6th Grade · Science · Activity · shared by Luke Morgan
Explore extremophiles in a volcanic lake with this 6th Grade Science activity. Students analyze clues to identify a mystery organism.
Mystery Investigation: The Phantom of Lake Dallol
Investigation Brief: You are a junior astrobiologist working for the Global Extreme Life Institute. A remote research drone has just returned from Lake Dallol in the Danakil Depression. This lake is one of the most hostile places on Earth: it is highly acidic (pH 0.2) and searing hot. Most incredibly, the drone captured evidence of a microscopic organism living in the burning, acidic puddles.
Your Mission: Analyze the data logs and clues provided to identify the "Phantom" organism. You must determine its classification and explain how it survives in conditions that would dissolve most living cells.
Phase 1: Environmental Data Log
Review the data collected by the drone to understand the "crime scene" where the organism was found.
Environmental Factor
Measurement/Observation
Acidity (pH Level)
pH 0.2 (Highly acidic; similar to battery acid)
Temperature
108 degrees Celsius (Above boiling point of water)
Light Availability
High (Surface lake), but the water is opaque with minerals.
Chemical Presence
High concentrations of iron, sulfur, and magnesium salts.
Phase 2: Evidence Collection
Read the following three clues discovered by the research team. Use these to piece together the identity of the organism.
Clue #1: The Metabolic Trace
The drone detected no oxygen production near the organism. Instead, the area showed a decrease in dissolved iron and sulfur. It appears the organism "eats" minerals and uses the energy stored in chemical bonds to build its own nutrients through a process called chemosynthesis, much like the microbes found near deep-sea hydrothermal vents.
Clue #2: The Protective Barrier
Microscopic scans show the organism has a unique cell membrane made of special fats (lipids) that do not break down in acid. While a human skin…