Natural Selection Lab

Natural Selection Lab Pre-Lab Questions 1. What variables can you influence in this lab? We can influence phenotypic, environmental, and selection factors. 2. Define what a genetic mutation is. How do genetic mutations happen? How often? A genetic mutation is a change in DNA sequencing. They happen randomly in every generation. 3. What do the terms fitness and adaptation mean? What is the difference between the two? ← Fitness is ability to reproduce. Adaptation is the ability to acclimate to a new environment. The difference between fitness and adaptation is that fitness is a measure of beneficial or deleterious adaptations. 4. What selection factors might affect an animal population besides the ones used in this lab? ← Some selection factors that might affect animal population is climate, water, and competition. Designing The Experiment In this Lab you will be controlling the mutations and environment of a population of rabbits. Your will create four hypotheses and design an experiment to test each one. Your hypothesis will follow the format where you fill in the (...) with your own ideas and reasons. I hypothesize that Brown fur rabbits will be more likely to survive under predation pressure within the equator environment, because they will be able to blend into the sand and prevent predators from noticing them. I hypothesize that long tail rabbits will be less likely to survive under predation pressure within the equator environment, because they will be easier to see on brown sand and easier for predators to grab. I hypothesize that long teeth rabbits will be more likely to survive under predation pressure within the arctic environment, because they will be more able to depend themselves. ***You must make at least one hypothesis for each of the three different types of phenotype mutations*** Fore a c he xpe r i me nty oumus tha v eac ont r ol( nomut a t i on)a n dfil li nt hef ol l o wi n gc ha r t Experiment and Hypothesis Pheno type Selective Factor CONTROL Group Initial Population at F3 CONTROL Group Final Population Experment Group Initial Population at F3 Experiment Group Final Population Conclusion/ Observation Br own Br ow Pr edat 18 Fur–wi l l nFur i on s ur vi v e pr ess u r e 0 7 Br ownbunni es Cont i nu s ur vi v ebest ous andt ak eov er Pr edat i o t hewor l d. n LongTai l Long Pr edat 18 –won’ t Tai l i on s ur vi v e pr ess u r e 0 7 0 Longt ai l bunni esdi dnot s ur vi v eduet o t hei robvi ous t ai lt hatc anbe s eenby pr edat or s . Long Teet h– wi l l s ur vi v e 0 13 Cont i nu ous popul at i on Longt eet h bunni ess ur vi v e bes tbec ause t heycan def end t hems el v es bet t erandt hey bl endi nt ot hei r envi r onment . Long Pr edat 18 Teet i on h pr ess u r e • For each of the experiments, begin by adding a friend and a mutation. Wait until the F3 generation before adding the selective factor. After adding the selective factor let the simulation run for another 3 or 4 generations. • Use the population numbers from the chart to get you numbers for the table, remember you can zoom in and out on the chart to get more accurate reads. • Repeat for experiments 2, 3 and 4 Post-Lab Questions 1. Based upon your evidence from the simulation what conclusion are you able to make about each of the three different types of phenotypes in rabbits? The color of fur that camouflages best in its environment survives and results in an exponential population growth. The length of the tail results in longer tailed rabbits being more easily to succumb to predators. therefore there is a faster reduction of these species due to their more visible tail. The long teeth of a rabbit allows them to survive best because they can defend themselves better and blend well into their environment. 2. What happens to animals that cannot compete as well with other animals in the wild? Animals that cannot compete as well as other animals tend to be naturally selected for and eventually become extinct because they are outcompeted by more fit animals. 3. Sometimes animals that are introduced into an area that they never lived in before, out-compete and endanger resident species, why do you think this happens? This happens because these new animals may be more compatible with the new environment and less likely to be preyed on by predators. 4. If only one species is considered the "fittest", why do we still have so many variations among species. Why do some birds have very long pointy beaks, while other birds have short flat beaks? Although one species may be considered the “fittest”, they are not necessarily the “fittest” in every environment. For example, in one environment, birds may be where they need to reach in the dirt for worms. It would be beneficial to have a longer beak in this situation. Whereas, in an environment where birds eat seeds, they don’t necessarily need a long beak to reach for them. 5. How do you think diseases can affect natural selection? Diseases can affect natural selection because it may weed out weaker species and have the remaining species be the ones who are immune. 6. How does this simulation mimic natural selection? In what ways does this simulation fail to represent the process of natural selection? This simulation mimics natural selection by showing how species evolve and what how genetic variants can either help or harm a specific species. It fails to represent the process of natural selection because it does not include all the environmental factors that would occur, such as co-habitants, diseases, etc.