BIOLOGY FOR LIFE
  • Syllabus
    • Core >
      • 1: Cell Biology >
        • 1.1: Introduction to Cells
        • 1.2: Ultrastructure of Cells
        • 1.3: Membrane Structure
        • 1.4: Membrane Transport
        • 1.5: The Origin of Cells
        • 1.6: Cell Division
      • 2: Molecular Biology >
        • 2.1: Molecules to Metabolism
        • 2.2: Water
        • 2.3: Carbohydrates and Lipids
        • 2.4: Proteins
        • 2.5: Enzymes
        • 2.6: DNA and RNA
        • 2.7: DNA Replication, Transcription and Translation
        • 2.8: Cell Respiration
        • 2.9: Photosynthesis
      • 3: Genetics >
        • 3.1: Genes
        • 3.2: Chromosomes
        • 3.3: Meiosis
        • 3.4: Inheritance
        • 3.5: Genetic Modification and Biotechnology
      • 4: Ecology >
        • 4.1: Species, Communities and Ecosystems
        • 4.2: Energy Flow
        • 4.3: Carbon Cycling
        • 4.4: Climate Change
      • 5: Evolution and Biodiversity >
        • 5.1: Evidence for Evolution
        • 5.2: Natural Selection
        • 5.3: Classification and Biodiversity
        • 5.4: Cladistics
      • 6: Human Physiology >
        • 6.1: Digestion and Absorption
        • 6.2: The Blood System
        • 6.3: Defense Against Infectious Disease
        • 6.4: Gas Exchange
        • 6.5: Neurons and Synapses
        • 6.6: Hormones, Homeostasis and Reproduction
    • Higher Level >
      • 7: Nucleic Acids >
        • 7.1: DNA Structure and Replication
        • 7.2: Transcription and Gene Expression
        • 7.3: Translation
      • 8: Metabolism, Cell Respiration & Photosynthesis >
        • 8.1: Metabolism
        • 8.2: Cell Respiration
        • 8.3: Photosynthesis
      • 9: Plant Biology >
        • 9.1: Transport in the Xylem of Plants
        • 9.2: Transport in the Phloem of Plants
        • 9.3: Growth in Plants
        • 9.4: Reproduction in Plants
      • 10: Genetics and Evolution >
        • 10.1: Meiosis
        • 10.2: Inheritance
        • 10.3: Gene Pools and Speciation
      • 11: Animal Physiology >
        • 11.1: Antibody Production and Vaccination
        • 11.2: Movement
        • 11.3: Kidney and Osmoregulation
        • 11.4: Sexual Reproduction
    • Options >
      • D: Human Physiology >
        • D.1: Human Nutrition
        • D.2: Digestion
        • D.3: Functions of the Liver
        • D.4: The Heart
        • D.5: Hormones and Metabolism
        • D.6: Transport of Respiratory Gases
  • IB Requirements
    • Learner Profile
    • Group 4 Project
    • External Exam
    • Internal Assessment >
      • Personal Engagement
      • Exploration
      • Analysis
      • Evaluation
      • Communication
    • Extended Essay
  • Investigation Skills
    • Lab Safety
    • Microscopy
    • Lab Drawings
    • Data Tables
    • Measurement
    • Statistics >
      • Descriptive Statistics >
        • Skew
        • Measures of Central Tendancy
        • Measures of Spread
        • Pearson Correlation
      • Inferential Statistics >
        • T-Test
        • ANOVA
        • Kruskal-Wallis
        • X2 Test for Independence
        • X2 Goodness of Fit
    • Graphing >
      • Graphing with Excel
      • Interpreting Error Bars
    • Error Analysis
  • Course Info
    • Above & Beyond >
      • Biology Club
      • Pumpkin Carving
      • Scavenger Hunt
      • Science News
      • IB Bio Dance
      • Wood Duck Project
      • Invasive Crayfish Project
    • Assessment >
      • Class Grading IB Bio I
      • Class Grading IB Bio II
      • Daily Quizzes
      • WICC Assessment
      • Lab Practicals
    • Assessment Statements
    • Class Photos
    • Recommendations
    • Supplemental Reading
  • Contact
  • About
    • Philosophy
    • Resume
    • Reflection
    • Site Feedback
    • Favorite Quotes
    • AEF Blog
  • Expeditions
    • Bahamas (2009)
    • Trinidad (2010)
    • Trinidad (2011)
    • Ecuador (2012)
    • Trinidad (2013)
    • Peru (2014)
    • Bahamas (2015)
    • Peru (2016)
    • Costa Rica (2017)
    • Costa Rica (2018)
    • Arizona (2022)
  • Summer Ecology Research

Topic 5.4:
​Cladistics

Essential Idea:  The ancestry of groups of species can be deduced by comparing their base or amino acid sequences.
  • Outline answer to each objective statement for topic 5.4 (coming soon)
  • Quizlet study set for this topic
At SHS, Topic 5.4 is taught in the following class unit(s):​​​​​​
  • Adaptations to Niches through Time (unit 20b)​
  • Cladistics (unit 23)
5.4.U1  A clade is a group of organisms that have evolved from a common ancestor.
  • Define clade and cladistics.
5.4.U2  Evidence for which species are part of a clade can be obtained from the base sequences of a gene or the corresponding amino acid sequence of a protein.
  • Outline the relationship between time, evolutionary relationships and biological sequences (nitrogenous base or amino acid).
5.4.U3  Sequence differences accumulate gradually so there is a positive correlation between the number of differences between two species and the time since they diverged from a common ancestor.​
  • Outline the use of a “molecular clock” to determine time since divergence between two species.
  • State the source of differences between biological sequences (nitrogenous base or amino acid).
5.4.U4  Traits can be analogous or homologous.​
  • Contrast analogous and homologous traits.
  • State an example of analogous and homologous traits.
5.4.U5  Cladograms are tree diagrams that show the most probable sequence of divergence in clades.​
  • Define cladogram and node.
  • Outline how computer programs analyze biological sequence data to create cladograms.
  • Identify members of clades given a cladogram.
5.4.U6  Evidence from cladistics has shown that classifications of some groups based on structure did not correspond with the evolutionary origins of a group or species.​
  • Outline the role of technological advancements in the development of cladistics.
  • Explain why the development of cladistics lead to the reclassification of some species.
5.4.A1  Cladograms including human and other primates.
  • Interpret a cladogram depicting primate species. ​
5.4.A2  Reclassification of the figwort family using evidence from cladistics.
  • Outline the reason and evidence for the reclassification of the figwort family.
5.4.S1  Analysis of cladograms to deduce evolutionary relationships.​
  • Analyze a cladogram to explain the evolutionary relationship between species.
  • Discuss the use of cladograms as hypotheses of evolutionary relationships.
5.4.NOS  Falsification of theories with one theory being superseded by another- plant families have been reclassified as a result of evidence from cladistics.
  • Outline the reason why biological theories may change with time.

In the News:

  • Move over, DNA: ancient proteins are starting to reveal humanity’s history (2019-06-26)
  • DNA Analysis Reveals a Genus of Plants Hiding in Plain Sight (2018-09-04)
  • Rise of the grasshoppers: New analysis redraws evolutionary tree for major insect family (2018-07-24)
  • The Very First Animal Appeared Amid an Explosion of DNA (2018-05-04)
  • Genomics and the Origin of Citrus (2018-02-07)
  • Mapping the first family tree for tropical forests (2018-02-05)
  • Surprise in the kangaroo family tree (2017-12-04)
  • Ancient Fossil Offers a New European Ancestor to Giraffes (2017-11-01)
  • New Orangutan Species Could be the Most Endangered Great Ape (2017-11-03)
  • Convergent evolution of mimetic butterflies confounds classification (2017-09-20)
  • ​African Genes Tracked Back (2013-08-27)
  • Earliest Unfrozen Ancient DNA Reveals Some Bear Facts (2013-09-09)
  • Proteins help solve taxonomy riddle (2013-11-05)
  • Americas’ natives have European roots (2013-11-20)
  • Ancient European genomes reveal jumbled ancestry (2014-01-02)
  • Ancient cholera mysteriously disappeared (2014-01-09)
  • Why sharks have no bones (2014-01-08)
  • Debate over which mammals roamed with the dinosaurs (2014-01-15)
  • The Chicken Didn't Cross The Pacific To South America (2014-03-18)
  • Chicken project gets off the ground (2014-05-27)
  • The origin of bright-colored birds (2014-06-26)
  • Tiny new species of frog from Brazil with a heroic name (2014-07-24)
  • Spider gene study reveals tangled evolution (2014-07-21)
  • ​Philippine tarsier: Genetic proof of a new variety (2014-08-19)
  • Evolutionary history of honeybees revealed by genomics (2014-08-24)
  • Common European MRSA originated in Africa, study concludes (2014-08-26)
  • Puzzle of Darwin’s 'strangest animals' finally solved (2015-03-18)
  • Puzzle of Darwin’s 'strangest animals' finally solved (2015-03-18)
  • Earth's First Snake Likely Evolved On Land, Not In Water (2015-05-19)
  • Ancient wolf genome pushes back dawn of the dog (2016-05-21)
  • Who Let The Dogs In? We Did, About 30,000 Years Ago (2016-05-22)
  • Malaria family tree has bird roots (2016-03-24)
  • ​Historic fossils find new life telling the story of ancient proteins (2016-06-15)
  • DNA Study Reveals the One and Only Wolf Species in North America (2016-07-27)
  • DNA reveals that giraffes are four species — not one (2016-09-08)
  • Ale genomics: how humans tamed beer yeast (2016-09-08)
  • Thanks to fossil DNA, this ‘island murderer’ is finally getting its day in court (2016-09-13)
  • Oldest-ever proteins extracted from 3.8-million-year-old ostrich shells (2016-09-16)
  • How the Brown Rat Conquered New York City (and Every Other One, Too) (2016-10-27)
  • Genetic study shakes up the elephant family tree (2017-06-06)
  • Africats to the Purr-ymids: DNA study reveals long tale of cat domestication (2017-06-19)
  • Strange Mammals That Stumped Darwin Finally Find a Home (2017-07-03)
  • Genome sequencing shows spiders, scorpions share ancestor (2017-08-01)
  • How amphibians crossed continents: DNA helps piece together 300-million-year journey (2014-08-04)
  • Researchers Clear 'Patient Zero' From AIDS Origin Story (2016-10-26)
  • Tracing the evolution of bird reproduction​ (2016-08-10)
  • ​Elephant history rewritten by ancient genomes​ (2016-09-16)
  • How pygmy moths started to diversify 100 million years ago (2016-10-31)
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"When we try to pick out anything by itself, we find it hitched to everything else in the Universe." 
 John Muir,   1911
  • Syllabus
    • Core >
      • 1: Cell Biology >
        • 1.1: Introduction to Cells
        • 1.2: Ultrastructure of Cells
        • 1.3: Membrane Structure
        • 1.4: Membrane Transport
        • 1.5: The Origin of Cells
        • 1.6: Cell Division
      • 2: Molecular Biology >
        • 2.1: Molecules to Metabolism
        • 2.2: Water
        • 2.3: Carbohydrates and Lipids
        • 2.4: Proteins
        • 2.5: Enzymes
        • 2.6: DNA and RNA
        • 2.7: DNA Replication, Transcription and Translation
        • 2.8: Cell Respiration
        • 2.9: Photosynthesis
      • 3: Genetics >
        • 3.1: Genes
        • 3.2: Chromosomes
        • 3.3: Meiosis
        • 3.4: Inheritance
        • 3.5: Genetic Modification and Biotechnology
      • 4: Ecology >
        • 4.1: Species, Communities and Ecosystems
        • 4.2: Energy Flow
        • 4.3: Carbon Cycling
        • 4.4: Climate Change
      • 5: Evolution and Biodiversity >
        • 5.1: Evidence for Evolution
        • 5.2: Natural Selection
        • 5.3: Classification and Biodiversity
        • 5.4: Cladistics
      • 6: Human Physiology >
        • 6.1: Digestion and Absorption
        • 6.2: The Blood System
        • 6.3: Defense Against Infectious Disease
        • 6.4: Gas Exchange
        • 6.5: Neurons and Synapses
        • 6.6: Hormones, Homeostasis and Reproduction
    • Higher Level >
      • 7: Nucleic Acids >
        • 7.1: DNA Structure and Replication
        • 7.2: Transcription and Gene Expression
        • 7.3: Translation
      • 8: Metabolism, Cell Respiration & Photosynthesis >
        • 8.1: Metabolism
        • 8.2: Cell Respiration
        • 8.3: Photosynthesis
      • 9: Plant Biology >
        • 9.1: Transport in the Xylem of Plants
        • 9.2: Transport in the Phloem of Plants
        • 9.3: Growth in Plants
        • 9.4: Reproduction in Plants
      • 10: Genetics and Evolution >
        • 10.1: Meiosis
        • 10.2: Inheritance
        • 10.3: Gene Pools and Speciation
      • 11: Animal Physiology >
        • 11.1: Antibody Production and Vaccination
        • 11.2: Movement
        • 11.3: Kidney and Osmoregulation
        • 11.4: Sexual Reproduction
    • Options >
      • D: Human Physiology >
        • D.1: Human Nutrition
        • D.2: Digestion
        • D.3: Functions of the Liver
        • D.4: The Heart
        • D.5: Hormones and Metabolism
        • D.6: Transport of Respiratory Gases
  • IB Requirements
    • Learner Profile
    • Group 4 Project
    • External Exam
    • Internal Assessment >
      • Personal Engagement
      • Exploration
      • Analysis
      • Evaluation
      • Communication
    • Extended Essay
  • Investigation Skills
    • Lab Safety
    • Microscopy
    • Lab Drawings
    • Data Tables
    • Measurement
    • Statistics >
      • Descriptive Statistics >
        • Skew
        • Measures of Central Tendancy
        • Measures of Spread
        • Pearson Correlation
      • Inferential Statistics >
        • T-Test
        • ANOVA
        • Kruskal-Wallis
        • X2 Test for Independence
        • X2 Goodness of Fit
    • Graphing >
      • Graphing with Excel
      • Interpreting Error Bars
    • Error Analysis
  • Course Info
    • Above & Beyond >
      • Biology Club
      • Pumpkin Carving
      • Scavenger Hunt
      • Science News
      • IB Bio Dance
      • Wood Duck Project
      • Invasive Crayfish Project
    • Assessment >
      • Class Grading IB Bio I
      • Class Grading IB Bio II
      • Daily Quizzes
      • WICC Assessment
      • Lab Practicals
    • Assessment Statements
    • Class Photos
    • Recommendations
    • Supplemental Reading
  • Contact
  • About
    • Philosophy
    • Resume
    • Reflection
    • Site Feedback
    • Favorite Quotes
    • AEF Blog
  • Expeditions
    • Bahamas (2009)
    • Trinidad (2010)
    • Trinidad (2011)
    • Ecuador (2012)
    • Trinidad (2013)
    • Peru (2014)
    • Bahamas (2015)
    • Peru (2016)
    • Costa Rica (2017)
    • Costa Rica (2018)
    • Arizona (2022)
  • Summer Ecology Research