Quiz 4

• Evolution


  The relative change in the genetic traits of a population or accessive generations
• Population


  The smallest unit that can evolve
• Evolution


  Any shift in a gene pool
• Microevolution

  Gradual change in allele frequencies in a population over time
• Microevolution


  • Pesticide resistance, antibiotic resistance in bacteria, COVID variants
• Macroevolution

  Large scale change including new species or groups of organisms
• How characteristics change

  1. Crossing over during meiosis (prophase I)

  2. Mutations

  3. Random assortment of chromosomes (Metaphase I)

  4. Sexual reproduction
• These processes create change in chromosomes or which chromosomes are inherited and has change in a species
• Not all these changes are beneficial to a species' survival at the point in its evolutionary history, but some may
• Adaptation


  A particular structure, physiology (internal) or behavior, developing from gradual change in genetic traits of a population, that helps organisms survive and reproduce in a particular environment
• Adaptations


  • Camouflage, hibernation, circadian rhythms, excellent sense of smell, vision
• Variation


  A significant deviation from the normal biological form, function or structure
• Variations


  • Albino mouse, partially striped zebra
• Natural Selection


  The process whereby the characteristics of a population changes because individuals with certain heritable traits survive local environments and pass their traits to their offspring
• Natural Selection


  • The environmental conditions determine which individuals in a population are most fit to survive
  • Genes from the surviving individuals are passed on to the offspring
  • Can lead to the extirpation or extinction of a species
• Fitness


  A measure of how well an organism fits with the environment. An organism that is "fit" is well suited to the current environment and most likely will survive.
• Artificial Selection


  The deliberate selection of particular traits by human activity, determining which individuals in a population have the desired traits to be passed on to the next generation
• Artificial Selection


  • Breeding dogs, horses, crops to produce desired traits
• Not all breeding (artificial selection) brings about positive results
• Selecting 'wasted' traits as 'unwanted' leads to decreased variety in a species after generations of breeding
• Selective breeding can lead to inbreeding, which weakens a species and makes it more susceptible to disease and genetic disorders
• The peppered moth


  • Occurs in two forms: flecked (white wings with flecks of black) and black
• Natural selection is the process whereby the characteristics of a population changes as individuals with certain heritable traits survive in their local environments and pass their traits to their offspring
• The peppered moth case demonstrated natural selection at work
• Historical contributors to evolutionary thought

  • Greek philosophers like Aristotle and Plato
  • George-Louis Leclerc, Comte de Buffon
  • Mary Anning
  • Georges Cuvier
  • Charles Lyell
  • Thomas Malthus
  • Jean-Baptiste Lamarck
• Catastrophism


  The idea that catastrophes account for the appearance and disappearance of species within the fossil record
• Uniformitarianism


  The idea that geological processes operate at the same rate today as they always did
• Inheritance of acquired characteristics

  The idea that modifications acquired during a lifetime can be passed on to offspring
• Lamarck's theory of inheritance of acquired characteristics was incorrect
• Natural selection


  The process whereby the characteristics of a population changes because individuals with certain heritable traits survive local environments and pass their traits to their offspring
• Peppered moth case


  • Demonstrated natural selection at work
• Our ideas on evolution have been shaped by many people throughout the course of history
• Historical Contributors to Evolutionary Thought

  • Greek Philosophers
  • George Louis Leclerc, Comte de Buffon
  • Merrenung
  • George Cuvier
• Greek Philosophers (Aristotle and Plato)


  Did not believe in evolution, said all organisms which could exist were already created
• Even up to the sixteenth century the predominant paradigm in western culture was that all species of organisms came into existence at the same time and remained unchanged
• George Louis Leclerc, Comte de Buffon

  Published Histoire Naturelle in 1749, noted similarities between humans and apes and speculated a common ancestor, noted the world must be much older than 6000 years
• Mary Anning: Collected and studied fossils, donated and sold many fossils to scientists such as Cuvier, regarded as a pioneer of paleontology
• George Cuvier

  Said to be the founder of Paleontology (Study of Fossils), opposed evolution, studied the fossil record and noted that something was causing species to appear and disappear, developed the idea of Catastrophism - the idea that catastrophes account for the disappearance and appearance of species within the fossil record (e.g. Noah's flood caused disappearance of organisms from the fossil record)
• Wallace worked independently of Darwin


  Created the same theory as Darwin's theory of Natural Selection
• Wallace and Darwin


  They would both worked together evanally