Evolution

1. Evolution BI30-LE2 Examine the significance of evolution as a key unifying theme in biology through the principles processes and patterns of biological evolution.

2. Evolution • What is it? • What do you know about it? • What do you want to know about it?

3. Evolution • What is it?Change in the genetic makeup of a population over time. • What do you know about it? • What do you want to know about it? Crash Course Big History: Evolutionary Epic

4. Evolution What we’re covering: • Common misconceptions (OpenStax Ch. 18-1 as a guiding tool or use your devices to pursue the following information). • Key Principles of Evolution • Human Evolution and Cladograms • Evidence for Evolution • Speciation • Isolation • Evolution over Generations

5. Common Misconceptions of Evolution (Ch 18.1 will help!) How might these be wrong? Answer independently, then, when prompted, with a partner. • Individuals evolve. • Natural selection is evolution. • Evolution is random. • Evolution is just a theory. • Evolution explains the origins of life. • Organisms evolve on purpose. Still not clear? Give this video a watch and then do the quiz at https://loganpetlak.ca/what-exactly-is-evolution/ Go to Socrative Student LoginSocrative Room Name: 98QHCGFW7

6. Common Misconceptions of Evolution (Ch 18.1 will help!) How might these be wrong? Answer independently, then, when prompted, with a partner. • Individuals evolve.The genetic makeup of populations “evolve”. • Natural selection is evolution.It is one of several mechanisms in which evolution occurs. • Evolution is random.While some events causing it may be random, who lives and who dies normally isn’t. • Evolution is just a theory.Scientific theories carry much more weight than how it is conventionally used. • Evolution explains the origins of life.Only explains how life has come to be and the diversity of life. • Organisms evolve on purpose.Not normally an active choice, just genetic lottery-winning.

7. Key Principles and Processes of Evolution • Descent with Modification • Fitness as a result of adaptation and struggle for existence. • Natural selection (need variation – genetic diversity) • Genetic drift • Selective breeding • Divergent/Convergent evolution.

8. Descent with modification • Our _____________ become _____________ or _____________. • Example: if being hairy kept you warm in a constantly cold environment, you’d be more likely to reproduce and pass on this _______________ to your _____________ in the population.

9. Descent with modification • Over time and generations the traits providing a reproductive advantage become more common within the population. • Our descendants become modified or changed. • Example: if being hairy kept you warm in a constantly cold environment, you’d be more likely to reproduce and pass on this modification to your descendants in the population.

10. “Fitness” • Result of adaptation and the struggle for existence. • Adaptation – • Fitness

11. “Fitness” • Result of adaptation and the struggle for existence. • Adaptation – a heritable trait that helps the survival of an organism in its present environment. • Fitness does not necessarily mean strength – it could be smarts, camouflage, or other traits that allow an organism to survive.

12. Natural selection • the process whereby organisms better adapted to their environment tend to survive and produce more offspring.  • Nature selects ______ or __________ a particular trait. • Hair analogy in a cold environment – hair would be selected for. No hair would be selected against.

13. Battle of the Beaks – LabWho Wants to Live for A Million Years - Activity Natural selection • the process whereby organisms better adapted to their environment tend to survive and produce more offspring.  • Nature selects “for” or “against” a particular trait. • Hair analogy in a cold environment – hair would be selected for. No hair would be selected against.

14. Genetic Drift • variation in the relative frequency of different genotypes in a small population, owing to the ___________________________ of particular genes as individuals die or do not reproduce. • Do we remember/know what a genotype is? This can lead to the disappearance of a particular genotype/allele.

15. Genetic Drift • variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individuals die or do not reproduce.Chance disappearance means that natural selection or other traits have no control over who lives, dies, and reproduces. • Random event! Like a meteor! • Do we remember/know what a genotype is? This can lead to the disappearance of a particular genotype/allele.

16. Genetic Drift and the Bottleneck Effect • Genetic drift basically means that there is the opportunity for the chance disappearance of a trait in a population without the organism being better adapted to the environment. • Bottleneck effect is a similar idea when the population is significantly thinned or decreased leading to a decline in genetic diversity. The population is forced through a bottleneck. Example: Hair colour and a random disappearance of people in the classroom.

17. Genetic Drift and the Bottleneck Effect • Genetic drift basically means that there is the opportunity for the chance disappearance of a trait in a population without the organism being better adapted to the environment. • Bottleneck effect is a similar idea when the population is significantly thinned or decreased leading to a decline in genetic diversity. The population is forced through a bottleneck.These bottleneck effects can lead to new speciation, however, if new ecological niches become available (decline in pop = increase in resource availability) Example: Hair colour and a random disappearance of people in the classroom.

18. Selective breeding • __________ ___________ (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics). They do this by choosing a specific animal or plant males and females to sexually reproduce and have offspring together. • This is how GMOs are everywhere.

19. Selective breeding • Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics). They do this by choosing a specific animal or plant males and females to sexually reproduce and have offspring together. • This is how GMOs are everywhere.

20. Determining Evolutionary Relationships • We use concepts of evolution to establish evolutionary relationships between species as well as analyze the prevalence of certain traits that may “appear” despite differences in ancestry.Divergent/convergent evolution reflects this. • This, in combination with other forms of evidence, help us paint a picture of the history of earth.

21. Divergent/Convergent Evolution • ______________ ___________ – when two species evolve in diverse directions from a common point. Can be observed in cladistics. • ______________ ___________– two similar traits may evolve despite a non-similar ancestry.

22. Divergent/Convergent Evolution • Divergent evolution – when two species evolve in diverse directions from a common point. Can be observed in cladistics. Cats and humans both have similar bone structures. • Convergent evolution – two similar traits may evolve despite a non-similar ancestry. Dragonflies and birds. Both have a means of flight, different anatomical structure.

23. Evolution Importance • Ultimately, all of these different aspects of evolution help us establish potentials links and ancestry between species. • But what’s the point of that? Why bother? What benefits could be gained? • Why should people understand its misconceptions? Fundamental approaches to life. • From studying organisms evolution, we try to classify them into similar groups based on certain characteristics – these groups (getting more specific) are called Kingdom, Phylum, Class, Order, Family, Genus, Species. • With species names like Homo sapiens written in binomial nomenclature.

24. Evolution Importance • Ultimately, all of these different aspects of evolution help us establish potentials links and ancestry between species. • But what’s the point of that? Why bother? What benefits could be gained?Medical implications (using similar organisms to make inferences about impacts on humans).Scientific curiousity/understanding origins and future progression of life. • Why should people understand its misconceptions? Fundamental approaches to life. To understanding Biology and connectedness of nature. • From studying organisms evolution, we try to classify them into similar groups based on certain characteristics – these groups (getting more specific) are called (Domain) Kingdom, Phylum, Class, Order, Family, Genus, Species. • With species names like Homo sapiens written in binomial nomenclature.

25. Divergent – Classifying - Cladistics A particular system of _____________ (genetics and traits) classification is called cladistics Cladistics uses ____________________ to establish evolutionary relationships in a _____________ (shown right).The traits that separate organisms on the tree would signify _____________ _____________. A shared derived characteris a feature that apparently evolved only within the group under consideration.

26. Divergent – Classifying - Cladistics A particular system of phylogenetic (genetics and traits) classification is called cladistics Cladistics uses shared derived characters to establish evolutionary relationships in a cladogram (shown right).The traits that separate organisms on the tree would signify divergent evolution. A shared derived characteris a feature that apparently evolved only within the group under consideration.

27. Creation of a Cladogram

28. Make your own! • Create a Cladogram Assignment • Complete the front page – making a tree from the chart given. • Create your own chart and tree on the back page. Select six organisms and five traits that will separate them from one another. • Which organisms are most closely related, which are least closely related?

29. Why are cladograms important? • When looking at creatures through the scope of divergent/convergent evolution… we can begin to see organismal ancestry and how organisms relate to one another and when certain shared derived characteristics came into existence. • Different types of evidence that scientists gather helps us create cladograms and can separate some domains/species from one another and paint a picture as to the origins of life and a Last Universal Common Ancestor (LUCA).

31. Dog Breed Tree • Is a Jack Russel Terrier more closely related to a Great Pyrenees or a Poodle and why? • How does this connect into selective breeding? • Is this morally okay? Are there instances in which it is not morally okay?

32. Human Evolution • https://en.wikipedia.org/wiki/Human_evolution • Family ______________ = adaptation that sets it apart is bipedalism • Homo _______ (skillful human) – 2.8 million years ago. A mutation occurred in which the SRGAP2 gene doubled – a gene responsible for the wiring of our frontal cortex (large part of learning)… so they started becoming bigger (more processing power = smarter = evolutionary advantage) • Homo _______ (upright man)– using fire and tools 1.3 million years ago. • Homo _______ (wise human) eventually evolved form a branch of this and began replacing branches of this around the world _______-________~ years ago. Over that time gradual changes in behaviour occurred coinciding with subtle changes to societies and some changes to our species as a whole.

33. Human Evolution • https://en.wikipedia.org/wiki/Human_evolution • Family: Hominidae/hominini = adaptation that sets it apart is bipedalism • Homo habilis(skillful human) – 2.8 million years ago. A mutation occurred in which the SRGAP2 gene doubled – a gene responsible for the wiring of our frontal cortex (large part of learning)… so they started becoming bigger (more processing power = smarter = evolutionary advantage) • Homo erectus (upright human) – using fire and tools - 1.3 million years ago. • Homo sapiens (wise human) eventually evolved form a branch of this and began replacing branches of this around the world 250,000-400,000~ years ago. • Over that time gradual changes in behaviour occurred coinciding with subtle changes to societies and some changes to our species as a whole.

36. Human Evolution Theory • _____ ___ _________ Hypothesis – small group of Homo sapiens evolved out of Africa. _______________ ____– mitochondrial DNA is passed from mother to offspring without recombination (apart from mutations stays the same).

37. Human Evolution Theory • Out of Africa Hypothesis – small group of Homo sapiens evolved out of Africa. “Mitochondrial Eve” – mitochondrial DNA is passed from mother to offspring without recombination (apart from mutations stays the same). *New evidence is showing that there may be some male mitochondrial DNA influencing offspring. Crash Course Big History: Human Evolution

38. Human Socio-cultural Evolution “Girls only want guys who have good skills” • What traits or characteristics in Canadian culture are evolutionarily advantageous/disadvantageous? • Given current trends – what beliefs, characteristics or traits do you think humans as a whole will evolve to? • When considering human evolution, we have to consider how events in history may have adjusted the collective genetic makeup of our species as a whole, and how worldviews and ideologies may continue to influence it today.

39. Crash Courses on Human Evolution Human Evolution: Crash Course Big History Why Human Evolution Matters: Crash Course Big History Points that stood out Points that stood out:

40. Crash Courses on Human Evolution Human Evolution: Crash Course Big History Why Human Evolution Matters: Crash Course Big History Points that stood out Points that stood out: • “Did the development of agriculture ‘ruin’ our species?”Work week hours (may have been less in the past). • Cumulative or collective knowledge is a big part of how humans “evolved” so rapidly. • Supervolcano at Mt. Toba bottleneck effect(ed) the human population causing us to branch out from them.

41. Evidence for Evolution Organisms share core processes and features widely distributed throughout species today.

42. Evidence for evolution Evolution itself is informed and supported by manydifferent branches of biology/science as a whole.

43. Evidence for evolution Evolution itself is informed and supported by manydifferent branches of biology/science as a whole. • Fossils - Geological • Anatomy and embryology – homologous analogous structures. • Biogeography • Molecular biology • Chemistry

44. Evidence for evolution • What is geographic evidence for evolution? • What is geological evidence for evolution? • What is physical (anatomical) evidence for evolution? • What is chemical evidence for evolution? • Genetic evidence for evolution?

45. Fossils • Fossil record often provides clues to evolutionary relationships. • The fossil record may provide the framework of a phylogenetic tree, but a systematic taxonomist would seek to confirm the information it provided with other lines of evidence. • As we find fossils –

46. Fossils • Fossil record often provides clues to evolutionary relationships. • The fossil record may provide the framework of a phylogenetic tree, but a systematic taxonomist would seek to confirm the information it provided with other lines of evidence. • As we find fossils – we can infer when that organism existed and compare its structure to that of other fossils or existing organisms.

47. Geological Evidence • Age of rocks/sediment where a fossil is found • Different depths infer different “age”

48. Anatomy (Morphology) and Embryology • Some organisms upon comparison have homologous and analogous structures. • What do these terms mean? Homologous – Analogous - • Some organism follow similar embryological processes.

49. Anatomy - Homologous • Homologous features, features that have similar structure and come from similar embryonic layers but have completely different functions

50. Anatomy - Analogous • Analogous features are ones that come from different embryological development but look similar and perform similar functions, like the wings of bats and the wings of insects. • Which one (analogous or homologous) connects to divergent evolution, which one to convergent?