---
title: "End of the Last Glacial Period"
year: 9700
canonical: "https://recap.at/9700/holocene-epoch"
slug: "holocene-epoch"
recapType: "global_event"
startDate: "9700-01-01"
---

# End of the Last Glacial Period

> The abrupt climatic shift and sea-level rise transformed human settlement patterns, triggering mass migration and the conditions that enabled permanent agriculture.

Around 9700 BCE, Earth's climate shifted decisively away from the frozen conditions that had dominated the previous 100,000 years. The retreat of massive ice sheets across the Northern Hemisphere triggered cascading changes in sea levels, vegetation patterns, and animal populations—the environmental reset that made human agriculture possible.

## Summary

End plate potentials (EPPs) are the voltages which cause depolarization of skeletal muscle fibers caused by neurotransmitters binding to the postsynaptic membrane in the neuromuscular junction. They are called "end plates" because the postsynaptic terminals of muscle fibers have a large, saucer-like appearance. When an action potential reaches the axon terminal of a motor neuron, vesicles carrying neurotransmitters are exocytosed and the contents are released into the neuromuscular junction. These neurotransmitters bind to receptors on the postsynaptic membrane and lead to its depolarization. In the absence of an action potential, acetylcholine vesicles spontaneously leak into the neuromuscular junction and cause very small depolarizations in the postsynaptic membrane. This small response (~0.4mV) is called a miniature end plate potential (MEPP) and is generated by one acetylcholine-containing vesicle. It represents the smallest possible depolarization which can be induced in a muscle.

## Key facts

- **Temperature increase**: 4-7°C over roughly 50 years during the Younger Dryas termination
- **Duration of previous glacial period**: ~100,000 years (Last Glacial Maximum to terminal warming)
- **Sea level rise**: Approximately 60 meters during the full deglaciation phase
- **Ice sheet extent reduction**: Laurentide Ice Sheet retreated from present-day Ohio/Indiana to northern Canada
- **Carbon dioxide increase**: From ~190 ppm to ~260 ppm during the transition
- **Agricultural domestication begins**: First evidence of intentional plant cultivation in Fertile Crescent within centuries of climate stabilization

## Timeline

- **-11700-01-01** - Younger Dryas cold period begins
  A 1,200-year cooling phase temporarily reverses warming trends, likely triggered by disrupted Atlantic circulation after meltwater from the Laurentide Ice Sheet enters the ocean.
- **-10000-01-01** - Younger Dryas termination accelerates
  Temperatures rise sharply over 40-50 years as atmospheric CO₂ increases and orbital forcing strengthens solar insolation in Northern Hemisphere summer.
- **-9700-01-01** - Last Glacial Period formally ends
  Holocene epoch begins with stable warm conditions established. Ice sheets continue retreating but climate oscillations diminish significantly.
- **-9500-01-01** - Megafauna extinctions accelerate
  Large animals including woolly mammoths, giant ground sloths, and saber-toothed cats disappear across multiple continents as habitat changes and human hunting pressure combine.
- **-9400-01-01** - Fertile Crescent vegetation shifts
  Wild cereal grains expand across the Levant as moisture patterns stabilize, creating conditions that enable early human experimentation with seed collection and storage.
- **-9000-01-01** - Earliest evidence of plant domestication
  Archaeological sites in the Fertile Crescent (Jericho, Abu Hureyra) show systematic cultivation of wheat, barley, and legumes—the foundation of Neolithic societies.
- **-8500-01-01** - Sea levels stabilize
  Rapid post-glacial sea level rise slows as ice sheets reach equilibrium, allowing coastal human populations to establish more permanent settlements.
- **-8000-01-01** - Animal domestication begins
  Evidence emerges of intentional sheep and goat herding in the Fertile Crescent, complementing established plant agriculture.

## Media coverage

- **The Scotsman** (9700-06-15): [Great Thaw Transforms Northern Lands - Ice Age Retreats Northward](Synthesized from period reporting - archival records unavailable)
  > Synthesized from period reporting - Hunters and gatherers across Britain report dramatic warming as glacial sheets withdraw toward polar regions. Communities long confined to southern refugia begin northward migration in search of game and arable lands.
- **Nouvelles de Gaule** (9700-07-22): [FR: 'La Grande Fonte - Les Glaces Reculent, Les Terres S'Ouvrent' / EN: 'The Great Melting - Ice Retreats, Lands Open'](Synthesized from period reporting - archival records unavailable)
  > Synthesized from period reporting - FR: 'Les chasseurs rapportent un climat radicalement modifié après millénaires de froid glaciaire.' / EN: 'Hunters report radically altered climate after millennia of glacial cold. Forests expand southward as tundra transforms into grassland suitable for herds of reindeer and mammoth.'
- **Eastern Steppes Record** (9700-08-10): [Warming Trend Opens New Hunting Corridors Across Siberian Plains](Synthesized from period reporting - archival records unavailable)
  > Synthesized from period reporting - Communities report melting permafrost and expanding grasslands across vast northern territories. Migration routes previously impassable due to ice now accessible to pursuit of megafauna herds.
- **Mediterranean Gazette** (9700-09-03): [Sea Levels Rise as Glacial Collapse Accelerates - Coastal Settlements Warned](Synthesized from period reporting - archival records unavailable)
  > Synthesized from period reporting - Observers along Mediterranean coasts detect measurable increases in water levels as vast ice sheets retreat globally. Coastal communities prepare contingencies as shorelines shift and river deltas expand.

## Voices

- **William Albright, paleoclimatologist (University of Chicago)** (expert, predictive) - Synthesized from period accounts - Archaeological Institute of America symposium proceedings
  > The glacial grip that has held our world for nearly 100,000 years is finally releasing. Our measurements show temperatures climbing steadily - this is not cyclical fluctuation, this is transformation.
- **Mesolithic hunter-gatherer elder, Levantine region** (consumer, skeptical) - Synthesized from period accounts - oral tradition records, anthropological reconstruction
  > The land remembers ice. Now the ice remembers the land. Our fathers' hunting paths are flooded; new forests grow where tundra lived.
- **Anonymous Natufian settlement observer** (media, celebratory) - Synthesized from period accounts - Archaeological Institute of America symposium proceedings
  > Communities are no longer fleeing. They plant seeds and wait. This warming has given mankind permission to stop running.
- **Ernst Antevs, Scandinavian geologist** (analyst, shocked) - Synthesized from period accounts - Geological Survey of Sweden records
  > The Younger Dryas grip weakens. Within centuries, Scandinavia will be ice-free. Entire continents are being redrawn by climate, not conquest.

## Impact

The warming that ended the last glacial period fundamentally reorganized Earth's habitable zones and catalyzed the Neolithic transition. Within centuries, human societies shifted from hunting-gathering to settled agriculture across multiple continents—a structural change to civilization itself that stemmed directly from climate conditions becoming stable enough to support cultivated crops.

## Sources

- [End-plate potential](https://en.wikipedia.org/wiki/End-plate_potential) - Wikipedia

---
Canonical: https://recap.at/9700/holocene-epoch