About Tiny Sea Simulation

A Scientific Research Platform for Marine Ecosystem Dynamics

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Research Purpose

Tiny Sea Simulation is a scientific research platform developed in collaboration with marine biologist Brian Helmuth to study climate change impacts on marine food webs. The simulation models a 2-tier ecosystem with realistic predator-prey dynamics, thermal adaptation, and sophisticated population mechanics using accumulator systems for accurate tracking of births and deaths.

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Ecosystem Structure

2-Tier Marine Food Web TIER 2: Sheplik (Predators) Arctic Common Tropical Predation TIER 1: Hexapod (Prey) Arctic Common Tropical

6 Marine Species organized in a two-tier food web with three thermal variants optimized for different temperature ranges (Arctic: 5°C, Common: 20°C, Tropical: 35.5°C).

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Temperature Components

Temperature Calculation
T = Base + Seasonal + Climate + Interannual + Daily
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Base Temperature

Starting point (default 20°C)

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Seasonal Variation

Summer/winter cycles

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Climate Warming

Long-term trend (1°C/year)

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Interannual Variation

Year-to-year fluctuations

Daily Variation

Short-term weather patterns

Temperature is bounded between -5°C and 50°C to maintain realistic marine conditions.
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Seven-Step Biology Cycle

Each simulation day follows this precise sequence:

1
Thermal Performance

Calculate using Arrhenius equation

2
Predation

Predators hunt with variable efficiency

3
Final Performance

Thermal × Feeding Rate

4
Thermal Death

If performance < 30% threshold

5
Reproduction

When pop ≥ 2 and perf ≥ 25%

6
Natural Death

Scaled by performance

7
Round Populations & Save Accumulators

Convert to integers and preserve fractional values

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Accumulator Systems

Why We Built This:

Early versions failed when populations became small. A predator with 2 individuals would calculate 0.14 births per day, which rounded to 0 - the species would never reproduce. Similarly, the last creature would calculate 0.02 deaths per day, which rounded to 0 - making it immortal. Accumulator systems solve this by tracking fractional values across days until they accumulate to whole numbers.

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Birth Accumulator

Problem: 0.14 births rounds to 0
Day 1: +0.14 → Total: 0.14 → 0 births
Day 2: +0.14 → Total: 0.28 → 0 births
Day 3: +0.14 → Total: 0.42 → 0 births
Day 4: +0.14 → Total: 0.56 → 0 births
Day 5: +0.14 → Total: 0.70 → 0 births
Day 6: +0.14 → Total: 0.84 → 0 births
Day 7: +0.14 → Total: 0.98 → 0 births
Day 8: +0.14 → Total: 1.12 → 1 birth!

Why: Prevents reproductive failure in small populations. Predators can reproduce even with only 2 individuals.

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Predation Accumulator

Problem: 1 Arctic among 99 Common
Arctic share: 1/100 = 1%
10 prey eaten × 1% = 0.1 Arctic
0.1 rounds to 0 → Arctic never eaten!
...
Day 5: 10 eaten → +0.1 → Total: 0.5
Day 10: 10 eaten → +0.1 → Total: 1.0
1 Arctic eaten (proportional predation works!)

Why: Ensures rare variants are preyed upon proportionally to their abundance, not ignored because of rounding.

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Natural Death Accumulator

Problem: Last creature immortal
Population = 1, Death rate = 2%
1 × 0.02 = 0.02 deaths → rounds to 0
...
With performance scaling:
Poor performance → 5.7% death rate
1 × 0.057 = 0.057 per day
Dies in ~18 days (not immortal!)

Why: Eliminates the "immortal last creature" bug. Even struggling individuals eventually die through accumulated mortality.

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Negative Feedback Mechanisms

Why We Built This:

Without negative feedback, populations explode exponentially and crash catastrophically. Real ecosystems maintain stability through self-regulating mechanisms. We implemented four feedback loops that prevent runaway population growth and create realistic predator-prey oscillations.

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Thermal Performance

Species achieve maximum performance at their optimal temperature and experience reduced efficiency in warmer or cooler conditions. Performance is calculated using Arrhenius equations which accurately model how biological rates change with temperature.

Example: How Temperature Affects Arctic Hexapods
  • At 5°C (optimal temperature): 100% performance ✓ - thriving conditions
  • At 20°C (stressed): 35% performance ⚠ - reduced feeding, slower reproduction
  • At 30°C (extreme stress): 15% performance ✗ - high mortality, population decline
Why Arrhenius Equations:

Simple linear models don't reflect biological reality. Arrhenius equations capture the non-linear nature of biological processes: species tolerate moderate temperature deviations well, but extreme temperatures cause rapid performance collapse. This matches real-world observations of thermal tolerance in marine organisms.