BIOLOGICAL CONCEPTS BIOL 101
Virginia Commonwealth University
Popular in Course
Popular in Biology
This 5 page Class Notes was uploaded by Alysha Quigley on Wednesday October 28, 2015. The Class Notes belongs to BIOL 101 at Virginia Commonwealth University taught by Adam Chupp in Fall. Since its upload, it has received 14 views. For similar materials see /class/230647/biol-101-virginia-commonwealth-university in Biology at Virginia Commonwealth University.
Reviews for BIOLOGICAL CONCEPTS
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/28/15
Evolution 1192009 30600 PM Alfred Wallace o Developed and communicated ideas from thousands of miles away o Darwin and Wallace were both naturalists Observing the morphological dietary reproductive and social characteristics of organisms o A generation younger than Darwin Nichewhat you do on a daily basis your habits Voyages c From 18311836 Darwin served as naturalist aboard the HMS Beagle o Wallace voyaged through Malaysia and Indonesia from 1854 to 1862 Influences o Darwin and Wallace were both influenced by Thomas Malthus 1798 Essay on the principles of Population Observations o Island Biogeaography 0 Observed patterns in species characteristics and distribution 0 Island species are more similar in composition to the nearest mainland than they are to distant islands 0 Island populations were founded by small numbers of mainland species which then evolved into distinct species in distinctly different habitats Sumatran Tiger 0 Adaptive Radiation the evolution of species into a diversity of previously unoccupied habitats or niches 0 Species from distinct geographic area are similar because they share a recent common ancestor but differ according to local environmental conditions Species characteristics depend upon ancestry and the environment Conclusion o Preservation of favorable variations is called natural selection 0 Darwin previously believed that all things had existed in perpetuity in accordance with the common romanticized Victorian thought On the Origin of Species challenged the concept of humanity and religious authority The theory of evolution by natural selection was accepted by the scientific community after a century of cross examination o Evidence for Evolution 0 Biogeographical evidence 0 Fossil Evidence Radioisotope dating 0 Anatomical evidence 0 Molecular evidence o Fossil Record 0 Mineralized bones that provide an incomplete record of past fauna Changes in phenotype are documented 0 Transitional species demonstrate common ancestry Radioisotopic decay facilitates accurate dating o Anatomical Record 0 Homologous structures 9 divergent evolution 0 Analogous structures 9 convergent evolution 0 Vestigial structures express ancestral traits o Molecular evidence 0 Amino acid substitutions in a given protein reflect the distance of time since divergence Change through Natural Selection o Genertic variation among individuals o Life is a struggle limiting resources etc o Some phenotypes are favored o Successful phenotypes reproduce o Populations exhibit the successful traits Evolution o Descent with modification 0 Lamarck inheritance of acquired traits individual level Evolving Populations o Variation is introduced by 0 Mutation 0 Gene Flow immigration amp emigration O O O O 0 Genetic Drift due to chance Lose Traits Rare traits might become common a Bottleneck Effect n Founder Effect Non Random Mating Inbreeding Sexual selection HardyWeinberg Equilibrium Selection for Traits Forms of Selection n Directional o Extreme phenotype favored o Prickly pear cactus are preyed upon by Peccaries o Cacti with fewer spines are eaten more frequently 0 Cacti with more spines prosper n Stabilizing o An intermediate phenotype is selected 0 Prickly pear cacti are preyed upon by Peccary Cacti with more spines survive o Wasp deposits larvae at the base of cactus spines Cacti with fewer spines survive 0 Neither extreme is favored in the middle n Disruptive o Extreme phenotypes are selected 0 Extreme phenotypes are better adapted 0 Selection removes intermediate phenotype o Extremes begin to diverge 0 Intermediate phenotype is dissolved o Create a speciation event o Macroevolutionary change Speciation Results from n Reproductive isolation o Prezygotic o Temporalreproductive timing 0 Behavioral courtship patterns 0 Mechanical gamete compatibility o Postzygotic o Zygote mortalitymitosis fails 0 Hybrid sterilityinfertile offspring 0 F2 fitnesshybrids produce infertile offspring Species capable of producing viable offspring Sympatric Speciation n Within the same habitat a Gene flow disrupted because of niche specialization o Disruptive selection Allopatric speciation n Geographic isolation a Local adaptation n Reproductive isolation 1192009 30600 PM
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'