appear to be unique to humans, or at least present in only a few other species. But the idea that these were divinely created cannot be observed, as it supposedly happened in the distant past. There is no physical record of humans being divinely created. 2. If so, what physical evidence exists to support this idea? The described characteristics of humans are the only evidence. There is no physical, observable evidence to indicate divine creation of those characteristics. 3. What evidence exists to refute it? Presence of “spiritual” characteristics “unique to humans” could be considered evidence to the contrary. If humans’ spiritual nature was divinely created and unique to humans, then one should predict that no primordial of these traits exists in other species. However, chimpanzees, elephants, and dolphins have been demonstrated to be able to recognize themselves in a mirror (a classic test of self-awareness). Chimpanzees have been taught American Sign Language, and can devise their own sentences and communication from those tools. Elephants appear to understand the concept of death, and may return to the site of a herdmate’s death and leave tokens at the spot of death. Great apes (e.g., Koko) also appear to wonder about a concept of death. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: One could make a prediction that if these things existed in their current form from their inception, there should be no evidence of more primitive forms in other species or in the fossil record. This could be tested. 5. Is this tenet scientific? Partially testable, but the contention that the human characteristics were divinely created is not testable. Tenet 5. "The record of earth history, as preserved in the earth's crust, especially in the rocks and fossil deposits, is primarily a record of catastrophic intensities of natural processes, operating largely within uniform laws, rather than one of gradualism and relatively uniform process rates. There are many scientific evidences for a relatively recent creation of the earth and universe, in addition to strong scientific evidence that most of the earth's fossiliferous sedimentary rocks were formed in an even more recent global hydraulic cataclysm." 1. Does this tenet describe a physically observable, verifiable fact? The above is stated as a hypothesis, which should be subject to verification. 2. If so, what physical evidence exists to support this idea? The ICR puts forth evidence “for” creation, but does not state testable hypotheses. In science, hypotheses must be refutable, or they are not scientific. ICR would claim that the mere existence of the fossil record in its state could be described by the cataclysm. Prediction: If the fossil record was created by a flood, then there should be geological evidence of a massive, global flood that happened less than 6000 years ago. This could be testable. 3. What evidence exists to refute it? Copious geological evidence, including radiometric dating, tells us that the earth is millions of years old, and that the rocks and fossils in it have been produced by natural events that can be seen to be occurring now, as well. This does not directly refute the ICR tenet, as it is not stated as a refutable hypothesis. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: Again, one could make predictions regarding what to expect from the fossil record if natural, observable geological process are responsible for them. 5. Is this tenet scientific? It is potentially testable. Tenet 6. "Processes today operate within fixed natural laws and relatively uniform process rates (this part is observable) but, since these were themselves originally created and are daily maintained by the Creator (this part is not observable nor testable), there is always the possibility of miraculous intervention in these laws or processes by their Creator. Evidences for such intervention should be scrutinized critically, however, because there must be clear and adequate reason for any such action on the part of the Creator." (this part is not observable nor testable) 1. Does this tenet describe a physically observable, verifiable fact? This tenet basically says that the earth follows natural laws created by a supreme being, but that the same supreme being can break those laws, should she/he/it wish to do so. But that she/he/it has to have a “good reason” for doing so. It is not possible to test whether a supreme being has broken the laws of nature for a “good reason”. 2. If so, what physical evidence exists to support this idea? No evidence of laws of nature being broken by a supreme being so far. 3. What evidence exists to refute it? The laws of physics have so far been stable on earth. But this is support of the hypothesis, not refutation. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: Try your best. 5. Is this tenet scientific? No. Tenet 7. The universe and life have somehow been impaired since the completion of creation, so that imperfections in structure, disease, aging, extinctions and other such phenomena are the result of 'negative' changes in properties and processes occurring in an originally-perfect created order." 1. Does this tenet describe a physically observable, verifiable fact? The presence of “imperfections” in living things is evident. But the imprecise “somehow” of their origin is not observable, nor suggested by the tenet. 2. If so, what physical evidence exists to support this idea? The ICR considers existence of imperfection to be evidence. 3. What evidence exists to refute it? There is no evidence to show that a divine creation was somehow impaired. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: No. 5. Is this tenet scientific? No. Tenet 8. Since the Universe and its primary components were created perfect for their purposes in the beginning by a competent and volitional Creator, and since the Creator does now remain active in this now decaying creation, there do exist ultimate purposes and meanings in the universe. Teleological considerations, therefore, are appropriate in scientific studies whenever they are consistent with the actual data of observation, and it is to assume that the creation presently awaits the consummation of the Creator's purpose." 1. Does this tenet describe a physically observable, verifiable fact? We have left the realm of pretend science and entered the real of pure faith. 2. If so, what physical evidence exists to support this idea? None. 3. What evidence exists to refute it? None. 4. Can you design a testable hypothesis regarding this tenet? If so, write it here: Since the tenet regards the purpose of a Creator whose existence cannot be verified, no. 5. Is this tenet scientific? No. This is a matter of faith, not science. Tenet 9. "Although people are finite and scientific data concerning origins are always circumstantial and incomplete, the human mind (if open to the possibility of creation) is able to explore the manifestations of that Creator rationally and scientifically and to reach an intelligent decision regarding one's place in the Creator's plan." 1. Does this tenet describe a physically observable, verifiable fact? It is observable and verifiable that humans can explore the possibility of the existence of a divine creator. However, the statement that one can “reach an intelligent decision regarding one’s place in the Creator’s plan” pre-supposes the existence of said creator, which cannot be verified with observation. 2. If so, what physical evidence exists to support this idea? It is true that humans think about the existence of a divine creator. It is not necessarily true that one can reach an intelligent, rational decision about one’s place in the plan of an entity that cannot be demonstrated to exist. 3. What evidence exists to refute it? None. It cannot be refuted, as it invokes the unobservable and untestable. 4. Can you design a testable hypothesis regarding this tenet? No. 5. Is this tenet scientific? No. 6. Is "Creation Science" within the realm of science? Discuss. While ICR tenets try to frame their belief in the context of observable phenomena, their insistence that these phenomena are the result of a divine creator’s “hand” cannot be verified nor tested. Hence, it is not scientific. It is based on faith in the unobservable/unknowable. 7. What are the differences between a hypothesis that is scientifically testable and one that is not? Which of the three ideas about the origin of life described here can be scientifically tested? A scientific hypothesis is devised based upon a prediction of what one should observe if an over-arching theme/idea (theory) is true. For example: Theory: Evolution proceeds by means of natural selection. Prediction: If natural selection causes populations to evolve, then there should be differential reproduction between individuals in a population subjected to a selective factor. Hypothesis: Choose your population and devise the hypothesis. This has been done thousands of times, and natural selection has been observed (not refuted) thousands of times. The untestable tenets put forth by the ICR cannot be phrased as testable hypotheses. They are not scientific. The ideas of panspermia are within the realm of (potentially) scientific testability. Creation science tenets are not. C. Scientific Creationism vs. Darwin in the Courtroom Several times in the recent past, Creation Scientists have gone to court in an attempt to have creation science replace evolutionary theory in public school science classes. Rather than champion any scientific strengths of the tenets of creation science, those arguing for creation science in the classroom point out "weaknesses" in evolutionary theory. One Creation Scientist has claimed, "A major goal of creation science is to point out the weakness of evolutionary theory, because basically there are only two alternatives for how we got here, and if naturalistic processes are incapable of the task, then special creation must be the correct answer." 1. Do you agree with the statement above? Discuss it objectively and dispassionately. It's true that creation scientists spend far more time trying to "poke holes" in evolutionary theory than in demonstrating the testability of their own ideas, which are not scientifically testable. Recall the difference between the evolution of life and the origin of life. One of the major weaknesses of the creation science movement is its inability to understand that a scientific hypothesis is a tentative explanation for a phenomenon, and that a theory is a well-supported explanation for how some aspect of the natural world works. (Even theories are subject to revision.) One cannot truly say that "naturalistic processes are incapable of the task" of driving evolution. One can say only that some processes are not currently/readily testable--usually for lack of sufficient time or technological capability. This does not mean that ideas about such processes are not scientific in nature 2. In their efforts to gain credibility for creation science, its proponents often claim that "evolution is only a theory and hasn't been proven." Discuss this assertion. Is it correct? First, the people who say that evolution is "only a theory are failing to separate two notions: 1. Evolution is an observable phenomenon. We can see microevolution happening as bacteria become resistant to antibiotics, weeds become resistant to pesticides, etc. We can see extremely strong evidence for evolution as a past phenomenon in the homologies of organisms' morphology, embryo development, and DNA/RNA sequences. The fossil record provides further, if incomplete, evidence that there has been descent with modification through time. 2. Natural selection is one means by which evolution occurs. THIS was Darwin's idea. He was not the first to propose that evolution happens. But he was the first to propose a mechanism for which there was copious evidence that could be subjected to scientific verification (but not refuted, unlike Lamarck's earlier idea that acquired characters could be passed on to offspring). Furthermore, one cannot PROVE a scientific hypothesis or theory. One can only subject it to potential falsification. Darwin’s theory of natural selection not only explained things that Darwin himself could observe (differential reproduction), but also had room to accommodate new discoveries about how traits are passed on (discovery of DNA and greater understanding of the molecular basis of inheritance). 2a. In science, what are the precise definitions of hypothesis – A supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation. It is a rational explanation of a single event or phenomenon based upon what is observed, but which has not been tested or proven. Recall that a hypothesis is never subjected to experimental examination to prove that it’s true. The results of a properly designed experiment allow the investigator to either reject or fail to reject a given experimental hypothesis, not prove that it is true. “Acceptance” of a hypothesis is provisional. theory In science, the term theory has a very precise meaning that is quite different from the colloquial use of the term. A theory is intended to be an accurate, predictive description of the reason for an observed phenomenon in the natural world. A theory can be used to make predictions about the phenomenon in question. law A scientific law is a statement based on repeated experimental observations that describes some aspects of the universe. A scientific law always applies under the same conditions, and implies that there is a causal relationship involving its elements. A scientific law does not provide an explanation for a phenomenon. It is accepted at face value because it has always been observed to hold true. Thus, a scientific law is simple, true, universal, and absolute. As such, it forms a cornerstone of investigation and discovery in its area, and is the basis of hypothesis formulation. Examples: • The Law of Gravity • Newtonian Laws of Motion • Laws of Thermodynamics • Boyle's Law of Gases IV. Science vs. Religion: How did life change once it arrived on earth? The evolution of life, unlike the origin of life, proceeds via mechanisms that we can observe and test with scientific methods. A. Evolution by Means of Natural Selection 1. By now, you are familiar with Charles Darwin's observations and inferences regarding organic evolution by means of natural selection. His work is sometimes distilled down into four basic tenets of evolution by means of natural selection. What are the four tenets? Tenet 1. All organisms can produce large numbers of offspring (OVERPRDUCTION) Tenet 2. These offspring have variable, heritable characteristics (HERITABILITY) Tenet 3. Organisms must compete for limited resources. (COMPETITION) Tenet 4. Those individuals whose (heritable) physical characteristics make them best suited to exploit resources will leave the most offspring to future generations. (DIFFERENTIAL REPRODUCTION) 2. Consider each of the above tenets. Which are observable/verifiable facts? If a tenet does not describe an observable fact, then can it be tested scientifically? If so, suggest a research question and experiment that addresses this tenet. Tenet 1. OBSERVABLE FACT (have them give examples) Tenet 2. OBSERVABLE FACT (have them give examples, understand WHY) Tenet 3. TESTABLE (give example of a simple test) Tenet 4. TESTABLE 3. Which of the above tenets are now known to be indisputable fact? Tenets 1, 2, and 3 are fairly indisputable. 4. Which are not yet known to be true? Tenet 4, despite repeated experiments designed to test it, has not been refuted. A THEORY is an explanation for an observable fact. Natural selection is a very well supported theory. 5. Of the latter, what evidence exists to support it/them? Find an example with the Mycobacterium in AIDS patients here: http://www.bio.miami.edu/dana/160/160S16_5.html 6. What evidence exists to refute them? None so far. (Don't confuse kin selection with altrusim/lack of competition; see this lecture: http://www.bio.miami.edu/dana/160/160S09_6.html and read the parts under Sociobiology. 7. Are Darwin's tenets scientific? DISCUSS. Yes. All four tenets are either observable fact or testable via the scientific method E. Intelligent Design " A more recent proposal replacing naturalistic mechanisms to explain evolution is known as Intelligent Design (ID). Questions #1-3 are preceded by excerpts from www.intelligentdesign.org shown below in green. Certain phrases have been italicized. Pay special attention to those for discussion. The theory of Intelligent Design (ID) holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection. 1. Is natural selection an undirected, random process? Discuss. Through the study and analysis of a system's components, a design theorist is able to determine whether various natural structures are the product of chance, natural law, intelligent design, or some combination thereof. Such research is conducted by observing the types of information produced when intelligent agents act. 2. Is the above a description of the modern scientific method using falsifiable hypotheses? Discuss. Scientists then seek to find objects which have those same types of informational properties which we commonly know come from intelligence. Intelligent design has applied these scientific methods to detect design in irreducibly complex biological structures, the complex and specified information content in DNA, the life-sustaining physical architecture of the universe, and the geologically rapid origin of biological diversity in the fossil record during the Cambrian explosion approximately 530 million years ago. 3. Are any of the ID ideas supported by observable evidence or processes? Discuss. 4. Are any of these ideas falsifiable? If so, design an experiment that would put the idea to the test. Is Intelligent Design a scientific theory? Yes. The scientific method is commonly described as a four-step process involving observations, hypothesis, experiments, and conclusion. Intelligent design begins with the observation that intelligent agents produce complex and specified information (CSI). Design theorists hypothesize that if a natural object was designed, it will contain high levels of CSI. Scientists then perform experimental tests upon natural objects to determine if they contain complex and specified information. One easily testable form of CSI is irreducible complexity, which can be discovered by experimentally reverse-engineering biological structures to see if they require all of their parts to function. When ID researchers find irreducible complexity in biology, they conclude that such structures were designed. 5. Is the assumption that something with a high level of "CSI" scientifically testable? Discuss the above passage and decide whether it is consistent with the scientific method. CSI is present in all living things. However, it not necessarily true that everything exhibiting CSI must be the product of an intelligent designer. This is a leap of faith. Natural processes have been demonstrated to be fully capable of producing CSI. Life on earth has been evolving for 4.5 billion years. We have been studying this process for just over 200 years. For us to duplicate this process in such a short time, even if we understand the mechanisms, would be unlikely. Vast amounts of physical evidence point clearly to natural and other processes (mutation, genetic drift, assortative mating, etc.) being sufficient to explain the complexity and diversity of life. A supernatural explanation is superfluous and not scientifically testable. Stephen Jay Gould said that “Science and Religion are two means by which humans seek Truth.” In Science, observable phenomena are required for verification. In Religion, the only verification required is faith. The two means of seeking truth are not comparable. Natural History magazine published a series of “point/counterpoint” essays written by ID proponents and evolutionary biologists. Read them here: http://www.actionbioscience.org/evolution/nhmag.html 6. Are the ID proposals and counter-arguments testable, or supported by observable evidence? 7. The United States Constitution disallows the establishment of a state religion. Hence, it is illegal to teach religious doctrine--of any faith--in public schools. Given what you have discussed today, do you believe that creation science should be taught in public schools? DISCUSS. The tenets of scientific creationism are not scientifically verifiable or testable. Hence, they do not fall within the realm of science. The assumptions of Intelligent Design are flawed. Hence, the "hypotheses" they purport to test based on these assumptions are invalid. Both scientific creationism and Intelligent Design are thinly disguised transcriptions of Biblical myth written as pseudoscience designed to be attractive to people with little or no background/understanding of natural science or the scientific method. Hence, it would be unconstitutional to allow either creationism, creation “science” or ID to be taught in public school classrooms, which are government funded, as this would breach the constitutional barrier between establishing a state religion. Because scientific creationism and ID are both based on Abrahamic (primarily fundamentalist Christian) beliefs, they should not even be taught as fact in any context in public schools. There are many different creation stories across cultures, and teaching only one as fact would create an unfair bias against faiths with different creation mythologies. Teaching something as fact should be distinguished from teaching about a certain school of thought. For example, it is completely acceptable in the College of Arts and Sciences to have courses in Religion, as long as the courses focus on the structure and history of that religion. It is NOT acceptable practice in academic institutions to offer a course that 's about converting students to a particular faith or spiritual practice. The same is true in public schools. "When evolution is outlawed, only outlaws will evolve." --Jello Biafra