Myth 69: “Chameleons Will Die When Temperatures Drop to the 40s (°F)”

Reality: No, They Will Not.

Most chameleon species inhabit regions where temperatures occasionally or regularly drop to, or even below, the freezing point—and they have survived under these conditions for millions of years.

Even well-known species demonstrate this resilience:

• Yemen chameleons (Chamaeleo calyptratus): native to elevations from 1,230 to 2,800 meters above sea level

• Panther chameleons (Furcifer pardalis): some populations exceed 1,000 meters altitude

• Jackson's chameleons (Trioceros jacksonii): found between 1,200 and 2,200 meters above sea level

These species routinely experience nighttime temperatures in the range of 5°C (41°F) or lower.

Cold Is Not the Lethal Factor

Chameleons are heterothermic animals. When temperatures drop, they simply reduce their metabolic rate.

Most species can survive short-term exposure to temperatures 2–4°C below freezing (28–25°F) without fatal consequences.

What Kills Them Is Freezing Water

Water comprises over 90% of their body mass, distributed throughout tissues and cells.

This water is not pure—it contains salts at roughly 0.9% concentration, equivalent to one teaspoon of salt per liter, similar to blood plasma.

• Pure water freezes at 0°C (32°F)

• Salt-containing water freezes at slightly lower temperatures: –2°C to –4°C (28°F to 25°F)

Even this saline water will eventually freeze.

The danger is not the freezing itself—but autolysis.

Autolysis Explained

When water freezes, it forms sharp-edged ice crystals. These crystals rupture cell membranes.

Upon thawing, intracellular fluids leak out, leading to irreversible tissue damage and death.

Some animals (e.g., certain frogs and nematodes) produce compounds that prevent sharp crystal formation, allowing homogeneous freezing.

These species can survive deep freezing and resume metabolic function upon thawing.

Chameleons do not possess these compounds.

If their tissues freeze, they die.

However, Before Freezing Occurs… They Can Still Function

Species such as Trioceros schubotzi, T. nyirit, and some populations of T. hoehnelii experience near-freezing temperatures almost daily.

At 5°C (41°F), they remain active—capable of tongue projection and feeding.

Conclusion

• Chameleons do not die when temperatures drop to the 40s (°F)
  
• They are biologically equipped to survive cold
  
• The true threat is freezing water and cellular rupture, not ambient temperature alone