Stu lab 1 - lab assignment PDF

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ANTH 105: Human Evolution Lab 1: Genetics Part 1: Pigeonetics An understanding of Mendelian genetics is crucial for understanding the mechanisms and results of evolution. To demonstrate this, you are going to be playing a game: Pigeonetics! In this simulation, you are a pigeon breeder aiming to produce birds with specific traits. You will be able to predict the probability of these traits appearing through your understanding of genetic inheritance. The game is playable in your browser or as a mobile app, which is free. You may play either way. As you’re playing the game, you will work through this lab to answer questions about the role that genes play in determining physical appearance. Please go to: http://learn.genetics.utah.edu/content/pigeons/ or search for “University of Utah Pigeon Breeding” and click on “Pigeonetics.” Be sure the volume on your computer is not muted. There is narration and a very nice jazzy little soundtrack. The narration is important. As you work through the puzzles, answer the questions about the genetics of each trait and make any additional notes that you think will be helpful in solving the puzzles! The game automatically saves the puzzles that you have completed. Click the “pause” symbol in the lower right corner to see a list of the puzzles you have completed and to jump ahead to the puzzles you have remaining. During the introduction video, a TA will go over the first five puzzles as an example. Trait Sex (Puzzle 1)

Description Male or female

Crest (Puzzle 3)

A peak of feathers on the head

Questions Male sex chromosomes: Z, Z Female sex chromosomes: Z, W Is the allele for having a crest dominant or recessive? How do you know? Recessive and that’s because there are two alleles, crest and no crest.

As you work through the puzzles, you will need to answer the questions and write a brief description of the trait, as we’ve done for you in the first two. Please type directly in the boxes, or in a separate document if you could only download the PDF. Do not print the document and fill out the questions physically. Trait Slipper (Puzzle 1)

Wing pattern (Puzzle 3)

Description Feathers on the feet

List the 4 different possible patterns (alleles) for wing

Questions 1. How many different phenotypes are there for slipper feet? Three 2. What are the alleles for each of these phenotypes? Use S as; the letter to represent the alleles. SS, Ss, ss. 3. If a pigeon has one allele for the bar pattern and another

Feather Color (Puzzle 13)

Spread (Puzzle 17)

Dilute (Puzzle 23)

patterns for pigeons in order from most dominant to least dominant. You may wish to click the “explain” button for more information. 1. T-check allele 2. Check allele 3.Bar allele 4.Barless allele List the possible color alleles for pigeons in order from most dominant to least dominant. 1. Ash - red allele 2.Blue allele 3. Brown alle

for check, what phenotype will it have? check 4. If a pigeon has one allele for barless and another for tcheck, what phenotype will it have? T-Check

5. Notice that the inheritance of feather color was different in male and female birds. Please propose an explanation for why this might be. This happens because of the sexual dimorphism in the birds. 6. Is the allele for spread dominant or recessive? Dominant 7. How might the alleles for spread interact with the alleles for wing pattern? Through epistasis, where the spread allele underline wing patterns. 8. How do the dilute and recessive red alleles interact? (Hint: Look carefully at your offspring pigeon.) Through sex link via the z chromosome which has the dilute and not dilute allele.

9. Describe the phenotype of a pigeon with the following genotype: • Has two Z chromosomes: This will result in a male with either ash red, blue or brown phenotype. • Has one allele for crest and one allele for no crest: This is an inherited gene from parents to offspring’s (crest) through the sperm to the eggs. no crest. • Has one allele for slipper another for no slipper: This is inherited independently (no slipper) • Has two alleles for no grouse: No grouse • Has one allele for bar and another allele for check: Wing pattern will be check • Has one allele for brown and one allele for blue: Blue 10. What was the phenotype and genotype of your final pigeon in Puzzle 26?

Two ash red traits, 2 dilute traits, double z chromosome and 2 barless traits are for genotype while the phenotypes are no slipper, wing, and ash red.

11. What does it mean to say that a gene is epistatic? Which pigeon trait(s), if any, was or were epistatic? Traits depend on another trait to occur. The red recessive trait is epistatic to the wing pattern.

12. Is blue feather color dominant or recessive? Explain why that is a difficult question to answer. 13. Which, if any, pigeon traits were polygenic? What does that mean? Are there any human traits you can think of that are likely to be polygenic? Polygenic traits are the variations between species such as color and body shape. In human, there are different skin tones, heights and weights and in pigeons, there are colors and wings patterns.

Part 2: Beyond Mendelian Genetics While some traits are Mendelian traits— i.e., these traits are controlled by one gene—most traits are polygenetic or controlled by multiple genes. For example, height, eye color and skin color are all complex traits that are controlled by multiple genes—not just one. In fact, in the past few decades researchers have begun to uncover just how complex our traits are. Previously, our genetic code was thought to be the “blue-print” of who we are and what we could become. Instead, we are learning that factors such as the environment are much more important than we had previously suspected. Today, we know that many traits have multifactorial inheritance, or that many factors impact a trait—both genetic and environmental. For example, height is one of many multifactorial traits. Currently, over 700 gene variants have been associated with height, but other factors including an individual’s access to nutrients during growth and development as well as their mother’s access to nutrients while pregnant impact a person’s height. In Part 2 of this lab we will learn more about more complex traits and the growing field of epigenetics. Part 2a: Polygenetic and Multifactorial traits

Review the ThoughtCo. article from the prelab reading here https://www.thoughtco.com/polygenicinheritance-373444 and answer the following questions. 14. Choose one polygenetic trait discussed in the article and list it here Color . How many genes are believed to determine this trait

Eye 16

?

15. Mendelian traits are inherited through complete dominance, but polygenetic traits are more complex. In your own words, describe how polygenetic traits are determined. Polygenetic have inherited genes with multiple genes and can show up differently on the part of the body, such as having different eye color, body shape, and height. These traits are non – epistatic. Part 2b: Epigenetics

First, watch a short (5 minute) video on epigenetics here https://m.youtube.com/watch?v=_aAhcNjmvhc . Visit https://learn.genetics.utah.edu/content/epigenetics/inheritance/ and read a brief description on epigenetics, then answer the following questions. 16. In your own words, what is epigenetics and why is it important for understanding how traits are inherited? Epigenetics an inheritable gene that does not changes our DNA but rather lets the environment play a major role in what we inherit from our parents based on their life experiences and environments. It is important to know how these genes are inherited to determine which traits are inherited for human survival.

17. How many generations are exposed, and potentially impacted, by the same environmental conditions? Multiple generations. In your own words, explain how so many generations are potentially impacted by the same environmental conditions at once. A lot of generations are impacted exposed to the same environmental conditions because of the food that is being consumed and nature and nurture situations that exist today, which can also be passed on to future generations when today's generation starts to reproduce.

18. In your opinion, why is only understanding Mendelian inheritance patterns inadequate for understanding human variation of traits and conditions?...