Week 3 Learning

This week in biology we continued to learn about evolution mostly through lectures, and worksheets.

LECTURE: EVIDENCE FOR EVOLUTION

• Falsifiability
  • Scientific thoughts can never be proven
• Hypothesis
  • A testable statement about the universe
• Theories
  • A major unifying framework supported by all evidence currently known
• Laws
  • A deduced fact that will always hold true if given certain conditions

FOSSIL RECORDS

• Isotopes are used to figure out how old an organism is based on the half life of the isotope.
• Transitional Fossils
  • Show evolutionary links between groups of organisms
• Homologous Record
  • Similar characteristics resulting in common ancestry
• Analogous Record
  • Similarities in adaptations resulting from similar evolutionary pressures.
• Vestigial Organs
  • Structures that serve little to no function

LECTURE: MOLECULAR RECORD

• Genetic Code
  • Universal code used by ribosomes
• Building family trees
  • Closely related species are the same line of descent until their divergence from a common ancestor, this creates genetic differences
  • Fewer differences=more recently diverged
• Genome sequences
  • All our genomes are sequenced
  •  23 chromosomes
• Selection
  • Artificial
    • Selective breeding
    • Uses variations in the breed
• Biogeography
  • Original evidence that informed Darwin
  • Organisms close to each other are found in similar areas

PHYLOGENIC TREES

• Trace the path of evolution. Each “branch” of the tree is the development of a separate species.

QUESTIONS/COMMENTS

• At what point is selective breeding illegal?

LINKS

• https://www.hhmi.org/biointeractive/creating-phylogenetic-trees-dna-sequences