prezi/4jhwrsb5n6r6/are-we-all-african/

1. Humans came from Africa. What does this tell us about the diversity of Africans compared to Non-Africans? http://prezi.com/4jhwrsb5n6r6/are-we-all-african/

2. Please go back to the last page Go to the website. There are no facts here. … If you are still reading this, you are really stubborn. … I’m done.

3. Hardy Weinberg!!! How to solve it and practice problems! It’s easier then you think Halle. By: Savannah Olenick

4. What is Hardy-Weinburg? • If no evolution is occurring, then equilibrium will occur among the alleles, contingent upon a consistent generation of no evolution. • The formula allows us to detect change in allele frequencies among generations • In order for it to remain in effect, the following must occur (can never happen in real life): • No mutations (prevents new alleles from entering the population) • No gene flow (i.e., migration in or out of the population) • Random mating • Large population (prevents genetic drift (random chance)) • No selection for or against alleles.

5. The equations: What they mean • p²+2pq+q²=1 • p+q=1 • Percentage of homozygous dominant individuals • Percentage of heterozygous individuals • Percentage of homozygous recessive individuals • Frequency of dominant allele in population • Frequency of recessive allele in population • *use the first formula for problems in which you’re asked to find the percentage of a genotype in a population. (see problem portion in yellow) • *use the second formula for problems asking for the frequency of an allele in a population. (see problem portion in pink.)

6. Practice Problem: You have sampled a population in which you know that the percentage of the homozygous recessive genotype (aa) is 36 %. Using that 36%, calculate the following: The frequency of the “aa” genotype. The frequency of the “a” allele. The frequency of the “A” allele. The frequencies of the genotypes “AA” and “Aa.” The frequencies of the two possible phenotypes if “A” is completely dominant over “a.” The problem references “A,” which is referencing “A” as the dominant allele, P. The problem also references “a,” which is referencing “a” as the recessive allele, Q.

7. Given: The problem tells us that the percentage of homozygous recessive individuals is 36%. This represents “aa,” or, “q².” • Step 1. We know q² as 36%. So the next necessary step involves the equation p+q=1. In order to get q, simply take the square root of .36. • √.36= .6, so q=.6. • Substitute q into the equation above to find p. • P+.6=1 (1-.6=.4, so p=.4.) • The “p” is your dominant allele frequency. (A). The “q” is your recessive allele frequency. (a). • Substitute p & q into the other equation in order to find your homo- and heterozygous genotypes for AA, Aa, and aa. • p²+2pq+q²=1 • AA, or, p²= .16. • aa, or q²= .36. (given.) • Aa, or 2pq,=.48. (Determined by substituting p and q into the equation “2pq.” • (.16)+2(.4)(.6)+(.36)=1

8. Natural Selection vs. types of nonadaptative evolution (include genetic drift and gene flow)

9. Natural Selection vs. types of nonadaptative evolution Natural Selection – The gradual process by which biological traits become more or less common in a population as a function of the effect of inherited traits on the differential reproductive success of organisms interacting with their environment.

10. Types of non adaptive evolution Non-adaptive evolution: any change in allele frequency that does not by itself lead a population to become more adapted to its environment. Causes- mutation, genetic drift , gene flow Genetic drift- random changes in the allele frequency of a population between generations ; genetic drift tends to have more dramatic effects in smaller populations. Gene flow- the movement of alleles from one population to another, which may increase the genetic diversity of a population.

11. Types of Speciation (allo, sympatric)

12. Types of Speciation By:MarKeese Boyd

13. Allopathic Speciation Allopathic Speciation: geographic species (Ex. A river or mountain range)

14. Sympatric Speciation Member of species live side by side but are in different in species (Ex. some insects feed and reproduce on a single type of fruit. If some members of this species try another type of fruit, their offspring may be raised to visit that fruit)

15. PeripatricSpeciation when a small group becomes isolated from the main body of the species (Ex. Bottle neck effect)

16. How do I tell if 2 populations of similar organisms are 1 species? What data could I collect

17. Distinguishing Species Emily Ward

18. What is a species? A species is a population or group of populations whose members have the potential to interbreed in nature and produce viable ,fertile offspring.

19. What is a speciation? Speciation- An evolutionary process in which one species splits into two or more species

20. Types of Speciation Allopatric Speciation- The formation of new species in populations that are geographically isolated from one another Sympatric Speciation-The formation of new species in populations that live in the same geographic area

21. How can you tell if they are a species? They are a species if they can successfully make kids If the species cannot make a zygote, then they are not a species. Prezygotic barriers impede mating between species Post zygotic barriers will make sure that the egg gets fertilized but the offspring dies or is infertile

22. What types of evidence for phylogenic trees can be used and rate the evidence for accuracy?

23. Phylogeny By: Nick Ski

24. What? Phylogeny is • The history of the evolution of a species or group. • There is a proposition accepted in the scientific community that all organisms descended from a common ancestor.

25. How Is This Determined? • Since the vast majority of organisms that have ever lived are currently extinct, we have to rely on fossils. The main downfall of this is that fossils are usually so degraded, most pieces have to be filled in.

26. But… Most Accurate • We can easily make a short termed phylogenic tree of currently living organisms through genetic sequencing.

27. Why are mass extinctions important in radiation of species and evolution?

28. Why are mass extinctions important in radiation of species and evolution? Natasha Foertsch

29. Extinction itself promotes biotic interchange • Extinction leaves behind a host of empty niches so if a new species has good enough traits, it can use this niche as a resource. • When these species take on different niches and become isolated, they split which regenerates some of the diversity that was wiped out by the mass extinction. • These events lead to Adaptive radiation: The evolution of many new species from a single species, with each new species being adapted to new habitat or resource.

30. Some evolution happens when members of a population are severed from each other by geographic isolation • Allopatric Speciation: (1)geographic isolation followed by (2) reproductive isolation • The organisms that survive the extinction have many geographical, physiological and ecological opportunities for expansion (adaptive radiation), increasing the dominant species of the new period.

31. Examples: The most famous mass extinction that took place 65 million years ago when an asteroid ~10 kilometers in diameter struck the Yucatan peninsula is the Cretaceous – Paleogene (KPg) extinction. The elimination of so many species shifted the evolutionary landscape for the remaining species, and the result was a burst of speciation. Extinction event is a burst in mammalian speciation, as small mammals that survived the event fill niches left empty by the dinosaurs. Without this event, the trajectory of mammalian evolution would certainly look very different.

32. Things You Should Study: Adaptive radiation geographicisolation So pretty much after extinction, we start over but not completely from scratch. This is what causes diversity among new species.

33. Terms: Homologous, Analogous, Coevolution, convergent Evoltion

35. Characteristics of phylum: Annelida, Mollusca, Arthropoda, Echinodermata, Chordata. Also what’s a deuterostome?

36. Characteristics of phylum: Annelida, Mollusca, Arthropoda, Echinodermata, Chordata. Also what’s a deuterostome? Bradley MacGregor Period 2AB 1/30/14

37. Annelida Ex: are a large phylum of segmented worms, with over 2,000 modern species including ragworms, earthwormsand leeches Characteristics: segmented,They are bilaterally symmetrical, triploblastic, coelomate organisms. They have parapodia for locomotion

38. Phyla: Mollusca Ex: snail, clams, slugs, cuttlefish Characteristics: : Bilateral symmetry, three main body segments made of CaCO3 secreted by the mantle organ

39. Phyla: Arthropoda(jointed feet) Ex: Trilobites, scorpions, arachnids Characteristics: bilateral symmetry, exoskeleton mad of chitin, and a wide diversity of feeding

40. Phyla: Echinodermata (spiny skin) Ex: sea stars, sea cucumber, brittle stars, sand dollars, sea lilies Characteristics: The adults are recognizable by their (us usally five-point) radial symmetry Echinoderms are found at every ocean depth, from the intertidal zoneto the abyssal zone. The phylum contains about 7000 living species, making it the second-largest grouping of deuterostomes

41. Phyla: Chordata Ex: alligators, humans, fish, ect. Characteristics: has a back bone

42. deuterostomes A species that forms the anus first and has an exoskeleton mad of Ostia plates and a vascular system for locomotion

43. Make an accurate phylogentic tree from this data and explain how and why you made your decisions:

44. When creating a phylongenic tree, you want to look for the most closely related organisms. Making sure those who are most similar are shown closer in the tree, with the least similar farther apart. Data is usually shown like this…

45. Try it! • Ex.- Try to make one of your own using the chart in the previous slide! • Observe the chart, do you think the organisms with more similarities are more closely related than to those with less similarites? Why or why not? • When creating your tree, how did you decide where to place each group? What helped you to make that decision?