Physical Anthropology K. Markley First Day General Survey Are the following statements true or false? Write an F or T next to each question (you will NOT be graded on this survey, this is an introduction to the class). 1. The key methodology in science is whether or not hypotheses can be tested. Science can be used to answer all of the questions that humans have about the world. 2. Science can prove facts but theories are always a matter of opinion and debate. All opinions and theories are given equal voice in the scientific community. 3. Survival of the fittest (in Darwinian natural selection) is all about being the biggest, the strongest, and the smartest. 4. Charles Darwin’s stated that humans evolved from apes. His theory of natural selection has been dramatically revised since it was first formulated and is hotly debated in biology today. 5. Four DNA bases, adenine, guanine, thymine and cytosine are the basis for all life on earth. All life on earth; bacteria, flowers, dogs, and humans is coded for by these four DNA bases. 6. All typical humans have 23 pairs of chromosomes. However males are more likely to get a variety of genetic diseases because of their complement of sex chromosomes. 7. The completion of the human genome charted the sequence of A, T, C and G in Homo sapiens. The results of this study has given us the following knowledge; the number of genes humans have, what each gene does, and how behaviors are encoded in our genes. 8. Humans are in the mammal Class and in the primate Order. 9. Humans are unique in their physical and behavioral features as compared to other primates. 10. Human variation can be easily categorized and classified. All scientists agree that there are only two sexes in the species Homo sapiens and that humans can be divided into races. 11. Early hominins, like Lucy (an Australopithecus afarensis), co-existed with dinosaurs. 12. Neanderthals co-existed and interbred with early modern Homo sapiens 13. The oldest “human-like ancestors” in the fossil record are some 4.5 million years and they are considered “human-like” (instead of ape-like) because of their big brains 14. Forensic anthropologists can gain insights into the lifestyle, sex, and approximate age an individual was when they died by examining skeletal remains. 15. Humans, whales and dogs are all mammals and they all share the same basic body plan in their limbs. 16. The creation/evolution debate or intelligent design/evolution debate is ongoing in science. Scientists have been debating the validity of evolutionary theory since Darwin’s time with no resolution in sight. 17. All Christian churches and Christian theologians state that you cannot be a good Christian and believe in evolution. 18. Since the persecution of Galileo, science, politics and religion have pretty much stayed in their own separate spheres and there has not been a lot of conflict. 19. Evolutionary theory can explain the origin of life on earth. 20. Evolution is only a theory (and therefore not a fact). What Happened to the Dinosaurs? In “Sex, Drugs, Disasters, and the Extinction of the Dinosaurs,” Stephen Jay Gould puts forth three explanations from scientists to explain the demise of the dinosaurs: sex, drugs, and disaster. Your Assignment is to read the following explanations as to the demise of the dinosaurs. For each explanation; 1) state whether or not you think it constitutes a valid scientific hypotheses to explain the demise of the dinosaurs, 2) specifically review at least 4 aspects of each hypothesis and analyze what can be tested and what can’t be tested, give your data and reasoning for each aspect (as to why you think it is or isn’t testable). Lastly, determine which explanation you think is the most likely explanation for the demise of the dinosaurs. Make sure to have a rationale for all your answers. The dinosaurs died off during a mass extinction event some 65 million years ago. The dinosaurs, along with thousands of marine animals, and ocean plankton died off relatively quickly. The cause of this mass extinction event is the still the subject of some debate. The following have all been put forth at various times to explain the demise of the dinosaurs. Sex: In the 1940’s a study was conducted on alligators to determine their temperature tolerance. It was found that small alligators heated up and cooled down quickly and larger alligators heated up and cooled down more slowly (a function of size to surface area). The researchers speculated that dinosaurs lived in a time period where they lived close to their optimal temperature range. It is known that a slight warming trend occurred around the time the dinosaurs died off. The hypothesis is that the dinosaurs warmed up, not enough to kill them outright, but enough to sterilize them. The testicles of male mammals often function within a narrow temperature range. It is speculated that the slight increase in temperature sterilized the male dinosaurs and caused the extinction of the dinosaurs. Drugs: It is known that flowering plants first evolved toward the end of the dinosaur’s reign. Many of these plants contain psychoactive agents that can be very harmful to animals. Mammals today generally don’t eat these flowers because of their bitter taste and they also have livers that work to eliminate the toxic nature of the plants. The hypothesis is that the dinosaurs could not taste the bitterness that is present in these psychoactive plants, nor were their livers built to allow them to detoxify the plant and render it less devastating to them. The conclusion is that dinosaurs ingested the plants and then died of massive drug overdoses. Disaster: There is a site in the Yucatan where a large comet hit the earth approximately 65 million year ago. The hypothesis is that as a result of this comet hitting the earth there was the formation of a huge, worldwide dust cloud, which blocked sunlight, suppressed photosynthesis and drastically lowered worldwide temperatures. We do know that impacts or volcanic eruptions will affect worldwide weather patterns for years after the event. This hypothesis states that the resulting changes in temperature and available sunlight caused the dinosaurs and a host of other creatures to go extinct. What are the key things that you learned from this assignment? Note the following areas; 1) what can we learn with science? 2) how does science work? 3) what can we learn about the past and how can we study the past? 4) what do the terms; fact, hypothesis, and theory mean in science? Darwin and Lamarck Assignment Name______________________________ Which scenario reflects Lamarck’s Hypothesis of Inheritance of Acquired Characteristics and which reflects Darwin’s Theory of Natural Selection? Your assignment is to label each scenario, as either Lamarck’s hypothesis or Darwin’s theory and then to match each numbered key component (listed below) to the appropriate sentence in the scenario. You can use this sheet of paper and underline each relevant sentence and then put the appropriate number next to it. General information for both scenario’s: Two species of birds exist on Daphne Major island in the Galapagos Islands. The cactus finch’s which eat cactus and the medium ground finch’s which eat seeds. The beaks of the finches are instrumental in their ability to get food. The size and shape of the finch’s beak determines what food they are able to eat. The cactus finch’s beak allows them to get the nectar out of cactus flowers and the medium ground finch’s beak allows them to crack and eat seeds. Scenario #1 ________________________________________ All of the medium ground finches are very similar in their beak size and shape. A drought hits the island and there is no rain for 550 days. Most all of the smaller seeds that the medium ground finches eat are consumed and the medium ground finches start dying off. The only seeds left are quite large and hard. Some of the medium ground finches are able to change their beak size and adapt to the changing environment. These finches adapt and change their beaks to be able to crack the only seeds that are left in the environment, large, hard seeds. The finches that are able to change their beaks are able to survive the change in their food source and live to produce offspring. The offspring of the surviving finches are born with the larger beaks that their parents developed in their lifetime. The population of medium ground finches is now different, it has evolved. The finches now have larger beaks and are able to eat larger and harder seeds. Scenario #2 _____________________________________ The population of medium ground finches is highly variable in their individual beak size and shape. Some of the finches have smaller, shorter, weaker beaks and others have larger, deeper, stronger beaks. A drought hits the island and there is no rain for 550 days. There is now a limited supply of seeds on the island. Fairly quickly all of the smaller, easier to crack seeds are eaten. The finches that have smaller, shorter beaks go hungry and start to die off. The medium ground finches with larger beaks are able to crack the larger, harder seeds, they live longer and reproduce offspring. The offspring inherit their parents larger beaks. The population of medium ground finches is now different. Overall a majority of the medium ground finches now have larger, deeper beaks and there are very few finches with smaller, shorter beaks. Components of Lamarcks hypothesis (put the number next to the appropriate sentence) 1. Environments change 2. Individuals within a species are similar in the traits that they possess 3. Individuals bodies change in response to environmental change, variation is created during an individuals lifetime 4. Variation created within an individuals lifetime is inherited by their offspring Components of Darwin’s theory (put the number next to the appropriate sentence) 1. Variation exists (in traits, among individuals within a species) 2. Competition exists 3. Environment selects desirable traits, as evidenced by fitness (differential reproductive success) 4. Traits are inherited by offspring 5. Environments change 6. Populations evolve over time 1. What is the key trait of selection among the finches? 2. What are the finches competing over? 3. Is the competition within or between species? Protein Synthesis Assignment Name:______________________ Protein synthesis is the process by which the genetic code puts together proteins in the cell. DNA, residing in the ___________________of the cell contains the blueprint for each specific protein. The four letters or “bases” in the DNA “alphabet” (__________________, _________________, _______________, ___________________) combine in various sequences and quantities to form “words” or _____________. Codons are made up of three “letters” or ______________________ (A, T, C, G) and they form amino acids. Each amino acid is made up of three letters. There are ____________different amino acids which combine in various sequences and quantities to formulate the hundreds of thousands of _______________ that make up human beings. The genetic code is redundant in that each amino acid can be coded for in more than one way (e.g. lysine can be coded for by TTT or TTC). Hemoglobin is a protein made up of two chains of amino acids. A mutation occasionally occurs in one of the bases of the second amino acid chain of hemoglobin. This mutation leads of one of the bases (A, T, C, or G) results in the formation of an abnormal protein. Individuals that have this abnormal protein have a condition called sickle-cell anemia. Sickle-cell anemia results in the red blood cells becoming distorted and rigid (sickle shaped) and small clots are formed which deprive the cells of oxygen. Individuals with sicklecell anemia are often ill and before modern medicine often didn’t live to reproduce. Below are the first twelve amino acids that make up the second chain in the hemoglobin molecule. The mutation that causes sickle cell resides in this part of the protein. Below is the sequence of amino acids for normal hemoglobin (each amino acid is indicated by the first three letters of its name): VAL-HIS-LEU-THR-PRO-GLU-GLU-LYS-SER-ALA-VAL-THR Assume you are a researcher studying sickle-cell anemia. You have been given two unlabeled samples of DNA sequences. One is from a healthy individual, and one is from an individual with sickle-cell anemia. Using the table of amino acids (below) and the sequence of amino acids for normal hemoglobin (above), determine which strand is normal and which codes for the abnormal hemoglobin. (HINT: Remember that a codon is a series of three nucleotide bases that code for a particular amino acid). Leucine: AAT, AAC, GAG, GAC Serine: AGA, AGG, AGT, AGC Alanine: CGG, CGA, CGG, CGT Proline: GGA, GGG, GGT, GGC Valine: CAT, CAG, CAA, CAC Glutamic Acid: CTT, CTC Lyseine: TTT, TTC Histidine: GTA, GTG Threnine: TGA, TGG, TGT, TGC DNA Sequences 1. Individual A: C A T G T A A A T T G A G G A C T T C T T T T T A G A C G G C A T T G A Amino acids: _____________________________________________________________________ 2. Individual B: C A T G T A A A T T G A G G A C A T C T T T T T A G A C G G C A T T G A Amino acids: _____________________________________________________________________ 3. Who has sickle-cell anemia? ________________ 4. How did you make this determination? ____________________________________________________ Genetics Assignment (Punnett squares) (Print) Name:___________________________ Genetics Problems: Use punnett squares to answer the problems below. Answer each question completely using percentages to show the probabilities. 1. Cystic Fibrosis is inherited as a recessive disorder. Individuals recessive for the disorder experience excess mucus production, and respiratory problems/failure. If a female (heterozygous) mates with a male (homozygous dominant) what is the probability: a) their 1st child will have the condition _____________? b) their 1st child will be a carrier _____________? 2. Albinism (little or no pigment in skin, hair, eyes) is inherited as a recessive condition. If an albino male mates with a female who is not an albino, but is a carrier what is the probability: a) their 1st child will be albino _____________? b) their 2nd child will be an albino _________? 3. Predicting Offspring/ ABO Blood System: The blood types in the ABO system are determined by three alleles. A and B are codominant alleles, and O is recessive. In the problems below you have the phenotype of the parents. Do a punnett square for each problem and show the possible genotypes for their offspring. a. B (heterozygous) & A (homozygous) b. O & AB c. In a recent court case, a man of blood type A was accused of fathering a child of blood type B. The mother was blood type AB. Could this man have been the father _____________ ? What would his genotype have to be for him to be the father ____________________? Page Two of Genetics Homework (STAPLE!) The following problems are in regards to traits that are sex-linked. 4. Hemophilia is inherited as an X-linked recessive. If a male who is a hemophiliac marries a female who is not afflicted (and not a carrier) what is the probability they will have a son who is a hemophiliac ______? What is the probability they will have a daughter who is a hemophiliac ________? 5. Tooth enamel: A form of defective tooth enamel which leads to brown teeth appears to be inherited as an X-linked dominant trait. Determine the probability of a son having the defect and then determine the probability a daughter will have the defect in the following cases: a) non-afflicted female & affected male, b) affected female (heterozygous) & non-afflicted male. Answer the following questions in your OWN words 6. What is represented on the outside of the punnett square? __________________________________ _____________________________________________________________________________________ 7. What is represented on the inside of the punnet square? ______________________________________ ______________________________________________________________________________________ 8. Do problems 1-3 reflect traits that reside on an autosome or on a sex chromosome? ______________ How do you know? ______________________________________________________________________________________ 9. How many letters are in the DNA alphabet? ________________________________________________ 10. How many “words” (or amino acids) are in the DNA language? ________________________________ 11. What happens during meiosis to the parent’s genetic material? ________________________________ 12. Why are most sex-linked traits on the X chromosome? ______________________________________ 13. What is a codon?____________________________________________________________________ 14. What is an allele? ___________________________________________________________________ 15. Does the environment play a role in the expression of polygenic traits? _________. Give an example of a polygenic trait ______________________________________________________________________ This assignment will be completed in class. Processes of Evolution Problems 1. Physical anthropologist Eva Hernandez visits the Yamomamo in Venezuela and finds that only 3 individuals in a small village of 85 people have blood type A. Her grandson, Alberto Hernandez, returns 45 years later and finds that no one in the village has type A blood. Which process of evolution is likely affecting this population? 2. The allele that causes an altered form of hemoglobin occurs in all human populations as a result of mutation. Individuals who have one allele for this condition have an increased resistance to malaria. Individuals with two alleles for this condition have significant medical problems and die young. This allele has been found in high numbers in certain populations in West Africa, Southeast Asia and Greece. Why would this allele be in such high numbers in certain populations? 3. In 1959 Daniel Yuh set up a long term study of cataloging the blood types of a group of huntergatherers in the Brazilian rainforest. In 1959 he found there were no individuals with blood type B. Three generations later, after this group had begun exchanging mating partners with another group, there were several members with blood type B. Which process of evolution is likely affecting this population? 4. Britain’s Queen Victoria was a carrier for the allele that causes hemophilia and she passed this allele on to some of her descendants. However, there is absolutely no evidence of anyone in Queen Victoria’s ancestry having hemophilia. What is the most likely explanation for her possessing the hemophilia allele? Which process of evolution likely led to some of her descendents having this allele? 5. The inhabitants of the island Tristan de Cunha are all descended from one indigenous family and a few sailors. The incidence of a rare eye disorder is much higher in these islanders than in other human populations. Presumably, at least one of the original island settlers carried the allele of the trait. The disorder has an abnormally high frequency in this small population because many can trace descent from this one member of a small group of colonists. Which process of evolution likely affected this population in regards to this trait?