Human Origins and Genetics

Summary

This heading gathers six groups of articles on where humans came from:  the hominin fossils, the record of ancestry in human DNA, the comparison with chimpanzees, race and skin color, the archaeology of symbols, and the biology of language.  Each tests the young-earth reading, in which all people descend from Adam and Eve about 6,000 years ago and from Noah's family a few centuries later, against what has been measured.  This page gives the overall verdict and a map.  It does not re-argue the children.

The evidence agrees with Genesis about what humans are, and disagrees with it about when, and about how humans relate to the apes.  The fossils sort into apes that walked upright and people, as young-earth writers said they would, with a band of small-brained mosaic fossils between that those writers place on both sides of their own line.  All living people form one shallow family, Neanderthals and Denisovans were people who had children with our ancestors, symbols and burial appear as early as the bones of modern humans do, and no ape has shown grammar.  On time the young-earth reading is badly strained:  fossil dates run from about 7 to about 900 times the years since the Flood,¹ measured rates of lasting change put mitochondrial Eve at 126,000 years or more, and recombination counts about 1,800 to 2,000 generations since Neanderthal genes entered Europeans, against 160 in 4,000 years.  These clocks run on different things, radioactive decay, mutation and the reshuffling of chromosomes in each generation, so no single speed-up of decay shortens them all, and no young-earth writer has yet specified or measured a mechanism that does.  The human and chimpanzee genomes are alike in the patterned way common descent predicts:  shared retrovirus positions, a fused chromosome, nested inversions and the fingerprints of known mutation processes.  The young-earth answer, that the differences were mostly built in, is coherent but fits that pattern only by stipulation.  Young-earth critics were right about several overstatements on the other side:  the 98.8 percent slogan, the claimed genetic disproof of a first couple, the late "human revolution" in behaviour, and the claims that apes were learning language.

The six groups:

1. Hominin Fossils. The young-earth division into apes and humans holds at both ends of the record and splits on the mosaic fossils between. It has no answer yet to the dates or to the rise of brain size with time.
2. Human Genetic Ancestry. Human DNA fits one origin for all people, and three of four standard arguments against a single first couple fail. It does not fit a recent one: mitochondrial Eve, Y-chromosome Adam and Africa's genetic depth all lie far beyond a post-Babel date.
3. Humans and Chimpanzees. The genomes are about 96 percent alike where they line up and 85 percent on a whole-genome count, and their differences fall in the pattern common descent predicts. The brain, gait, culture and life history differ greatly.
4. Race, Skin Color, and Common Ancestry. Humans are one shallow species, separate origins for the races failed, and skin color is many-gened. The shallow pattern fits both a recent African origin and a young-earth family; the clocks separate them.
5. Behavioral Modernity. Engraving, beads, pigment and burial appear with the earliest Homo sapiens and with Neanderthals, as young-earth writers expected. Their dates would need radioactive decay after Babel to run 12 to 250 times faster than today.
6. Human Uniqueness: Language, Mind, and FOXP2. No ape has shown grammar, FOXP2 is a speech-motor gene and not a language gene, and no gene or brain feature found so far explains syntax. The gap is real and fits the image of God, but it does not show how it arose.

Part 1: Hominin fossils

Young-earth writers read the hominin fossils as two separately created groups.  Peter Line put it this way in 2005:  "all the supposed apemen belong either to the genus Homo, and are descendants of Adam and Eve, or they belong to extinct apes."²  The division holds at both ends.  Lucy and the other australopiths were small-brained animals that walked upright, and Homo erectus, the Middle Pleistocene people, the Neanderthals, the Denisovans and the earliest Homo sapiens were people.  It splits on Homo habilis, Homo rudolfensis, Australopithecus sediba, Homo naledi and the small people of Flores and Luzon, where Todd Wood's answer, a human kind more varied than creationists had said, gives up the "unbridgeable morphological gap" Line promised.²³  The dates, and the rise of brain size with date, have no young-earth answer yet.  Read Hominin Fossils.

Part 2: Human genetic ancestry

Human DNA agrees with Genesis on the shape of human ancestry:  one maternal line, one paternal line, shallow and nested diversity, and a spread through the Near East for the non-African world.  Three of the four standard arguments against a single first couple do not test it, and BioLogos cut its own figure from 18 million years to half a million.  The disagreement is depth.  On Norfolk Island a deep family tree found 2 lasting mitochondrial changes where the young-earth rate predicts 54.6,⁴ the Y-chromosome pedigree rate alone puts the root of the Y tree at about 163,000 years,⁵ and the median time back to four ancestral copies of a stretch of the genome, which is all one couple can carry, is 495,000 years.  Neanderthal DNA survives in every population studied, and its depletion on the X chromosome, a sign of partial hybrid sterility, has no creationist answer.  Read Human Genetic Ancestry, which also explains why three versions of the Mitochondrial Eve article stand side by side.

Part 3: Humans and chimpanzees

The two genomes are about 96 percent alike where they line up and about 85 percent alike on a whole-genome count, and no percentage settles ancestry by itself.  The patterns do.  Retroviruses sit at the same places far more often than insertion preference allows, human chromosome 2 is a fusion in the condition of an old one, the inversions mostly nest as the ape family tree predicts, and the single-letter differences sit where new mutations arise today.  Young-earth critics were right about the 98.8 percent slogan, the human-guided early chimpanzee assemblies, the function of much "junk" DNA and the clock's calibration problems.  Their best position, that the differences were mostly created, requires more than 99.9 percent of them to be, and it fits the fingerprints of mutation only by stipulation.  What the percentages leave out is most of what makes a human:  a brain three times larger, a cheaper upright gait, language, cumulative culture and a slower life.  Read Humans and Chimpanzees.

Part 4: Race, skin color, and common ancestry

Most human genetic variation lies inside every population:  85.4 percent in Richard Lewontin's 1972 survey and 93 to 95 percent in Noah Rosenberg's 2002 survey of 1,056 people.  Ancestry is still written in the genome, and with thousands of markers a clustering program recovers continents without being told them, but the groups are gradations and nothing in the data ranks them.  The nineteenth-century theory that the races were created separately failed, and the monogenists, mostly Christians reading Genesis, were right.  Skin color is controlled by many genes, so the two-gene Punnett square in some creationist books should go.  A recent African origin and a young-earth family both predict a shallow, shared genome;  they part on the ages of alleles and the dates of ancient genomes, where the mainstream reading fits better today.  Read Race, Skin Color, and Common Ancestry.

Part 5: Behavioral modernity

Pigment at Pinnacle Point is dated to about 164,000 years, shell beads in Morocco to more than 142,000, and the engraved ochre at Blombos Cave to about 100,000 to 73,000, with Neanderthals using pigmented shells by 115,000 years ago.  Richard Klein's late "human revolution" 50,000 years ago has been given up by most of the field, and Marcus Ross, Peter Brummel and Todd Wood, who list art and burial among the marks of "advanced, human cognition and therefore the image of God",⁶ were closer to the record than Klein was.  The cost is time.  Placing the record from Blombos to Lascaux after Babel and inside a 700-year Ice Age needs radioactive decay to run roughly 80 to 250 times faster than today, after the period in which the accelerated-decay proposal places its speed-up.  The same three writers concede that "none of the dating methods have a widely accepted method of recalibrating to a creationist timescale."⁶  Read Behavioral Modernity.

Part 6: Human uniqueness

Apes taught symbols learned from about 50 to 161 of them, and Nim Chimpsky's signed utterances stayed 1.1 to 1.6 signs long while his vocabulary rose from 42 to 125 signs.  Kanzi the bonobo, the strongest case, understood new spoken requests about as well as a two-year-old girl tested the same way.  None has produced, or shown that it understands, the nested structure of human grammar.  FOXP2 is a gene needed for normal speech, its two human changes were shared by Neanderthals, and the 2002 claim that the human form swept through our species recently failed on larger data.  The gap fits the biblical claim that humans alone bear God's image, but Noam Chomsky, an evolutionist, predicts a sudden gap as firmly as a creationist does, so the gap alone does not decide between them.  Read Human Uniqueness:  Language, Mind, and FOXP2.

Part 7: Which article to read

1. Were Lucy and the australopiths human? Lucy and the Pre-Human Hominins.
2. Were Homo erectus, the Neanderthals and the Denisovans human, and how old are they? The Genus Homo, Neanderthals and Denisovans.
3. Why do creationists disagree about which fossils are human? Ape or Human? How Creationists Sort the Fossils.
4. Does brain size rise through the fossil record? Brain Size and the Order of the Fossils.
5. Could all people descend from one couple? Adam, Eve, and Human Genetic Diversity.
6. How old is mitochondrial Eve? Mitochondrial Eve and the Young-Earth Timeline, with its two rewrites listed under Human Genetic Ancestry.
7. Does the Y chromosome point to Noah? Y-Chromosome Adam and Noah.
8. Did people spread from Africa or from Babel? Out of Africa or Out of Babel?
9. Did our ancestors have children with Neanderthals and Denisovans? Archaic Admixture.
10. How similar are human and chimpanzee DNA? How Similar Are Human and Chimp DNA?
11. Is human chromosome 2 a fusion? Chromosome 2 Fusion.
12. Do shared retroviruses and broken genes show common descent? Shared Retroviruses and Pseudogenes.
13. Is gene order the same in humans and chimpanzees, and why do their Y chromosomes differ? Synteny, Gene Order, and the Y Chromosome.
14. When did humans and chimpanzees split, on measured mutation rates? The Human-Chimp Split and the Mutation Rate.
15. How does skin color work, and could one couple carry all of it? The Genetics of Skin Color.
16. Who taught that the races had separate origins, and who opposed it? Scientific Racism and Monogenesis.
17. When did people start making art and burying their dead? Behavioral Modernity.
18. Can apes learn language, and is FOXP2 a language gene? Human Uniqueness: Language, Mind, and FOXP2.
19. Did all languages come from one? Did Language Begin Once?
20. Is the mind more than the brain? Mind, Reason, and Consciousness.
21. Do Genesis 10 and 11 fit the archaeology of Mesopotamia and the history of languages? Babel, Language, and Human Dispersal, under History.
22. Do Egypt, the Neolithic and the peopling of Australia and the Americas run through the Flood date without a break? Human History Across the Flood Date, under History.

Objections and responses

1. "The young-earth side only wins the questions about what humans are because everyone agrees on them." Not everyone did. The late human revolution, the claims that apes were learning language, the 98.8 percent slogan and the genetic disproof of a first couple were mainstream positions that young-earth writers disputed, and the children find the young-earth writers closer to the data on each. The point is modest, since a model can be right about what without being right about when, but it is real.
2. "Every one of these dates assumes constant rates." The children price the change each clock would need instead of assuming it away. Decay-based dates need decay to run tens to hundreds of times faster after the Flood, later than the accelerated-decay proposal allows. The recombination count needs no calendar at all, because it counts generations directly, and a change in decay rates does not touch it.
3. "Common design explains why humans and chimpanzees are alike." It explains likeness. It does not predict which retroviruses sit at shared positions, why inversions nest as a family tree, or why the differences show the same mix of mutation types that families show today. The young-earth geneticists who say the differences were built in accept the pattern and give no reason for it.
4. "The mainstream story has its own holes." It does, and the children name them: the oldest claimed hominins rest on few, reconstructed bones, the method behind hominin family trees failed its own controlled test, no single steady mutation rate fits every fossil calibration, and nobody knows how human syntax arose. None of these holes shortens a date.

Issues and unanswered questions

1. No young-earth writer has specified one mechanism that moves the radiometric dates, the mutation clocks and the recombination count together by the factors the children report. Until one is proposed and measured, the dates stand against a young chronology.
2. The small-brained mosaic fossils have no settled young-earth placement, and Wood's wider human kind trades the clean gap for coherence.
3. Neither side has explained how human language arose. The gap is a fact; its cause is open.
4. The overview of the dated human records that run through the Flood date, Human History Across the Flood Date, is not yet written.

Verdict

On what humans are, the evidence favours the biblical picture.  The fossils divide, at both ends, into apes and people.  All living people are one shallow family.  Neanderthals and Denisovans were people.  Symbols and burial appear as early as modern human bones, and the language gap between humans and apes is real and unexplained by any gene found so far.  On several of these points young-earth writers were closer to the data than prominent mainstream claims were.

On when, and on how humans relate to the apes, the evidence runs against the young-earth reading.  Fossil, archaeological and genetic clocks that rest on different physics and biology all place human history far beyond any biblical date, from several times for the last Neanderthals to hundreds of times for Lucy's species, and the human-chimpanzee differences carry the marks of descent with known mutation processes.  The best young-earth answers either set the dates aside by the biblical bound or call the pattern created, and neither has been tested.

An honest young-earth position here says three things plainly.  Humans are one family, made distinct, and the data agree.  Several famous arguments against that were overstated and have been withdrawn.  And the dates, the mosaic fossils and the shape of the human-ape likeness are unsolved problems for a young chronology, not settled questions.

Sources