Chapter 28, Problem 32A

Summary Introduction

To write:

The relationship between water depth during development and survival rate of embryos.

Introduction:

Amphibians include toads, frogs, salamanders, newts, and legless caecilians. Most amphibians are distinguished by moist skin without scales, four legs, exchange of gases through skin, a circulatory system with double loop, lungs, and aquatic larvae.

Explanation of Solution

Amphibians are highly prone to minor variations in temperature and humidity due to their permeable skin, biphasic lifecycles and unshelled eggs. Climate changes leading to a decreased amount of rainfall have an effect on the developing amphibian's eggs in shallow pond water. If the water depth is decreased, the eggs are exposed to more ultraviolet light. Increased sensitivity of UV light leads to an increased risk of fungal infection in amphibian eggs.

Conclusion

Thus, the water depth can affect the survival rate of embryos in amphibians. If the water depth increases, the eggs are safe from UV light.