SBI3U Grade 11 Biology Evolutions Review Questions Evolution Review Questions and answers 1) Outline the contributions of Cuvier, Hutton, Lyell, Buffn, Linnaeus, Wallace,Lamarck, and Malthus. Cuvier: investigated fossils and found layers of different species -Observed that one species is unique to one layer -Suggests that catastrophe occurred and others migrated in -Creator of the Theory of Catastrophism Hutton: said earth is very old -Small changes over time add up to big differences like mountains. Buffon: said species change over time -Introduced ideas about common ancestry through similarities Linnaeus: said that species can be classified through names -Father of Taxonomy Lamarck: said that a mother could “influence” the traits to the child -Giraffe example stretching it’s neck – Theory of Inheritance of Acquired Traits Malthus: said too many are born, but little survive due to limited resources -Supported the idea of natural selection Wallace: sent his ideas about natural selection to Darwin -Made Darwin publish his papers before he does. 2) Outline Lamark’s theory of evolution of “inheritance of acquired characteristics”,and compare it to Darwin’s theory of evolution by natural selection Inheritance of acquired characteristics states that the actions from the traits that the parentsfollow are influenced to the child. A parent giraffe needed to stretch his neck higher to getthe food, and passes that to his child. While natural selection states that the traits that arefavored are kept, while others aren’t. The giraffe with the longer neck will be kept because
they can get food and survive, while the ones with shorter necks will die off. The longer neckone will reproduce, carrying it’s traits to the next generation. 3) Outline the observations of Darwin from his HMS Beagle voyage, which led to histheory. During his voyage to South America, he noticed 2 types of Finches from two different areas.From one, their beaks were short, while just up the hill; the Finches there featured larger,longer beaks. This was because the birds higher up on the hill had to adapt to thevegetation, which were flowers with nutritious parts deep within the pedals of the flower. Thebirds had to adapt their beaks so they can stick into the flowers and retrieve the foods.Those without the traits for a long beak would die and their traits won’t be carried on. 4) State the two ideas that Darwin presented in his book “On the Origin of Species”. The idea of Natural Selection and the idea of common ancestry. 5) State the 5 major points of Darwin’s theory of evolution by natural selection andexplain with examples. -There are more creatures born than can survive -300 Ostrich eggs, most of them eaten by rats before they mature -There are variations in traits -Some Ostriches that can run fast, but some slower -Some traits are more advantageous -Faster Ostriches can run away from predators quicker and therefore be eaten less andadvantageous over slower trait -Advantageous traits -> better chance of survival and reproduce -Those who run away from predators can continue to live, grow, and live somewhere safe forthem to reproduce. -Disadvantageous traits are destroyed -The Ostriches that run slower are eaten by predators 6) Define evolution The change of organisms due to a difference in genetic variation to adapt to the changingearth around them. 7) Explain how evolution is a feature of populations and not individuals Evolution cannot change a person’s genes after it’s been inside a person’s body. Even if youwere a giraffe, and you had a short neck, you neck can’t get longer over your own lifetime. If
you carry the favored gene, then it will be passed onto your children, changing thegenerations after. You yourself cannot change to adapt in your lifetime. 8) Define natural selection. Natural Selection is where the variation that’s favored will be preserved, while those withunfavoured traits will be destroyed. 9) Indicate the importance of variation to natural selection Variation is important to natural selection because it’s variation that triggers evolution. It’s upto the variations that offer some differences between creatures that allow them to have theability to survive the environment. If there were no variation, then they will either all befavored, or not favored, leading to no population or a great population that won’t withstandanything that happens in nature. 10) Define adaptation Any anatomical structure chemical make up or behavior that enables an organism to live init’s environment. 11) Explain evolutionary myths 1. Individuals evolve 1. i. As proven in question 8, it’s not possible 2. Natural selection has a purpose, to increase complexity of things 1. i. Has no purpose, direction, or goal. Not even the survival ofspecies. No indication of progress 3. Evolutions by natural selection produces higher and advanced more humans 1. i. Evolution does not make higher level humans 4. Evolution proves that there is no god 1. i. Evolution does not seek to negate the existence of god 5. Humans are descendants of apes 1. i. Humans aren’t from apes; we share the same commonancestor with apes. Humans also share common ancestry withevery other living thing as well. 12) Describe the importance and results of the industrial melanism and the pepperedmoth lab. Before the industrial revolution, birch trees were white. Peppered moths adapted to that byturning itself white to camouflage with them and not be eaten. During the industrialrevolution, the soot from factories painted the birch trees black. The moths adapted to thatand turn itself black to avoid being seen. After the people realized the mess with the sootthey’ve caused, they began to clean things up, restoring the birch back to their white color. 13) Explain the different forms of evidence for evolution including fossil records,vestigial structures, homologous structures, and analogous structures, embryology,vestigial sequences, and molecular evidence. Fossil Records: shows the structure of the animal preserved from ancient rocks. They can be compared with other generations of the same species to see structural differences.
Vestigial Structures : are structures that are in current generation animals that aren’t currently put to use. This suggests that these organs come from older generations of thatanimal but have evolved to not require them anymore. Homologous structures: are structures that look the same or offer very similar functions across a broad range of species. These suggest that they come from a common ancestor intheir evolutionary past. Analogous Structures: are structures that are similar but these animals aren’t from a common ancestor and suggest a convergent evolution. They’ve grown to have similar traitsby adapting to their own respective environment but happen to result in similar structures. Embryology: almost all species have very similar embryos, which suggest a common ancestry that gave them the same embryos. Vestigial Sequences: sequences of a gene that use to be in use but no longer serve its purpose. It’s been disabled. Suggests common ancestry where this gene used to berequired but not anymore because natural selection has proven that gene not worthy ofcarrying on. Molecular Evidence: Amino acids in body are almost 100% identical. Any differences in Amino acids or DNA sequences are going to tell how closely related these species are. 14) Compare divergent and convergent evolution Divergent evolution is where one species branches off this line and continues. Convergent evolution is where two species that branched off a long time ago that happenedto meet at a similar proximity. They’ve branched off a common ancestor from before, buthave evolved to be two completely different species that aren’t related but have very similargenes. 15) Describe the uses of a cladogram and be able to create one using amino acidsequences Cladograms are diagrams that the relationships between different species based on thenumber of common traits they offer. Each species has more common traits the further inthey go into the cladogram. 16) State the 5 conditions that are required to maintain a non-evolving population First: random mating Second: No natural selection Third: No genetic drift Fourth: No genetic flow Fifth: No mutations
17) State the Hardy-Weinberg Equilibrium Formula p + q = 1 p^2 + 2pq + q^2 = 1 p^2 = number of AA alleles q^2 = number of aa alleles 2pq = number of Aa alleles 18) Explain the term allele frequency and describe how allele frequencies areexpressed for a population. Allele frequencies are the number of times one allele (a or A) appears in a population. Theyare expressed as a percentage. (ie 42% of the entire population have A alleles) 19) Use the Hardy-Weinberg Equilibrium Formula to determine the dominant andrecessive allele frequencies and phenotypic and genotypic frequencies. p^2 = number of AA genotype 2pq = number of Aa genotype q^2 = number of aa genotype p = 1-q = number of A alleles q = 1-p = number of a alleles 20) State and describe the five factors contributing to microevolution which leads todeviations from the Hardy-Equilibrium Assumptions. These include: gene flow,genetic drift (founder effect and bottleneck effect), mutation pressure, naturalselection, and sexual selection. The 5 factors that contribute to micro evolution changes allele frequencies each year whichadds up to major changes over time as macro evolutions. Mutation: changes the DNA of an organism where new alleles add and change allele frequencies, altering the creature. Gene Flow: Gains and reductions in alleles dues to immigration or isolation. Large amounts of alleles leave or one new allele is introduced. Whatever’s isolated or introduced willincrease in allele frequency and essentially take over. Genetic Drift: Some population that’s lost, the alleles that they carry will be lost too, losing genetic diversity Bottlenecks: after disaster, most were killed off. The remaining few traits will reproduce, resulting in a generation with that limited trait remaining.
Founder: When small parts of the population are separated and they reproduce on their own and create a there own allele frequencies and diverge into their own species. Whateverwas dominant in that species will become the dominant allele in that population. Non-Random Mating: Sexual selection where some traits are preferred by girls over another trait, meaning that preferred trait will carry on. Natural Selection: the favored trait ideal for the environment will be carried on while the unfavorable traits will be destroyed. 21) Outline the significance of the concept of “Darwinian Fitness” to natural selection. A species is not capable of continuing evolution simply by surviving. The Darwinian Fitnessindicates the number of offspring’s a creature can have. The more offspring’s it is able toproduce, the more fit it is, and therefore will have more offsprings to carry out the favoredtrait that it carried to survive through natural selection. 22) Define species Species is a group of individuals who mate among themselves and produce healthyoffsprings 23) Explain what is meant by reproductive isolations Reproductive isolations are conditions and factors that do now enable successfulreproduction of different or even the same species. Factors from genetics to surroundingenvironment do not allow them to get close and mate, and therefore will isolate them interms of reproducing offspring’s. 24) Using examples, discuss the 5 prezygotic barriers to speciation. Prezygotic barriers are reproductive isolating mechanisms that prohibit reproduction evenbefore the zygote is formed. 1. Behavioral Isolation: When the way the species acts or behaves affects the way they’re attracted by females. For example, the way a bird or a frog mightsing or dance to attract mates. 2. Temporal Isolation: When times of mating seasons aren’t the same between species and won’t match the right time and therefore won’t reproduce. Forexample, some flowers have different mating seasons and times. 3. Ecological Isolation : Environments and geographical barriers that block them from mating. For example, some snakes like being in water while some don’t,so those 2 snakes won’t be mating 4. Mechanical Isolation : When genitals of a species aren’t compatible with another genital of the same species. Damsel flies male genitals aren’tcompatible. 5. Gametic isolation: when the chromosomes or sperm doesn’t survive in the body of the female and will die off before fertilization begins. 25) Discuss three postzygotic barriers to speciation.
Post-zygotic barriers are reproductive barriers that prevents a normal healthy hybrid. 1. Reduced Hybrid variability : many zygotes don’t even survive due to a lethal gene, or incorrect number of chromosomes within the gamete cells. The zygotewill terminate production probably after the first few mitosis cycles. 2. Reduced zygotic variability: most of the hybrids are sterile for their weird number of zygotes and rare amount of their hybrids with that number ofchromosomes 3. Hybrid Breakdown : The F1 generation may be able to make new F2 generation but the F2 generation won’t be able to reproduce anothergeneration, and the hybrid species will slowly die off. 26) Contrast allopatric and sympatric speciation identifying situations in which eachis most likely to occur. Allopatric speciation is where a physical barrier separates a population into smaller groups. Due to differences in local environments, they’ve adapted and changed allelefrequencies where they change so much to become a completely new species on theirprivate location. Due to such a vast genetic change, they are unable to mate with previousgenerations from the original larger mass of the population. Sympatric Speciation is where a group of the population is separated in terms of who they mate and how their genes are distributed throughout this single population. Differentpractices may trigger them to mate with only specific types, creating offspring’s to do thesame, creating a barrier for which who they can mate and limiting the spread of thosealleles. 27) Briefly compare gradualism and punctuated equilibrium as patterns of speciation. Gradualism states that the morphing of species takes place at a random rate and does not have a direct relationship with when it diverges to a new species. They conduct speciationslowly and gradually. Punctuated equilibrium states that species live without changing until they extinct, and go through large amounts of change to quickly form new species at any given time. 28) Apply the evolutionary principles learned in this unit to observations in nature. Sexual Selection: How boys look for hot girls to date in human sociology, prettier girls get guys faster than the ones who aren’t Natural selection : Those species who don’t blend in with the darkness of the leaves on dark leaved trees will be seen and eaten faster than those who are blended in Common Ancestry: dogs, humans, apes, and many many species have eyes, nose, mouth, and ears in a similar way as we do 29) Define artificial selection and describe examples Artificial selection is where humans play a role in selecting, adding, or removing a type ofanimal from an entire population, speeding up evolution and modifying the traditions thatnatural selection might follow. An example of which is with cod fishes on the east coast. For
years, fishermen have been picking the largest possible fishes they could find. They wereregulated to leave the smaller ones behind as they would “grow into large fishes andreproduce”. However, in an evolutionary standpoint, the smaller fishes are left to live,meaning that the allele frequencies of the larger fish are decreasing, while the alleles for thesmaller fishes are dominating. This means that if they kept reproducing, the possibility ofsmall fish would be greater and greater and the genes for larger fish would eventuallydisappear.