Study Guide Final Exam – EVOLUTIONARY ECOLOGY Previous material: Major evolutionary transitions (Chapter 2) Major ecological transitions (Chapter 3) Life history evolution (Chapter 4) Sex allocation (Chapter 5) Dispersal evolution (Chapter 6) Adaptive behavior and plasticity (Chapter 7) Generalization vs Speciation (Chapter 9) Focus on new material (Chapter 10-16) Antagonism vs. cooperation (Chapter 10) Types of Symbiosis 1. Increasing human crowding should lead to the evolution of ____ virulence in our pathogens (see figure above) A. Increasing B. Decreasing C. No change in 2. According to Mayhew, evolution of new pathogen strains within hosts (e.g. in patient 7) should lead to _____ virulence; pathogen evolution is less likely in patient ____. A. Increasing; 1 B. Increasing; 6 C. Decreasing; 1 D. Decreasing; 6 E. No effect on; 1-10 3. According to the model of Anderson & May (1982), a pathogen’s fitness is higher with decreasing A. reproduction within hosts B. host density C. survival of hosts D. host recovery E. numbers of unaffected hosts 4. According to Mayhew, a pathogen should evolve lower virulence when it A. Is spread by a seasonal vector B. Is in an increasingly rare host C. Is horizontally (vs. vertically) transmitted D. (A) and (B) E. (B) and (C) 5. The yucca moth-yucca mutualism is likely maintained by all of the following except A. Vertical transmission of chloroplasts B. Benefit of pollination C. Lack of alternative pollinators D. Production of excess seeds E. Ability to abort failed fruits 6. According to the background reading, when Eciton burchellii army ants form an aggregation while swarming, it always indicates capture of a prey item A. True B. False C. It is not discussed 7. The most useful hypothesis about army ants and ant birds would be (refer to Fox 2014): A. Antbirds affect the foraging of army ants. B. Army ants will capture more prey when antbirds are present, compared to when antbirds are not present. C. Antbirds are parasitic on army ants, because the antbirds steal some of the ants’ prey. D. Ho: antbirds do not affect army ants. Ha: antbirds are mutualists with army ants. E. Army ant foraging concentrates nutrients in the bivouac area, increases herbivory by reducing predator populations, and attracts antbirds, which are commensal with the ants because they take insignificant biomass of prey. Coevolution (Chapter 11) Coevolution models Variables: • Speciation/radiation, anagenesis, or extinction • Number and stability of interacting species • Speed and direction of changes in traits • Degree of antagonism Aphids and Buchnera • Obligate symbiont with aphids • In bacteriocytes • Synthesize amino acids 1. Leaf cutting ants and their garden fungi are only found together (obligate mutualism). This symbiosis is an example of ________ coevolution. A. Diversifying B. Escape-and- radiation C. Arms race D. Alternation E. Mutual dependence 2. Cameron Currie (“the ant man”) discovered that species of leaf cutting ants, their garden fungi, and parasitic fungal “weeds” have all coevolved. Noting the host switching especially in the lower attines, the co-evolution of garden and weed fungi probably shows ____ traits and _____ antagonism. A. Stable; increasing B. Stable; decreasing C. Dynamic; increasing D. Dynamic; decreasing 3. Difference between symbiosis & coevolution? 4. Explain, and give an example of, how the mode of coevolution can drive the: – Number of interacting species – Dynamics of species richness – Temporal dynamics of traits – Dynamics of antagonism 5. What is a geographic mosaic? 6. This is an example of coevolution in a geographic mosaic A. True B. False 7. This example of coevolution involves ______, where the species involved are interacting _____. A. cladogenesis; antagonistically B. cladogenesis; cooperatively C. cladogenesis; indirectly D. anagenesis; antagonistically E. anagenesis; cooperatively Speciation (Chapter 12) • • • • Origin of life Symbiosis Hybridization Lineage splitting Hybridization • Homoploid (diploid) • Polyploid 1. The traditional view was that hybridization between species, even closely-related ones, rarely produces viable offspring, because 1) After genetic differentiation, homology (e.g. synapsis in meiosis) _____ function between the two genomes 2) Even if hybrids did form, they would have _____ fitness than/as their parents 3) The theorists were not botanists! A. B. C. D. E. Would; higher Would; lower Would not; higher Would not; lower Might; the same 2. As shown here in this more recent view, hybrid species can sometimes form because A. Diploid gametes can mate to give polyploid hybrids, which may open new niches B. Recombination can allow novel adaptive variation C. The adaptive landscape can change temporally D. (A) and (B) E. (B) and (C) Why is hybrid speciation more common in plants? 3. Hybrid species are A. B. C. D. E. always intermediate in phenotype between the parents always less fit than the parents, except in anomalous years less variable in phenotype, compared to the parents sometimes able to originate in allopatry probably much more common than had been previously thought Lineage Splitting 1. According to Mayhew, do the different modes of lineage splitting have the same pattern of range overlap (as shown below) later on? A. Yes B. No C. Mayhew doesn’t say 2. If speciation occurs between adjacent populations in Ensatina, it would be ______ and would involve _____ populations. A. Allopatric; big B. Allopatric; local C. Parapatric; big D. Peripatric; local E. Sympatric; local 3. Reproductive isolation in sympatric speciation would be least likely to occur by: A. B. C. D. E. a host switch, for a parasite a change from spring to summer flowering, for a plant a new mating preference, for an animal a switch to nocturnal flowering, for a diurnal blooming plant a change in age of maturity, for an animal Extinction (Chapter 13) 1. According to Kunin and Schmida (1997), “Most ecological generalizations stem from the study of ____ organisms, but most species are ____. [Don’t look up the paper!] A. Common; common C. Rare; common B. Common; rare D. Rare; rare Rank-abundance curve of healthy human lung microbiome 2. Rare plant species tend to have ____ flowers than common species if outcrossing, and ____ flowers than common species if selfing. A. Larger; larger B. Larger; smaller C. Smaller; larger D. Smaller; smaller 3. According to Mayhew, curve (a) represents likelihood of extinction from ______ causes. A. Environmental, deterministic B. Environmental, stochastic C. Demographic, deterministic D. Demographic, stochastic What is the Allee effect? 4. Which curve or part of a curve (A-D, or E) illustrates the Allee effect? • • • Metapopulation Dynamics Local population effects Fragmentation – adaptation or extinction? Environmental and demographic causes of extinction: Stochastic vs. deterministic? Genetic causes of extinction—What increases the likelihood of: • • • Introgression Inbreeding depression Genetic drift. See: http://www.nature.com/scitable/topicpage/genetic-drift-and-effective-population-size-772523 5. Which is evidence for the extinction of Neanderthals by a stochastic mechanism? A. Anatomically, Neanderthals were slower runners than more recently arrived humans. B. A series of volcanic eruptions 40 kya correlates with less plant pollen in sediments. C. Neanderthal females may have participated in hunting. D. Modern Europeans have 1-4% Neanderthal DNA. E. Neanderthal populations became fragmented. Macroecology (Chapter 15) 1. Body size is shown on the x-axis and species richness is on the y-axis. A greater frequency of small body size caused by small ancestral body size and (mostly) stabilizing selection on body size is shown by figure 2. Phylogenies are shown with extant taxa at their respective latitudes. Which phylogeny (A-D) shows a tropical origin, migration to the temperate zones at several times in its evolutionary history, but a greater speciation rate in the tropics? 3. What is the difference between the two types of macroecological patterns? Give examples • Frequency distributions • Associations of variables 4. What is the difference between the two types of explanations for macroecological patterns? Give examples. Recall climate change hypotheses from AAS (2010). • Proximate processes • Ultimate causes Sustainability (P Read 2009, Caldeira 2013, Burger 2012) Macroevolution (Chapter 14) Chapter 16 (short) • • • • • • • Macro- vs. micro-evolution Clade Diversity Disparity Morphospace Tree shape –See http://ib.berkeley.edu/courses/ib200b/lect/ib200b_lect16_Nat_Hallinan_Lindberg_tree_shape2.pdf Adaptive radiation According to Mayhew, the species richness of a clade is influenced by all of the following except A. Speciation rate B. Extinction rate C. How recently the clade evolved D. Binary vs. continuous morphological traits E. Acceleration of species replacement in mass extinctions Macroevolution concepts • • • Evolutionary histories of major clades – Diversity (clade width) – Disparity (clade number) Tree dynamics (shape) – Topology – Branch lengths Evolution of disparity Questions? • How do we measure macroevolution? • Temporal trends – Marine vs. terrestrial Hypothesis: • • • • Morphological & physiological innovation More efficiency → optimization Narrowing to fewer, best designs But diversity increases! Explain! – Effect of extinctions? • Spatial trends • Trends across taxa—what promotes diversification? Which tree shapes might be caused by: 1) Successive key evolutionary innovations? 2) Opening of a new niche (e.g. land or phagotropy)? 3) Environmental change (opportunity)? Evolution of animal disparity Which hypothesis (A-D) is most supported here? orE. It is unclear, because the tree shape is uncertain Phylogeny of the Cambrian explosion How do evolution & ecology interact? Big evolution + big ecology! (Chapter 16) 1. According to this study, clades of generalists, on average, ____ last longer than specialists, and there was ____ overlap of lineage duration. A. Did; much B. Did; little C. Did not; much D. Did not; little 2. Mass extinction caused by the K-T asteroid impact is supported by the fossil record of: A, B, C, or D below (choose 1) or- E. All of them Summary