When I envisaged this post last night, I was simply going to make it an easy, simple little table of the L haplogroup variants on my Y Chromosome. I had a few problems with that, and therefore consulted for a while with Google Gemini AI. Before I knew it, my post grew and grew. I know that I have a particular kind of mind. One that hyper-focuses, sees patterns in data, and buries itself into whatever science, history, or nature that currently catches my attention. As this blog is intended only for me to enjoy making my observations, I shouldn't be apologizing.
Gemini helped me a little with organising the dating, and contexts of the yDNA. When I was happy with it, I then felt that the beginning of the story was far older than yDNA Adam, and therefore I asked it to add some information on earlier human evolution. But then that wasn't enough, because humans are only the recent end of just one lineage of life, so I asked it to add the story of Life on Earth. But then I knew that wasn't enough. You see, we are star dust. We see ourselves as selves. As individuals that matter the most. We make our own ego. Yet all life is entwined, and interdependent. Every several years, every cell in our body is replaced. Even as an individual I am no more than a chain of events, a process rather than a thing. A small percentage of my bodyweight isn't even the same species - it belongs to countless micro-organisms of a biome. We are also a lichen,
We interbeing not only with life, but with the universe. The matter in the fingers that punch this keyboard have been a part of other lifeforms before me. My existence has consequence for everything. Enough of the profound thoughts, let me get this list of my process down:
Part 1. The Cosmic Dawn: From Big Bang to Earth
The Big Bang (Birth of the Universe)
Age: c.\ 13.8 Billion Years Ago
Context: Infinitely dense and hot energy expands aggressively. In mere fractions of a second, the universe grows from smaller than an atom to massive proportions.The Cosmic Dark Ages & The First Stars
- Age: c.\ 13.6 Billion Years Ago
Context: After the initial flash, the universe goes pitch black for millions of years. Eventually, gravity pulls hydrogen and helium gas together, igniting the very first stars and flooding the universe with light. The "Cooking" of the Elements
- Age: c.\ 13.2 to 5.7 Billion Years Ago
Context: Generations of massive stars live and die. Inside their burning cores, they fuse simple hydrogen into carbon, nitrogen, oxygen, and iron. When they die in violent supernova explosions, they blast this "stardust" out into the void. Formation of the Milky Way & Solar System
- Age: c.\ 4.6 Billion Years Ago
Context: A massive cloud of floating stardust and gas collapses under its own gravity. At the center, our Sun ignites. The leftover swirling debris clumps together to form the planets, including Earth. The Young, Violent Earth
- Age: c.\ 4.3 to 4.5 Billion Years Ago
Context: Earth is a molten ball of fire. A Mars-sized planet slams into it, blasting debris into space that becomes our Moon. As the planet cools, water vapor condenses to form the first oceans.
Part 2: The Spark of Life to Early Animals
Hypothesis 1: The "Warm Little Pond" (Primordial Soup)
Age: c. 4 to 4.2 Billion Years Ago
Context: Pioneered by Oparin and Haldane, and later tested by the famous Miller-Urey experiment. This theory suggests that lightning or solar radiation struck shallow tidal pools filled with simple chemicals, sparking the formation of amino acids and the building blocks of life.
Hypothesis 2: Deep-Sea Hydrothermal Vents ("Iron-Sulphur World")
Age: c. 4 to 4.2 Billion Years Ago
Context: Many scientists now believe life didn't start at the sunny surface, but in the pitch black of the deep ocean floor. Alkaline hydrothermal vents provided the perfect combination of heat, continuous chemical flow, and microscopic rock pockets that acted as the world's first "cell membranes."
Hypothesis 3: The RNA World
Age: c. 3.8 to 4 Billion Years Ago
Context: In modern life, DNA holds the instructions, but proteins do all the work. It's a classic chicken-and-egg problem. This hypothesis suggests that RNA—which can both store information and cause chemical reactions—was the original master molecule that predated both DNA and proteins.
The LUCA (Last Universal Common Ancestor)
Age: c. 3.8 Billion Years Ago
Context: Not the first living thing, but the single-celled organism from which all bacteria, trees, animals, and humans ultimately descend. It already used DNA and the same genetic code we use today!
The Great Oxidation Event (The Oxygen Catastrophe)
Age: c. 2.4 Billion Years Ago
Context: Early Earth had almost no free oxygen. Then, a group of bacteria (cyanobacteria) developed photosynthesis and started dumping oxygen into the atmosphere as a waste product. This wiped out most anaerobic life on Earth but paved the way for complex, oxygen-breathing organisms.
The First Complex Cells (Eukaryotes)
Age: c. 1.8 Billion Years Ago
Context: Simple bacterial life trades in its simple structure for complexity. Cells develop a protected nucleus to hold DNA and absorb the free-living bacteria that become mitochondria (the cell's power plants), giving cells the massive energy boost needed to become multi-cellular.
Part 3: The Deep Time Journey to Humanity
The Dawn of Animals (Early Metazoans)
Age: c. 750 Million Years Ago
Context: Single-celled organisms begin clumping together to form the very first multi-cellular animals.
The "Cambrian Explosion" (The Bilaterians)
Age: c. 530 Million Years Ago
Context: A massive burst of evolutionary creativity. Creatures develop bilateral symmetry (a distinct front, back, left, and right side) and the first true eyes, shells, and nervous systems appear in the oceans.
Life Walks on Land (Tetrapods)
Age: c. 380 Million Years Ago
Context: Fish with strong, lobe-like fins begin adapting to breathing air and hauling themselves out of the water, becoming the ancestors of all land-dwelling vertebrates.
The Mammal-Like Reptiles (Synapsids)
Age: c. 310 Million Years Ago
Context: Long before the famous dinosaurs, a group of reptiles branches off. They begin developing larger brains, specialized teeth, and a more upright posture—setting the stage for true mammals.
The First True Mammals
Age: c. 210 Million Years Ago
Context: Living in the literal shadows of the dinosaurs, tiny shrew-like creatures emerge. They are warm-blooded, have fur, and produce milk to feed their young.
The Dawn of the Y Chromosome
Age: c. 180 Million Years Ago
Context: A normal chromosome in early mammals mutates to hold the SRY gene, creating the very first Y chromosome and starting the paternal line we track today.
The Asteroid & The Rise of Primates
Age: c. 66 Million Years Ago
Context: A massive asteroid impacts Earth, wiping out the non-avian dinosaurs. With the giant reptiles gone, small tree-dwelling mammals flourish, leading quickly to the first true primates.
The Great Apes (Hominidae)
Age: c. 15 to 20 Million Years Ago
Context: Primates in Africa branch off into a group of large, tailless primates with larger brains and complex social structures. This group includes the ancestors of gorillas, orangutans, humans, and chimpanzees.
The Split with Pan (Chimpanzees)
Age: c. 6.2 Million Years Ago
Context: Our lineage officially separates from the ancestors of chimpanzees and bonobos. These early hominins began moving out of the dense forests.
The Dawn of Bipedalism (Australopithecus)
Age: c. 4 Million Years Ago
Context: Early human ancestors like the famous "Lucy" fossil are walking upright on two legs full-time, freeing up hands for carrying things and early tool use.
The First of the Genus Homo (Homo habilis)
Age: c. 2.4 Million Years Ago
Context: The "Handy Man" emerges. Brain sizes increase significantly, and the intentional crafting of stone tools becomes a primary survival strategy.
Mastery of Fire & Global Travel (Homo erectus)
Age: c. 1.9 Million Years Ago
Context: Body proportions become just like modern humans. They master fire, adapt to cooking food, and become the first human ancestors to expand out of Africa into Asia and Europe.
The Common Ancestor with Neanderthals (Homo heidelbergensis)
Age: c. 600,000 Years Ago
Context: A large-brained human ancestor that lived in both Africa and Europe. The European populations eventually evolved into Neanderthals, while the African populations led to us.
Anatomically Modern Humans Emerge (Homo sapiens)
Age: c. 300,000 Years Ago
Context: Humans who look physically identical to us today are now walking the earth in Africa.
The "Y-Chromosomal Aaron" (Root of all Y-DNA)
Age: c. 230,000 to 270,000 Years Ago
Context: This is the theoretical single male in Africa who passed down the Y-chromosome that all living men carry today.
Part 4: Paternal Lineage & TMRCA Timeline
yDNA Variants
A01
Age: 125,500 YBP (c. 123,550 BCE)
Context: Africa. The root of all human paternal lines.
F
Age: 42,500 YBP (c. 40,550 BCE)
Context: Southwest Asia. Parent of most non-African lines.
LT
Age: 37,050 YBP (c. 35,100 BCE)
Context: West Asia. Paleolithic hunter-gatherers.
L / M20
Age: 20,100 YBP (18,150 BCE)
Context: Caucasus to Iranian Plateau. In Ice Age refuges of West Asia. The birth of the L super-clade. LGM Ice Age Hunter-gatherers.
M317
Age: 11,050 YBP (9,100 BCE)
Context: Eastern Fertile Crescent. Controlling wild herds of ibex, mouflon. Gathering wild cereals.
SK1412
Age: 10,050 YBP (8,050 BCE)
Context: Zagros (Iran) foothills and valleys. Early Neolithic Farmer population herding and cultivating cereals.
FGC51074 / SK1414
Age: 7,800 YBP (5,880 BCE)
Context: Branching out to Anatolia, Caucasus, Near East, Iranian Plain, Gedrosia, and Indus Valley, but my specific line possibly remained in the Zagros region.
FGC51041
Age: 7,130 YBP (5,180 BCE)
Context: Early Copper Age expansion. If still in Zagros region, likely in contact with Elamite, Indus Valley, and Sumerian civilizations. Exploiting soils of floodplains for agriculture
FGC51040
Age: 6,000 YBP (4,050 BCE)
Context: West Asia. Continued Copper Age movements. Possible link to Assyrians, Hurrians and Mittani dispersals.
FGC51036
Age: 3,130 YBP (c. 1,180 BCE)
Context: End of Bronze Age. Anatolia, Levant or Mediterranean. Greek world?
Arrival in England
Age: 600 YBP (c. 1350–1400 CE)
Context: Late Medieval period; potential entry into Britain. Most likely through the port of Southampton. Suspect Genoese or Venetian galleys. My yDNA ancestor may have been recruited as a crewman from the Levant.
Brooker / Chandler split
Age: 400 YBP (c. 1550–1600 CE)
Context: England. Tudor era. Surnames become solidly fixed. Suspect that the surname split between Chandler and Brooker occurred around the area of Basingstoke, Sherfield Upon Loddon, or Kingsclere in Hampshire, England.
Recorded genealogy
Age: 277 years ago (1749 CE)
Context: Clear paper records begin. My 6x great-grandfather, John Brooker, married Ann Gardiner at Oxford College while residing at Long Wittenham, Berkshire, England. Copyhold farmer on open fields held by St Johns college, Oxford.
Relocation to Oxfordshire
Age: 211 years ago (1815 CE)
Context: My 4x great-grandfather John Brooker takes the yDNA from Long Wittenham to the Rotherfield Peppard, Shiplake, Harpsden, and Henley areas of Oxfordshire. Agricultural labourer.
Relocation to London
Age: 144 years ago (1883 CE)
Context: My 2x great-grandfather Henry Brooker takes the yDNA from Harpsden, Oxfordshire to Fulham, Bethnal Green, Deptford, and then Lewisham, London. Cart driver.
Relocation to Norfolk
Age: 120 years ago (1906 CE)
Context: The yDNA is taken to Norfolk with my grandfather Reginald John Brooker. Labourer.
My Birth
Age: 60+ years ago
Context: I am born.
The DNA Test
Age: 10 years ago (2016 CE)
Context: I took a DNA test and discovered my terminal yDNA branch was L-FGC51036, linking our personal story back through the thousands of generations listed above!
