1 Which explanation best summarizes why scientists have been unable to find the conclusive location of the root for the three main branches of the tree of life A There are too few genes in common among the branches to resolve the relationships among them B There are plenty of genes in common but to date there have not been analyses of nucleotide sequence patterns in enough of them to resolve those relationships C There is plenty of information on nucleotide sequences but different sets of genes support different locations for the placement of the root 2 Which of the following lines of evidence can be used to identify the signature of lateral gene transfer A A signed copy of a receipt dated from at least 2 billion years ago B The nucleotide sequence of a particular gene places a taxon in a completely different clade than do the trees derived from sequences of several other genes C Relics of transposase or viral insertion sequence D Answers B and C above E None of the above lateral gene transfers can only be identified from direct observation of plasmid conjugation 3 Which of the following evidence supports the hypothesis for the endosymbiotic origin of eukaryotes A DNA synthesis in the organelles of eukaryotic cells is continuous and not step like with distinct phases G1 G2 etc as in the nuclei of eukaryotic cells B Organelles of eukaryotic cells are enclosed by double membranes and some structures in some cells are enclosed by even more layers of membranes C The organelles of eukaryotic cells have circular chromosomes of their own with supercoiled DNA and an absence of chromosomal proteins D There is very high similarity in the nucleotide sequences of certain genes found both in organelles like chloroplasts and the nucleus of some prokaryotic organisms E All of the above 4 When we say that the patterns of species or genus diversity within clades are bottom heavy we mean A Most clades need more exercise B Clades tend to diversify to a greater extent early in their evolutionary history that is with a burst of new taxa soon after the clade first appears in the fossil record C Clades tend to diversity to a greater extent later in their evolutionary history that is with a burst of new taxa appearing shortly before the entire clade appears to go extinct D There has been extensive extinction events among the taxa within the clade such that the apical taxa represent a distinct subset of all of the taxa that belong in the clade 5 Scientists have debated if climate change alone caused the extinction of the Pleistocene megafauna or whether human hunting contributed to those extinctions Which line of evidence is consistent with or supports the hypothesis that humans contributed to the megafaunal extinctions in other words that CLIMATE CHANGE ALONE is not likely the correct explanation A Extinctions were selective with respect to body size and reproductive rate larger species with slower reproductive rates were more likely to go extinct B The rate of climate change in this period was not unusual compared to rates of change in other periods that did not have mass extinctions C The megafauna of New Zealand did not disappear until humans colonized the islands despite experiencing the same climate change as animals at comparably high latitudes elsewhere D Answers A and B but not C E Answers B and C but not A 6 Which statement describes best the relationships among repeated asteroid impacts and periodic pulses of extinction pulses meaning a marked short term elevation of extinction rate A There is no consistent relationship among all asteroid impacts and pulses of extinction B There have been asteroid impacts without co occurring pulses of extinctions but every pulse of extinction is associated with an asteroid impact C There have been pulses of extinction without asteroid impacts but every asteroid impact is associated with a pulse of extinction D Asteroid impacts and pulses of extinctions are almost perfectly associated indicating that asteroid impacts are a likely trigger of nearly all pulses of extinction 7 The notion of continental drift is formally a hypothesis because A There is no evidence either supporting or refuting it B Every explanation in science is deemed a hypothesis even when supported by evidence because in principle new evidence could emerge that would falsify it C Hypothesis is a nicer more dignified term than crazy notion D It can never be tested and thus never falsified 8 Punctuated equilibrium refers to A Stability in the usage patterns of commas periods quote marks exclamation points B The apparent constancy of biodiversity over time whether measured as number of genera or families or orders C The historical pattern in which we see characters changing abruptly with little change over time within any single line of descent and most changes in characters associated in time with the formation of new taxa or new lines of descent 9 Bateman s Principle is A Whichever gender has the steeper relationship between reproductive success and mating success will be the gender in which sexual selection is stronger B Whichever gender invests more per gamete is likely to be the limiting resource for reproduction and will be the object of sexual selection in the other gender C Sexual selection among males always occurs through actual or ritual combat among males that is intrasexual selection D One can always count on males to behave badly 10 For kin selection to be operating which of the following conditions is both necessary meaning required AND sufficient meaning no other condition is necessary A Individuals must live in a group with related individuals B Individuals within any group that includes that individual s relatives among other individuals must behave altruistically C An individual must completely sacrifice its own fitness for the fitness of nearby relatives D An individual s behavior must be directed toward its relatives and enhance their fitness more than any effect on unrelated individuals 12 Looking at the above chart which of the following is the best explanation for the differences between the rate of change in nonsynonymous compared to synonymous sites A Most mutations at synonymous sites increase overall fitness and are favored by selection whereas most mutations at nonsynonmous sites are deleterious and are selected against B Mutations in synonymous sites accumulate because most if not all are neutral while most mutations at nonsynonymous sites are removed by purifying