EXAM 3 STUDY GUIDE
Skepticism & Intellectual openness
hallmarks of successful scientists - Skepticism: the need to see evidence (critical thinking) - Intellectual Openness: relative level of how you react to new information
Should evolution be taught in schools?
most people don't think that evolution should be taught in schools; or they think that it should be taught along with other "theories" of how things came about. - most people don't believe in evolution either.
According to the video, what was the "smoking gun" evidence that enabled the court to determine that the Intelligent Design textbook "Of Pandas and People" was a direct derivation of a rejected "Creation Science" textbook previously developed in the 1980's?
the author and editors botched the transformation of the text after the US Supreme court outlawed teaching "Creation Science" and mistakenly forgot to replace the words "creation scientists" with "design proponents" in their entirety
Evolution is...
the central organizing "scientific theory" of biology
What is evolution?
"to change" ("decent with modification") ("over time and across generations") - Populations change genetically across time and generations - change in allele (gene variants) frequency (proportions) from generation to generation ** Dominant/Recessive (every generation changes how often they occur and the proportions change)
"If man evolved from chimpanzees, why are there still chimpanzees?"
- A misconception of evolution (only say if you want to sound uneducated) - Scientific answer: evolution, common ancestors & primate "family tree" ** Primate karyotypes (chromosome analysis): fusion of chromosomes --- Human chromosomes (23 pairs; chromosome 2 produced by fusion) --- Chimp chromosomes (24 pairs; chromosomes "2a" & "2b") - they are our closest living relatives - where are the millions of between species? ** 7.7 billion people ** 170-300k chimps (down 90% in past 20 years) ** over 20 bipedal apes are known ** 7.0 mya
Evolution: views of the US public
- Basic trends: poll data indicates a low level of acceptance of evolution in US - Scientific acceptance: scientists overwhelmingly support validity of evolution (Miscommunication exists between scientists and the general public) - Effects of religious belief on the acceptance of evolution: varies greatly Support of Religions: **Buddhist: 81% ** Hindu: 80% ** Jewish: 77% ** Unaffiliated: 72% ** Catholic: 58% ** Orthodox: 54% ** Mainline Protestant: 51% ** Muslim: 45% ** Historically Black Protestant: 38% **Evangelical Christian: 24% ** Mormon: 22% ** Jehovan's Witnesses: 8% US is a pretty religious country - Effects of education and age on the acceptance of evolution: trends ** edu --- high school or less: 39% --- some college: 46% --- college graduate: 60% --- post graduate: 75% ** age --- 18-34: 50% --- 35-54: 40% --- 55 and older: 30% - Effects of sex and political affiliation on the acceptance of evolution: trends ** men: 65% ** women: 55% ** republicans: --- 2009: 54% --- 2013: 43% ** democrats: --- 2009: 64% --- 2013: 67% ** Independence: --- 2009: 67% --- 2013: 65: - Acceptance of evolution in US versus other developed nations: US ranking ** the US is below 50% compared to other developed nations in the acceptance of evolution (40%) - Acceptance of evolution in Iowa versus other states: IA ranking ** Iowa is below 50% in state rankings (40%)
Scientific evidence for evolution
- Genetic data (DNA sequences): confirms genetic relationships of tree of life ** compare base pairs between species (billions of them) - Shared ancestry: all organisms are related via common ancestry ** we share ~50% DNA with just about everything because the genes for basic things work so well - Pseudogenes: "silenced" genes that have been "turned off" and altered during the evolutionary history of specific lineages ** sense of smell (olfactory genes): because color vision was more important than smell, they became a pseudogene - Poor or bad design: examples of organismal design that is less than ideal; evidence that evolution "tinkers" with organisms; not created from scratch ** not trying to make perfect organisms (takes what is already there and adds to it for example testes or recurrent laryngeal nerve which is subject to damage) - Vestigial traits and atavisms: know specific examples and details of each ** Vestigial Traits: ancestral remnants or features co-opted for new purpose (old trait that still shows up) --- whale/dolphin: echolocation, complete loss of hind legs, blow hole --- tetrapods: nictitating membrane (3rd eye) "Plica Semilunaris" in human remanant --- Ostrich wings: threat displays and sheltering young (Exaptation: modified for a new purpose) --- modern python skeleton with vestigial leg bones with a different function ** Atavism: reawakening of gene (ancestral genes "re-activated" --- rare adult dolphins with atavistic hind limbs --- human atavistic tails or row of nipples --- lanugo: and embryonic fur coat (replaced by vellus hair then terminal hair) "Congenital Hypertrichosis Lanuginosa" - fetal lanugo is not replaced --- snakes with leg atavism (from lizard ancestor past) - Fossil record: evidence of evolutionary change in organisms across time ** more simple animals first ** horse fossils: started like bambi and ate like deer (forests); after warming period moved to prairies and got bigger because predators were big and ran faster - Transitional species: evidence of shared ancestry and macroevolution ** Archeopteryx: first transitional species discovered in 1860 (feathered dinosaurs) ** Homo neanderthalensis: extinct; shared genes with modern humans ** Tiktaalik: "fish with a neck, limbs, and a wrist" (transitional species between fish and amphibians—covered in Judgment Day: ID on Trial video) - Comparative anatomy: using anatomy to determine ancestry & relationships ** Homologous traits: similar features evolved from common ancestors (forelimbs of humans and monkeys) ** Analogous traits: similar features not evolved from common ancestors (bat wings and butterfly wings) - Developmental biology: evidence from comparing embryonic development (look a lot a like in early stages) - Speciation & hybrization: evidence from how species originate (species are "evolutionary accidents") ** some are split by geographic barriers and become enough genetically different that they can't breed anymore together ** Tigon, Liger, Jaglion, Zonkey, Geep, Mule, Savannah Cat **Most animals cannot hybridize because they have a certain number of chromosomes (Chimps and humans can't because chimps have 24 chromosomes and humans have 3) - Coevolution: species that develop close relationships track and respond to each other's evolutionary changes; know examples and details ** plant-pollinator (flower evolves and the fly responds) ** host parasite (lice and hosts) --- most mammals have lice that adopts to each species to grab onto different diameters of hair) --- humans have 2 and one is more related to the chimp lice and the other is more related to the gorilla lice ** predator/prey - Antibiotic resistance: bacteria can quickly evolve genetic changes in response to their chemical environment (if you don't take all your medication you are only causing the strong ones to survive ** Harvard Petri Block (shows that antibiotics kill bacteria and good bacteria to make conditions ideal for the string bacteria to take over and evolve) - Artificial selection: human driven selective breeding creates evolutionary changes in plants and animals ** dog breeds in the last 100-200 years: shapes, sizes, hairless ** plant breeds: wild mustard --- cabbage, brussel sprouts etc. ** corn: Teosinte to intermediates to modern corn which is huge ** watermelon, peaches, grapes
Intelligent Design (ID)
- Intelligent Design (ID): pseudoscience; a collection of beliefs or practices mistakenly regarded as being based on scientific method. - Irreducible complexity: some biological structures are "too complex" to have been produced via biological evolution; functional parts are designed by a designer and cannot be removed or altered (i.e., "exaptation" does not occur) ** Examples: bacterial flagellum, blood clotting systems, mousetraps
How does Evolution work?
- Mutations (a random process that creates genetic diversity & change via mutations: deletions = when a part of a chromosome is left out duplication = part of chromosome is replicated insertions = when part of the chromatid breaks off and attaches to its sister chromatid (duplication of genes on same chromosome) inversions = part of chromosome breaks off and reattaches backwards translocations = part of one chromosome breaks off and is added to a different chromosome ** sex promotes genetic diversity due to "crossing over" during gamete formation ** provides the "raw material" for evolution ** genetic change and genetic variation - Natural selection ( --- stabilizing selection = for modern traits against both extremes (robins usually lay 4 eggs; more is malnourished and less is no livable off spring) --- directional selection = one extreme trait against the other (light colored pepper moths are more camouflaged than dark colored in prestige environment, but dark is more in sooty environment so shift to dark; another example is size of horses) --- disruptive selection = for both extremes against moderate traits (squirrels short tails help keep predators from catching you, and long tails are good for balance in trees, medium tails do nothing; gray and white rabbits better blend in than black so both reproduce) --- balancing selection = involves a number of selective processes that maintains the presence of multiple alleles at a particular gene locus in the population's gene pool, so functions to conserve genetic polymorphism (the rich diversity of shell patterns observed in grove snails) --- sexual selection = members of one biological sex choose mates of the other sex to mate with, and compete with members of the same sex for access to members of the opposite sex (colorful feathers of peacocks or big antlers of deer) influences which individuals leave their genes in relative proportions from one generation to the next in each population; NOT a random process; ** the nonrandom survival of random variants - Gene flow: nonrandom gene dispersal due to immigration and emigration ** the exchange of genes between two populations (birds with shorter beaks or brown beetles) - Genetic drift: a random process that influences allele frequencies via the "founder effect" and/or "population bottlenecks") -- alternating gene frequencies ** founder effect: random change in allele frequency; In small populations, individuals that carry a particular allele may have more descendants than other individuals do. over time this causes the allele to become more common in that population (small number of organisms move to a new area ** population bottlenecks: drastic reduction in population; reduces size and genetic diversity (due to catastrophic event)
Evolution: US court cases
- Zorach v. Clauson, 1952 (religious studies) - Engel v. Vitale, 1962 (no mandatory prayer or Bible reading in schools - Epperson v. Arkansas, 1968(state laws banning teaching of human evolution ruled unconstitutional) - Mississippi last state to nullify ban on teaching human evolution 1970 - Edwards v. Augillard, 1987 (evolution and creationism) - court ruled 7 to 2 Louisiana's law of requiring balanced treatment for creationism was unconstitutional - Westside community schools v. mergens 1990 (student religious groups) - John E. Peloza v. Capistrano Unified School District, 1994 (Evolution is not a religion; a school can require that a teacher teach evolution) - not a religion - Freiler v. Tangipahoa Parish Board of Education, 1999 (teachers cannot be required by school administrators to read aloud anti-evolution disclaimers) - ID was same as teaching creationism - Association of Christian Schools et al. v. Stearns et al., 2010 (Admissions policy of U of Cal regarding rejection of certain high school biology classes from Christian schools ruled constitutional and properly applied) - declined review of freedom of speech ect.
According to the video, what is a "transitional fossil"?
- a fossil of an extinct species that "bridges the gap" between 2 major groups - a fossil with traits of 2 major groups, linked through common ancestry
What is a "tetrapod"?
- a group of vertebrate land animals that evolved from a common ancestral group of fish, and generally have 4 limbs - any amphibian, reptile, bird, or mammal, even those without limbs
The Meaning of Life (Sean Carroll, astrophysicist):
- naturalism: one material existence (we are part of the universe) - we have to go out and look at the world to learn - we have debate because religion provides people with purpose and meaning in life - we create our own meaning (you need to find your own meaning)
According to the video, evolution by "natural selection" involves which of the following?
- organisms complete for limited resources (food, territories, mates, etc) - nature "selects" individuals that are best suited to a particular environment - changes in the proportional numbers of genes and traits occur across generations - species are nor fixed and may change genetically over time - ALL OF THE ABOVE
Which of the following describe the views of "Creationists":
- rejection of modern science and the conclusions generated by it - favor a literal interpretation of ancient religious texts - believe earth is less than 10,000 years old - reject evolution as a biological explanation of life's diversity and relatedness - ALL THE ABOVE
Human Values (Sam Harris, cognitive neurobiologist
- relationship between science and values - science cannot tell us what to value - the split is an illusion (there is a connect) ** values reduce to facts - scientific truth is not predicated on convincing everyone ** value of respect for evidence; logical argument, intellectual honesty; people fail to collaborate - some people believe in the wrong things
Scientific theories, scientific laws, & "incontrovertible theories"
- scientific theories: strongest level of support in science ** a well supported explanation for a series of tested observations and facts ** not just a guess or a law in the making - scientific law: the description of an observed phenomenon - "incontrovertible theories: theories that cannot be denied or disputed.
Which of the following are examples of well-supported and well-documented "scientific theories": (a few among many, many others)
-the germ theory - the theory of gravitational force - the theory of friction - atomic theory (theory of atoms and their existence - the theory of evolution - the spherical earth theory **ALL OF THE ABOVE scientific theories are highly supported by evidence and provide accurate explanations for observed facts of nature
According to the video, what % of the US population does NOT currently accept the science of evolution?
33-50%
True/False: "Irreducible complexity" as defined by Michael Behe and ID proponents, has never been adequately addressed or refuted by evolutionary biologists.
False
True/False: According to the video, a "scientific theory" is mostly a guess or idea that is generally NOT associated with a large body of evidence
False
True/False: According to the video, the 20th and 21st century fields of modern genetics and molecular biology REFUTE the observations that were made in the 1800's (by Charles Darwin and others) as evolutionary theory was first being conceived and developed
False
Antievolution wave
First Wave: 1920's - 1968 (Banning Evolution) - Scopes v. Tennessee (1925-1927) "Scopes Monkey Trial" - bans were ruled unconstitutional in Epperson v. Arkansas (1968) Second Wave: 1969 - 2005 (Balancing Evolution with Biblical creation - 1970s) - Daniel v Waters (1975) (Creation Science - 1970-1987) - McLean v. Arkansas (1982) - Edwards v. Aguillard (1987) (Intelligent Design - 1987-2005) - Kitzmiller v. Dover (2005) Third Wave: 2004-present (Stealth creationism: requiring or encouraging "critical analysis" of evolution and other topics, usually by teaching long debunked creationist arguments, but without using the terms "creationism" or "intelligent design") - None yet. Policies passed in Mississippi, Louisiana, and Tennessee
NOMA
Non-Overlapping Magisteria - science and religion occupy different realms and can "accommodate" each other by addressing different questions ** Science: determines the how, why, and when by using repeatable, testable methods to measure the material world ** Religion: addresses questions of values, provides alternative answers to origins, may offer a sense of purpose or meaning that is not self-derived
According to the video, what textbook was being considered in the Doer, PA school district as an "alternative" to established, peer-reviewed, science-based Biology textbooks?
Of Pandas and People
Arguments against evolution (& some responses)
Platitudes, misconceptions, & direct lies - Why aren't there any crocoducks? (mutations are random and sometimes that right mutations don't happen; you can't just pick them) - Where are all the missing links? (transitional fossils) - There are no transitional fossils - I've never seen a dog turn into a cat. - Accepting evolution robs you of life's meaning - If man is just an animal then we will act like beasts - If man evolved from chips then why are there still chimps? - microevolution is true but not macroevolution - evolution is not observable. - carbon dating doesn't work (not accurate for animals who don't get carbon from the atmosphere) ** Carbon dating: using the relative levels of the radioactive isotope of Carbon (C-14) to determine the age of organic material less than 60,000 - 80,000 years old; most accurate when used to date material that originally obtained carbon directly from atmosphere
Which of the following is an important transitional fossil species that "bridges the gap" between fish and amphibians?
Tiktaalik roseae, a fish with a neck, flat head, wrist, and arm bones similar to that found in most most amphibians, reptile, birds, and mammals
True/False, According to most (established and respected) scientists, "intelligent design" is NOT a scientific concept.
True
True/False: According to the video, ALL scientific theories are tentative and are subject to future revision, no matter how much evidence currently supports them
True
True/False: According to the video, NO scientific theory should be regarded as "absolute truth"
True
True/False: The US Federal Judge assigned to the ID trial (Judge John E. Jones III) was a Christian republican who was appointed by republican President George Bush.
True
True/False: The US Supreme Court ruled in 1987 that the teaching of creationism in public school science classes violated student's constitutional rights/
True
True/False: the central tenet of Intellectual Design (ID) is that, due to the complexity of life, "some aspects of life must be the result of design from a designer that represents an intellectual cause or intelligent agent"
True
Examples of other scientific dating methods
ages confirmed by analyzing objects of known age, being tested by multiple techniques, & multiple groups of scientists from multiple research labs - Radiometric dating: radioactive isotopes of elements with different 1/2-lives ** Carbon-14 = 5,730 ** Potassium-40 = 1.3 bil ** Uranium-238 = 4.5 bil ** Thorium = 14 bil ** Rubidium-87 = 49 bil - Dendrochronology: analyzing tree ring data, including deriving ages from single trees and overlapping ages of multiple trees from specific regions across time - Thermoluminescence: deriving ages from measuring trapped electrons (how long ago something was last exposed to sun light - Dating rocks: using the position of layers and analyzing radioactive isotopes ** Earth rocks: existing rocks are slightly younger than the actual age of the earth & solar system; older rocks destroyed or not at Earth's surface ** Space rocks: meteorites, rocks from Mars, and rocks from the moon (Dating of material from space yields similar dates (~4.5 x 10-9 years) - writing - paleomagnetic: (polar wandering) - amino acid racemization - electron spin resonance - fission track - potassium-argon - paleomagnetic (polar reversal)
Tree of Life
depicts relationships & common ancestry of all life forms
Cognitive dissonance & confirmation bias
human psychological reactions - Cognitive dissonance: the mental discomfort (psychological stress) experienced by a person who simultaneously holds two or more contradictory beliefs. **triggered by a situation in which a belief of a person clashes with new evidence perceived by that person. ** When confronted with facts that contradict personal beliefs, ideals, and values, people will find a way to resolve the contradiction in order to reduce their discomfort, often reaffirming their previous beliefs with confirmation bias. - Confirmation Bias: the tendency to interpret new evidence as confirmation of one's existing beliefs or theories.
Which of the following represents a recently discovered example SUPPORTING the evolution of humans from nonhuman primates?
humans have 23 chromosomes even though other living primates have 24, and the difference resulted from a fusion of 2 chromosomes into a single chromosome during the evolution of modern humans
Creation-Evolution (CE) Continuum
mostly applies to the 3 "Abrahamic Faiths:" Judiasm, Christianity, Islam; does not directly apply to Buddhism or Hinduism - Young earth (Flat earthism, Geocentrism, YEC): the earth is flat, the center of the solar system & universe, and less than 10,000 years old; species are created independently and are not related, species can only breed within their kind, humans were created via supernatural processes separately from animals - Old earth (accepts geological & chemical sciences determining age of earth) ** Gap creationism: a long time "gap" between the 1st and 2nd chapters of genesis explains Earth's age; "days of creation" are 24 hour days (but the Sun wasn't created until the 3rd day) ** Day-Age creationism: each of the 6 days of creation represent "long geologic ages" (not 24 hours) to explain Earth's age of 4.5 billion years ** Progressive creationism: accepts the physics of the Big Bang, the 13.8 billion year old age of the universe and Earth's age, and the nature of fossils, but does not accept much of biological science (e.g., species do not evolve from each other) ** Evolutionary creationism: Monotheistic God actively & closely directs evolution ** Deistic evolutionism: Monotheistic God loosely directs evolution or only "got the ball rolling" then let natural processes occur (this is the stance of most Mainline protestant Christian religions, Catholicism, and many scientists) ** Methodological materialist (Agnostic): only the material world ("reality") exists, science is the best (or only) method to determine and measure the natural world; "no comment" on the existence of supernatural beings or causes ** Philosophical materialist (Athesist): only the material world ("reality") exists, science is the best (or only) method to determine and measure the natural world; no supernatural beings or causes exist
Creationist & Scientific perspectives
provide contrasting explanations for the origins of the universe, stars, planets, life on Earth, origins of humanity, etc - about 75 colleges teach creationism (1.6%) - 7 of those teach young earth creationism (0.15%) - there are over 4600 colleges