Name_____________________
Undergrad
BZ508 - Exam 2 – Fall 05
50 pts Total
(1 pt each) Match the letter from THE LIST with the following statements:
n 1. An example of a fish-tetrapod evolutionary intermediate
g 2. An example of a vestigial structure
e 3. A type of heterochrony
a 4. Primary rock type in which fossils are found
p 5. Estimated time of divergence for chimp-human ancestor
h 6. Model for the origin of life
b 7. Dr. Voss’s favorite primate group
c/l 8. Homo sapiens closest living relative
u 9. Approximate time of the big bang
s/t 10. Approximate time of earth’s origin
r 11. Approximate time of the first eukaryotic life form
j 12. Catalytic ribonucleic acid
o 14. Paleozoic Era
I 15. Rocks used for radiometric dating
THE LIST
a. sedimentary
h. Haldane-Operin
b. prosimian (lemurs)
i. igneous
c. chimpanzee
j. ribozyme
d. retrograde
k. mitochondria
e. paedomorphosis
l. chimpanzee
f. ambulocetus
m. gorilla
g. human coccyx
n. icthyostega
o. ~0.5 bya
p. ~5 mya
q. ~10 bya
r. ~2 bya
s. ~4 bya
t. ~5 bya
u. ~14 bya
(1 pt each) Multiple Choice
1. Natural selection operates at what level?
a. individual
c. population
b. species
d. genus
2. Which of the following is not associated with an adaptive radiation?
a. multiple related species adapted to different niches
b. geographic clustering of similar species
c. gradual evolution and adaptation over a long period of time
d. rapid initial evolution of lineages
3. If the Law of Succession applied to human evolution, which of the hypotheses below
would be supported?
a. multiregionalism
c. plate techtonics
b. out of Africa
d. out of Versailles
4. True or False. Some molecular mechanisms underlying eye development in fruit flies
and humans are homologous.
a. True
b. False
5. The idea that “Ontogeny Recapitulates Phylogeny” is best explained as:
a. Dissociation of the relative timing of events during development
b. Terminal addition of characteristics onto an ancestral developmental program
c. Embryos pass through stages of development that chronicle adult ancestral
forms
d. Pattern generated by an intelligent designer
6. What are the two major types of heterochrony?
a. paedomorphosis and stasis
b. paedomorphosis and macromutation
c. peramorphosis and stasis
d. paedomorphosis and paedomorphosis
7. What did Dr. Voss’s research show about metamorphic timing in salamanders?
a. variation in metamorphic timing is all environmentally based
b. salamanders metamorphose earlier when they eat other salamanders
c. the same gene contributes to metamorphic timing and paedomorphosis
d. salamanders die if metamorphosis happens after a pond dries up
8. The strata of the Grand Canyon contains a geological record of
a. 1,000 years
c. 1,000,000 years
b. 10,000 years
d. 1,000,000,000 years
9. What feature is associated with the evolution of primates?
a. stereoscopic vision
c. decreased body size
b. elaboration of olfactory structures
d. short, stubby digits
10. True or False. Fossil evidence suggests that up to 15 different species of hominids
coexisted in Africa approximately 3 million years ago.
a. True
b. False
11. Which of the following early homonids probably walked upright?
a. Homo erectus
c. Australapithicus afarensis
b. Homo neanderthalensis
d. all of the above
12. The Out of Africa hypothesis predicts
a. greater morphological similarity between modern humans from different world
regions than between modern and archaic humans within regions
b. more molecular level differences among modern, non-African populations than
among African populations
c. African mitochondrial haplotypes in the most recently evolved branches of the
mitochondrial gene tree
d. hybridization between Homo sapiens and Homo neanderthalensis
13. The Out of Africa hypothesis predicts that modern Homo sapiens migrated from
Africa
a. > 1,000,000 years ago
c. 1,000 years ago
b. ~500,000 years ago
d. ~100,000 years ago
14. The mt DNA data collected from Homo neanderthalensis suggests that
a. humans and neandertals exchanged genes
b. neandertals are an evolutionary separate lineage from modern humans
c. neandertals could speak and make cave art
d. neandertals had an unusual genome structure
15. True or False. Multiple molecular datasets support the Out of Africa hypothesis and
not the Multiregionalism hypothesis.
a. True
b. False
16. Which of the following is evidence in favor of the idea of an RNA world preceding
the evolution of DNA based life?
a. ribozymes
b. ATP
c. mRNA
d. all of the above
17. Which of the following protein-like tasks are not accomplishable by an RNA
molecule?
a. phosporylation
b. peptide-bond formation
c. RNA dependent replication
d. carbon-carbon bond formation
18. What was the cenancestor (common ancestor of life on earth) like?
a. possessed DNA but did not make proteins
b. possessed DNA but was not cellular
c. possessed DNA and mitochondria
d. possessed DNA and proteins
19. The panspermia hypothesis suggests that
a. only human life is of alien origin on earth
b. all life on earth evolved from extraterrestrial biomolecules or life forms
c. all life on earth evolved from inorganic comet dust
d. sperm can tolerate re-entry through earth’s atmosphere
20. Why is it difficult to reconstruct the tree of life for all living organisms?
a. there are few characters that are shared among all living forms that have
evolved at a rate that accurately registers phylogenetic history
b. horizontal gene transfer occurs uniquely and frequently among Eukarya taxa
c. the small subunit RNA molecule evolves too rapidly
d. maximum-likelihood analysis is not a suitable method
21. What evidence supports the idea of an RNA world before the origin of cellular life?
a. Tetrahymena has RNA that is catalytic
b. RNA can self-replicate in prokaryotes
c. Mitochondria and chloroplasts have RNA genomes
d. Stanley Miller’s famous reducing atmosphere experiment
22. What results below support the Oparin-Haldane model?
a. adenine nucleotides can be readily made from ammonia and hydrogen cyanide
b. clay is a catalyst for the formation of polynucleotide chains
c. amino acids can be formed from methane, ammonia, hydrogen, and an electric
spark
d. all of the above
23. Which of the following correctly traces the temporal sequence of hominid evolution,
from early to more recent fossils?
a. Australopithecus afarensis, Australopithecus robustus, Ardipethecus ramidus
b. Ardipethecus ramidus, Australopithecus afarensis, Homo erectus
c. Homo habilis, Homo neanderthalensis, Homo erectus
d. Australopithecus robustus, Australopihtecus afarensis, Ardipithecus ramidus
24. Which of the following statements about human evolution is correct?
a. The origin of Homo sapiens dates to 1 million years ago
b. PCR has been used to sample DNA from Homo erectus fossils
c. Species of Australapithecus overlap in time with species of Homo
d. DNA evidence suggests that humans and chimps can still interbreed.
25. What features are associated with Homo evolution?
a. larger body sizes than australopithecines, especially height
b. larger jaw size and jaw musculature than australopithecines
c. bipedalism is unique to Homo (not found among australopithecines)
d. smaller brain cases than australapithecines
Essay (10 points). Please answer one of the following two questions.
1. What are the different processes that yield fossilized remains and explain why
the fossil record is biased?
Permineralization fossils are formed when structures are buried in sediments and
dissolved minerals precipitate out of cells.
Compression and impression fossils form when organic material is buried in
sediments before it decomposes.
Casts and molds form when remains decay after being buried by sediment.
Unaltered remains are preserved sometimes in environments that prevent
decompostion, such as ice, amber, and peat bogs.
The fossil record is biased because most fossils come from lowland or marine
habitats. Most organisms lack mineralized body parts and therefore are not
amendable to fossilization. There is bias because the earth’s geological processes are
operating differentially over space and time; some areas are more likely to yield
fossils than others, and some areas are more likely to result in the destruction of
fossils than others. Thus, there is taxonomic and sampling bias in the fossil record.
Essay (10 points) 2. Describe in detail the evidence supporting the origin of a major
taxonomic group (e.g. amphibia, birds, cetaceans, mammals, humans, etc). I need to
see details concerning the relevant taxonomic groups, time of origin, and relevant
character changes.
Origin of Amphibians:
The first amphibian fossils belonging to the genus Ichthyostega are known from the
Devonian of Greenland. Ichthyostega represents an evolutionary intermediate
lineage between the rhipidistian fishes of the Sarcopterygii (lobe-finned fishes) and
modern amphibians. As evolutionary intermediates, icthyostegids had
characteristics of the rhipidistian fishes (tail fin, braincase, limb bones, dermal skull
bones, lateral line canals, and distribution of teeth), intermediate characteristics
(larger pectoral and pelvic girdles), and amphibian-like characteristics (limbs).
Ichthyostega had many digits and was aquatic; a recent fossil with only 5 digits like
modern amphibians has been recently discovered. The evolution of the amphibia
provides evidence of both mosaic (limbs evolved faster than the dermal bones, for
example) and gradual (limbs are intermediate between lobe-finned fish and modern
amphibians) evolution of morphology.
3. (3 points) What is horizontal gene transfer and how is it detected? Please explain
and perhaps draw a tree.
Horizontal gene transfer is the movement of genetic material between organisms other
than by transmission from parents to offspring. It can be detected using phylogenetic
approaches. For example, if a particular DNA sequence is homoplasious with respect to
all other characteristics supporting a bomb-proof phylogenetic hypothesis, then horizontal
gene transfer may explain the homoplasy.