Genesis and Genetics Matthew Price

Transcription

1 Genesis and Genetics Matthew Price Apologetics and Creation Camp 16 June 2018 Karakariki Christian Camp, Waikato, NZ 1

2 What is Science? 2

3 What is Science? Hypothesis Theory Start with a hypothesis; a reasonable idea Finish with a theory; a very robust understanding Has to overcome many hurdles! Repeatable Evidence-based Simple Falsifiable Hypothesis Universal Theory 3

4 What is Science? A good scientific theory: 1. Has explanatory power It explains existing data. 2. Has predictive power Makes predictions about unknown data 3. Is simple (Occam s Razor) Doesn t require extra ad hoc hypotheses ( auxiliary hypotheses ) Caution: story-telling! Falsification Successful prediction Theory not proven, but strengthened Unsuccessful prediction Theory disproven Auxiliary Hypothesis? 4

5 What is Science? No amount of experimentation can ever prove me right; a single experiment can prove me wrong. Albert Einstein 5

6 The Incredulity of Saint Thomas Michelangelo Merisi da Caravaggio ( ) God mercifully invites investigation 6

7 Christianity Testable? The bible is full of testable claims, e.g.: Historical Jewish exile (Egypt, Babylon) Life, death and resurrection of Jesus Archaelogical Ancient cities, etc. Forensic Crucifixion details (e.g. flow of blood/water) Geological The roundness of earth The water cycle ( Doesn t prove, but builds a very strong case) Events in Genesis provide many testable hypotheses, e.g.: Cosmology: Expectations of earth s specialness Geology: Expectations of a global Flood Genetics: Expectations of human populations 7

8 Genesis History Three key events recorded in Genesis will have testable predictions in population genetics: 1. Adam and Eve: The founding population 2. The Flood: A population bottleneck 3. Tower of Babel: Population migration 8

9 Keeping Score Evolution vs. Creation Pass: Prediction successful! Fail: Prediction unsuccessful! Auxiliary Hypothesis added

10 Genetics 101 If our DNA is a book, each chromosome is a chapter We have 46 different chromosomes: 22 pairs of autosomes 1 pair of sex chromosomes (XX or XY) or? For every pair: one from Mum; one from Dad Potentially two different copies of a gene (2 alleles) X Y 10

11 Genetics 101 When we pass on our DNA, recombination shuffles each chromosome: Which chromosome can never recombine? 11

12 Genetics 101 The chromosomes are nuclear DNA they reside in the cell s nucleus Mitochondria are the power plants of the cell, and have their own DNA (mtdna) Nucleus At fertilisation, all mitochondria are from the egg cell So mtdna is only maternal Mitochondria mtdna 12

13 Genetics 101 DNA segments which don t change each generation are ideal for understanding population history Lineage A Lineage B Lineage C With rare mutations, genetic families are created Which types of DNA would be suitable for this? 13

14 Genetics 101 Depending on variation and migration history, lineages can be found globally or just regionally One original population with existing variation Population migrates to different regions New variation is regional Existing variation is global unless a small sub-population loses variation by chance 14

15 1. Founding Population 15

16 1. Founding Population There is a lot of human genetic diversity where did it come from? A founding population which we re all descended from Evolution: ~10,000 founders; 1 million years ago Creation: 2 founders (Adam & Eve); 6,000 years ago 16

17 1. Founding Population Evolution: 1 million years Lots of time to accumulate mutations Mutation rate now known to be very high 10,000 founders Lots of genetic diversity, even for Y-chromosomes and mtdna Expect genes with 2 alleles (biallelic), 3, 4, 5 alleles etc. Most alleles geographically specific, due to historic migration 1. Very high genetic diversity overall 2. Diversity of Y-chr and mtdna 3. Multi-allelic genes 4. Alleles regional 17

18 1. Founding Population Creation: 2 founders, Adam & Eve 2-4 alleles per gene probably only 2 if Eve a clone One Y-chromosome (Adam) and one mtdna (Eve) Most major biallelic genes global (as all founders had them!) 6,000 years Some mutations; not much though Not many genes with 3+ alleles 1. Moderate genetic diversity 2. Low Y-chr and mtdna diversity 3. Very few multi-allelic genes 4. Alleles global 18

19 1. Founding Population Human population = 7.6 billion but, Effective population size N e = 10,000 i.e. 10,000 people could represent all human genetics! Moderate genetic diversity Very little Y-chromosome diversity Men are very related (for Y) Most genes only biallelic very few with 3+ alleles Major biallelic genes found globally 19

20 1. Founding Population Evolution vs. Creation Pass +1 Diversity (not mod.) +1 Mostly biallelic Pass +2 Mod. Diversity +1 Low Y diversity +2 Very biallelic +1 Biallelic global Fail +1 High Y diversity +1 Biallelic regional 20 0 Fail Hyp 02 0 Hyp 20

21 2. Population Bottleneck 21

22 2. Population Bottleneck A population bottleneck is when a devastating event reduces a population to a few individuals Only some survive reproduce Both Evolution and Creation worldviews have a major population bottleneck: Evolution: An auxiliary (extra) hypothesis to account for low genetic diversity Creation: The biblical Flood but diversity has been lost 22

23 2. Population Bottleneck Evolution: Not very specific expectations There will be a decrease in diversity: Some mtdna lineages Some Y-chromosome lineages Number of lineages not specified 1. Y-chr diversity low 2. X-chr diversity low 3. mtdna diversity low 23

24 2. Population Bottleneck Creation: Has very specific expectations These provide falsification tests! The world s population was reduced to 8 people: Noah, his wife, his 3 sons and their wives! Testing ahead This specifies the number of X and Y chromosomes and mtdna 24

25 2. Population Bottleneck Creation: How many Y-chromosomes? Noah had one Y-chromosome Each son inherited the same Y-chromosome Therefore only one Y-chromosome! Noah Shem Ham Japheth 1. Very low Y-chr diversity (1 lineage) 25

26 2. Population Bottleneck Mr & Mrs Noah Creation: How many X-chromosomes? Noah had one X-chromosome Didn t pass this on to his sons though! His wife had two X-chromosomes Each son inherited an X-chromosome from their mother Each of Noah s daughter-in-laws had two X-chromosomes Mr & Mrs Shem Mr & Mrs Ham Mr & Mrs Japheth 1. Very low Y-chr diversity (1 lineage) 2. Good X-chr diversity (~8 & recomb.) 26

27 2. Population Bottleneck Creation: How many mtdna lineages? Only maternally inherited Each son inherited the same mtdna, but they didn t pass it on Each daughter-in-law inherited their own mtdna from the general population??? Shem s wife Ham s wife Japheth s wife 1. Very low Y-chr diversity (1 lineage) 2. Good X-chr diversity (~8 & recomb.) 3. Low mtdna diversity (3 lineages) 27

28 2. Population Bottleneck High X-chromosome genetic diversity Due to multiple lineages and recombinations Only 1 main (global) Y-chromosome lineage Three main (global) mtdna lineages M, N and R 8 mutations 1 mutation M N R 28

29 2. Population Bottleneck Evolution vs. Creation Pass 3 +1 Low diversity Pass Low diversity +1 One Y-chr lineage +1 Three mtdna lin. Fail 0 0 Fail Hyp 2 0 Hyp 29

30 3. Population Migration 30

31 3. Population Migration Before Tower of Babel: One population, in one place, with one language Now the whole earth had one language and one speech. Gen 11:1 About 5 generations from the Flood Noah Shem Arpachshad Shelah Eber Peleg Two sons were born to Eber: One was named Peleg, because in his time the earth was divided Gen 10:25a Approximately 1,000 10,000 people at Babel From Noah to Peleg, did people freely mingle and marry? During those generations, some mutations create sub-lineages (for Y, mtdna, etc.) New variation (i.e. mutations) will be global P 31

32 3. Population Migration After Tower of Babel: Separate populations, separate languages, separate places Come, let Us go down and confuse their language, that they may not understand one another s speech. So the Lord scattered them abroad from there over the face of all the earth, and they ceased building the city. Gen 11:7 8 For the first time, human population geographically separated New variation (i.e. mutations) will be regional 32

33 3. Population Migration How did God separate people into groups? These were the families of the sons of Noah, according to their generations, in their nations; and from these the nations were divided on the earth after the flood. Gen 10:32 God separated people by paternal inheritance e.g. Sort by father Y-chromosome variation (low) now group-specific Therefore geographically specific mtdna variation (3 lineages) not group-specific Therefore global distribution 33

34 3. Population Migration Either Evolution: Worldwide Y-chromosome and mtdna distribution similar 1. Bottleneck with immediate migration (i.e. small groups): Both Y & mtdna variation characteristically regional 2. Bottleneck without immediate migration (i.e. large groups): Both Y & mtdna variation characteristically global However, Y-chromosome could be more global Men travel for war, trading, etc. 1. Y-chr & mtdna distr. similar 2. If anything, Y-chr more global 34

35 3. Population Migration Creation: Worldwide Y-chromosome and mtdna distribution different Y-chromosome diversity (low) regional mtdna diversity (i.e. 3 main lineages) global 1. Y-chr regional 2. mtdna global 35

36 3. Population Migration Very little Y-chromosome variation, and this variation is regional Three main mtdna lineages, found globally 36

37 3. Population Migration Evolution vs. Creation Pass Pass +1 Y-chr lineages regional +1 mtdna lineages global +1 Different Fail mtdna & Y-chr distributions +1 Y-chr more regional! 20 0 Fail Hyp 2 0 Hyp 37

38 Final Score: Evolution vs. Creation Pass 3 11 Pass Fail 2 0 Fail Hyp 2 0 Hyp 38

39 Key Points A good scientific theory: Must do more than just explain existing data As competing theories can be explained using the same data Must predict unknown data i.e. Must pass tests which are fail-able (falsifiable) Must be simple (Occam s razor) Fails can be addressed with extra hypotheses, but this burdens the theory! Theories can be disproven, but not proven The strength of a theory is in it passing many falsification tests, while remaining simple 39

40 Key Points Genesis has 3 key events which predict human genetics: Founding population (Adam & Eve) Population bottleneck (Noah s Flood) Population dispersal (Tower of Babel) Where Evolution falters, these Creation events successfully predict: Main alleles are biallelic and globally distributed Low/moderate genetic diversity Very low Y-chromosome diversity; small variations regional Three mitochondrial lineages, found globally Evolution struggles to account for the data; a Creation model predicts it very nicely 40