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Whakapapa & Mathematical Thinking

Genealogy, Networks & Exponential Growth Through Cultural Connection

Exploring how whakapapa (genealogy) reveals fundamental mathematical concepts including exponential growth, network theory, and the mathematics of human connection.

Mathematics Lives in Our Connections

Whakapapa is far more than a list of names - it's a sophisticated mathematical network that reveals exponential growth, probability theory, and the stunning complexity of human relationships. Every person's whakapapa contains the same mathematical patterns that govern population dynamics, genetics, and network theory.

"Ko wai au? He uri nō wai au?"

Who am I? Whose descendant am I? - Questions that lead to exponential mathematics

The Mathematics of Ancestry - Exponential Growth

The Exponential Pattern

Each person has exactly 2 biological parents, 4 grandparents, 8 great-grandparents... This creates a perfect exponential sequence: 2¹, 2², 2³, 2⁴, 2⁵...

Whakapapa Tree - Mathematical Structure

You (Generation 0)
2⁰ = 1 person
Parent 1 Parent 2
2¹ = 2 people
GP1 GP2 GP3 GP4
2² = 4 people
GGP1 GGP2 GGP3 GGP4 GGP5 GGP6 GGP7 GGP8
2³ = 8 people

Whakapapa Exponential Formula

Ancestors = 2ⁿ (where n = generations back)

Example: 10 generations back = 2¹⁰ = 1,024 ancestors!

Whakatōpū - Mathematical Investigations

Investigation 1: Your Personal Exponential Growth

Calculate Your Ancestry

Using the formula 2ⁿ, calculate how many ancestors you have at each generation:

Generations Back (n) Power Calculation Number of Ancestors
3 (Great-grandparents) 2 × 2 × 2 8
5 2⁵ ____ ____
8 2⁸ ____ ____
10 2¹⁰ Use calculator! ____
15 2¹⁵ Use calculator! ____

Critical Thinking Questions

  1. At what generation does the number of ancestors exceed the current population of New Zealand (5.1 million)?
  2. If we go back 1000 years (approximately 40 generations), how many ancestors should you theoretically have?
  3. Why is this number impossible? What does this tell us about shared ancestry?

Investigation 2: Whānau Network Mathematics

Scenario: A whānau reunion brings together descendants of a couple who lived 200 years ago.

Family Growth Pattern

Assumptions for modeling:

  • Original couple: 2 people
  • Each generation has an average of 3 children per couple
  • 25 years between generations
  • 200 years = 8 generations

Mathematical Challenges

  1. Generation 1: 2 people have 3 children = __ people in Gen 2
  2. If pattern continues, how many people in Generation 4?
  3. What formula could model this growth?
  4. How many people might attend the reunion?

Advanced Challenge: Network Connections

If 50 people attend the reunion, and everyone greets everyone else once, how many handshakes occur? (Hint: This is a combinations problem: C(50,2) = 50!/(2!(50-2)!))

Investigation 3: Whakatōhea & Mathematical Decision Making

Cultural Context: In traditional Māori society, important decisions were made collectively by whānau, hapū, and iwi. Understanding the mathematics of representation helps ensure fair participation.

Hui Representation Problem

A hui needs to make a decision that affects three hapū:

  • Hapū A: 150 members
  • Hapū B: 300 members
  • Hapū C: 450 members

Challenge: If the hui has 30 representative positions, how should they be distributed fairly?

Mathematical Solutions:
  1. Equal representation: Each hapū gets 10 representatives. Is this fair? Why/why not?
  2. Proportional representation: Calculate what proportion each hapū should receive based on population.
  3. Formula: (Hapū population ÷ Total population) × 30 positions = Representatives for that hapū
Hapū Population Calculation Representatives
Hapū A 150 (150 ÷ 900) × 30 = ____
Hapū B 300 ____ ____
Hapū C 450 ____ ____

Whakangā Ake - Advanced Mathematical Extensions

Logarithmic Relationships

If you have 1,024 ancestors 10 generations back, how many generations would give you approximately 1 million ancestors? Use: n = log₂(ancestors)

Probability in Genealogy

What's the probability that two random New Zealanders share a common ancestor within 20 generations? Research the mathematical concept of "degrees of separation."

Graph Theory

Family trees are mathematical graphs. Research how graph theory mathematics is used in genetics, social networks, and DNA analysis.

Population Genetics

Investigate the Hardy-Weinberg principle: how do gene frequencies change over generations? What mathematical models predict genetic diversity?

Ā Muri, Ā Mua - Mathematical Applications Today

Where Whakapapa Mathematics is Used

DNA Analysis & Genealogy

  • 23andMe and AncestryDNA use exponential mathematics to calculate relationship probabilities
  • Genetic algorithms use the same mathematical principles as family trees
  • Population genetics models predict disease inheritance patterns

Social Networks & Technology

  • Facebook's "People You May Know" uses network mathematics
  • LinkedIn connection recommendations use graph theory
  • Contact tracing for disease outbreaks uses the same mathematical models

Māori Cultural Applications

  • Iwi Registration: Mathematical verification of whakapapa connections for iwi membership
  • Settlement Distribution: Using population mathematics to determine fair distribution of treaty settlements
  • Cultural Preservation: Network analysis to understand how cultural knowledge spreads through whānau networks
  • Language Revitalization: Mathematical modeling to predict optimal strategies for Te Reo Māori transmission

Whakaaro - Mathematical Thinking Reflection

Essential Understanding Check

  1. Explain exponential growth: Why does the number of ancestors grow so rapidly as you go back in time?
  2. Mathematical impossibility: Why can't you actually have 2²⁰ ancestors 20 generations back?
  3. Cultural connections: How does understanding the mathematics of whakapapa change your perspective on human connection?
  4. Real-world applications: Give two examples of how exponential growth mathematics appears in current technology or science.

Extended Challenge

Research the mathematical concept of "most recent common ancestor" (MRCA). Using mathematical models, approximately when did all humans share a common ancestor? How does this mathematical finding connect to the concept of whakatōhea (collective responsibility)?