Lesson 5: Evidence of Evolution

• Evolution is the slow, gradual change in a species over time.
• Evidence from fossils came from sedimentary rocks
• • A fossil is any remains or trace of an ancient organism. 
• How do fossils form?

  
  

  • Only the dead animal’s hard parts, such as bones, shells, and teeth, remain.
  • Under rare conditions, these parts become fossils.
• Mineralization


  The replacement of organic material by inorganic minerals.
• In fossils, what parts of animals remains?

  bones, shells, and teeth
• Mineralization is a common mode of fossilization
• Carbonization are when organisms are rapidly buried.
• Artificial Selection is when species variation occurred through mutation and sexual reproduction, but humans select features that are beneficial.
• Evidence from fossils - Solid evidence that the past organisms don’t look like the present organisms. 
• Example of Evidence from fossils?

  Burgess Shale from Yoho National Park in canada
• The process where small spaces between tissues hardens.

  Mineralization
• Artificial selection products of Mustard plant

  • Broccoli
  • Cauliflower
  • Cabbage
• Organisms from prior geographic region that were closely related but different species traveled into surrounding habitats and evolved in these far apart geographic regions.

  Geographic distribution
• 2 types of geographic distribution

  Convergent and Divergent
• Convergent distribution example is whale and shark having similar appearances.
• Convergent Distribution closely related yet different species live in different geographic locations evolved similarly and adapt to same environment.
• Evidence from Structure

  Structures in different organisms can be compared to infer common lineage.
• Evidences of Evolution

  • Fossils
  • Structure
  • Embryology
  • Molecular Homologies
• Homologous Structure


  Structures with the same set of bones that presumably evolved from common ancestor.
• Analogous Structure


  Structures that perform the same function but have very different embryological development or set of structures like bones.
• Example of Homologous Structure


  Deltoid Muscle
• Dinosaur fossils are the mineralized remains of bones and teeth.
• Vestigial Structures

  Structures or attributes that have lost most of its ancestral function in more recent species.
• Plica Semilunaris


  Third eyelid located at the corner of the eye
• Embryology


  Study of the development of an organism from an embryo to its adult form.
• Human embryo has a tail at the 4th week which disappears during the 8th week.
• Pharyngeal pouches become gills in fish, and parts of throat/ears in humans.
• According to Evidence from Molecular Homologies

  At the most basic level, all living organisms share:

  • The same genetic material (DNA)
  • The same, or highly similar, genetic codes
  • The same basic process of gene expression (transcription and translation)
  • The same molecular building blocks, such as amino acids
• Similarities of DNA and protein sequences to animals

  Monkey

  95%

  Mouse

  87%

  Chicken

  69%

  Frog

  54%

  Lamprey

  14%
• Techniques to Identify Molecular Homologies

  1. Gel Electrophoresis
  2. Protein Analysis / Amino Acid Sequencing
• Function of tailbone


  support for seated position
• Other term for tailbone - coccyx
• Gel Electrophoresis


  Technique used to separate DNA fragments according to their size.
• Other term for protein analysis

  Amino Acid Sequencing
• Protein Analysis/Amino acid sequencing


  The numbers represent the number of differences between protein samples.