Evolution A change in allele frequency in a group over time Evolution Facts and Misconceptions Evolution is much a fact as the fact that planets go around the Sun TRUE Evolution is something a person should either believe in or not believe in FALSE Evolution is a process that includes the origin of life FALSE Evolution is primarily concerned with the origin of humans FALSE According to evolution people came from monkeys a long time ago FALSE Evolution was first proposed and explained by Charles Darwin FALSE Evolution is also known as Natural Selection FALSE Evolution is something that happens to individual organisms FALSE Evolution is a totally random process a series of accidents FALSE Evolution was developed as an idea to destroy or undermine religion FALSE Evolution has been tested and challenged many times but has always been supported by Big dinosaurs were common during the time of early humans FALSE Evolution involves individuals changing in order to adapt to their environment FALSE According to evolution new species usually results from major mutations in a single Most of the major groups of animals suddenly appeared in the Cambrian Explosion The formation of complex structures like the eye can now be easily explained by the results TRUE generation FALSE FALSE evolution TRUE Individuals do NOT evolve Populations do particular geographic area Population a group of individuals of the same species that live and interbreed in a Members of a population become adapted to the environment in which they live Creation vs Evolution A nasty old fight explained a reasonable new way Natural Selection Evolution by natural selection occurs when o Heritable variation leads to differential reproductive success Variation between individuals of the same species is due to Genetic differences between individuals heritable variation Different environmental factors experienced by different individuals non heritable variation o Ex Child with tall genes but family starved the child Both genes and environment can contribute to variation Genetic variation Environment variation What is the source of genetic variation Why did the mutations that led to heritable variation in ladybug color occur DNA Polymerase is not perfect o Mutations occur at RANDOM Biological Fitness Ability of an individual to produce surviving and fertile offspring o Compared to others in the same population o In a particular environment Fitness is relative Fitness is ability of an individual to produce surviving and fertile offspring o Compared to others in the same population in a particular environment Effects of Climate Change Natural Selection Compare to historical data o Some species of plant now flower earlier because growing season is longer o Canadian squirrels now breed earlier longer growing seasons o A species of American mosquito waits longer before entering winter dormancy all due to temperature is increasing Is this due to natural selection 1st Primary Literature Paper Rapid evolution of flowering time by an annual plant in response to a climate fluctuation Frank S J et al PNAS Chapter 24 Evolution by Natural Selection Vestigial Traits traits that are remnants of our evolutionary past Ex Monkey tail used for balance and locomotion vs human tailbone primate erect hair insulation emotional display vs human goose bumps Homology Similarities Genetic Developmental o Ex Human and fruit fly have 90 identical amino acids o Looking at developing embryos o Ex Comparing baby chicks humans house cats with gill pouches and tails Structural o Skeletal homology o Ex Textbook image basic arm bones Phylogenetic Tree Reading Bioskills 3 pg B 4 Monophyletic Group An ancestral species and ALL its descendants o One Cut Test one cut to set everything free Fitness Tradeoffs Natural selection forces compromises o If you have 5 to buy all of your food for the day do you pick the most filling or most nutritious or more energy dense o You pick something mid range in all 3 categories Evolution change in allele frequency in a population 4 Mechanisms o Natural Selection increased reproductive success o Genetic Drift random o Gene Flow population changes as individuals move taking alleles too o Mutation introduces brand new alleles Measuring and Quantifying Allele Frequency We can count alleles But what do you compare them to What is the control Enter Utopia the fictional land where allele frequencies are always constant and predictable
View Full Document
Unlocking...