BIO 370 1st EditionExam # 2 Study Guide Lectures: 8 - 13BIO370 Evolution Exam 2 Study GuideThe Evolution of Sex (Lecture #8)- Be able to define sex in an evolutionary standpoint.o Exchange of genetic material Outcrossing/outbreeding: unrelated material introduced into germ line (heterozygous typically) Inbreeding: pertaining to closely related species (homozygosity) Recombination (variation between offspring)- Crossing-over- Independent assortment- Differentiate between sexual and asexual reproduction.o Sexual Majority of species reproduce in this way Longer persistence Diversification Elimination of deleterious genes over timeo Asexual Short-lived, recent Few ancient lineages- Ex. bdelloid rotifers (40 million years) – only females exist Sporadic taxonomic distribution Two times the reproductive rateo Some species switch between the types of reproduction. Cyclic asexuality: one type is more advantageous at a certain time- Know the advantages and disadvantages of sex.o Advantages Ability to rid deleterious mutations Favorable mutations (faster evolution)o Disadvantages Cost of meiosis vs mitosis- 50% disadvantage- Cost of producing males- Gene vs. parent view Time and energy, finding sexual partner STDs “poisoning genes” Interruption of co-adapted geneso Yes, the advantages outweigh the disadvantages. Sex is maintained throughout many different species.- What are plausible reasons for the origin of sex?o Mechanism of DNA repair as an example.o May be different from maintenance of sex.- What is the original inequality?o More investment from female, typically, to offspringo Mating effort typically greater in males- Isogamy vs. Anisogamy- Know about intra and inter-sexual selection.o Male-male competitiono Female choice- Be familiar with some examples of sex-role reversal.o Males with higher parental investmento Females with higher mating efforto Female-female competitiono Male choiceSexual Selection (Lecture #9)- Develop a further understanding of parental investment as described from the previous lecture.o Original inequalityo Reproductive vs. mating efforto Intra vs. inter-sexual selection- Be aware of these observations.o Sexual size dimorphism between males and femaleso Males are typically the “elaborate sex”o Elaborate traits usually reduce survival- What are some clues to explain sexual dimorphism?o The elaborate trait limited to one sex Ex. antler in male deero Expression of traits at sexual maturityo Traits during breeding seasons- Define sexual selection and natural selection.o Sexual selection: reproduction due to variation of mates’ obtained as well as specific mate choice A type of natural selectiono Natural selection: reproduction due to variation of heritable traits- What are the components of fitness?o Gametic/fecundityo Compatibilityo Viabilityo Sexual selection- Know the types of male-male competition.o Direct combat Males fighting for access to mates for inseminationo Sperm competition Males compete and giving sperm packages to females Ex. damselflies- He attaches to her neck, she morphs around for her abdomen to connect to him, he clears her out, and then inseminates.o Infanticide Females become receptive when there are no cubs around.- Female choice (inter-sexual)o Direct selection Affects female survival and fecundity Mates chosen that can provide resources Population is stableo Indirect selection Does not affect female survival and fecundity Preference with the male trait Population is unstable Runaway process Know about the Fisherian runaway model and the good genes modelo Sensory exploitation model of sexual selectionAdaptation/Fitness and Unit of Selection (Lecture #10 - 11)- What is the definition of adaptation? What is its significance?o Prevalent and maintained feature used as a selective advantage for improvemento “good fit” serves to solve problems- How can you develop a better understanding of adaptation?o By knowing/analyzing: Single vs. multiple functions of traits Original vs. current functions Adaptations vs. byproducts- Identifying adaptations and distinguishing them from byproducts can be done. How?o Functional analysiso Optimality analysis- Which units of organization are able to have adaptations?o Those with: Heredity Heritability- What is a unit of selection?o Heritability is shown and frequency is maneuvered by natural selection- Distinguish upon the two meanings of the unit of selection.o Replicator Replication/inheritance The gene Immortal Enhanced persistenceo Vehicle Interaction The individual Not immortal Enhanced survival/reproductiono Vehicles built by replicators that travel- How is natural selection typically viewed?o Acting on individualso Selecting for genes- When is this typical view of natural selection not seen?o Selection acting on genes, against individualo Selection acting on organizational structureso Some organization structures not relevant to natural selection- Know about the selfish gene view and the multi-level selection view.- What are the limits of adaptation?o Phenotypes are compromiseso Developmental and genetic constraintso Time laggingLife History Evolution (Lecture #12)- Define life history.o Timing/allocation of resources used for – Growth  Reproduction Maintenance and repairo Affecting future generations- What is the evidence that selection does shape life history traits?o Viewing artificial selection in different stages of reproduction Effects on longevity Drosophilao Comparing related species- Know about parental survival vs. parental reproduction.- Know about offspring survival vs. parental reproduction.- Be able to determine the whys and why nots of the 50:50 sex ratio.o Why? Fisher’s model- Returns-per-investment Numerical vs. investment sex ratioo Why not? Assumptions of Fisher’s model- Violations cause a deviationo Competition between offspring of the sexeso Offspring of one sex helps more than the othero Fitness of one sex becomes greaterEvolutionary Medicine (Lecture #13)- What else is evolutionary medicine known as?o Darwinian medicine- What is evolutionary medicine and what is its significance?o Branch of applied evolutiono Used to understanding disease and their processeso Design effective treatments of these diseaseso Prevention of resistance evolution- Aging can be used synonymously with what term?o