Chapter 28, Problem 33A

Summary Introduction

To write:

A hypothesis about the decline of amphibian populations in relation to changes in climate.

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

Amphibian populations have been declining worldwide in recent decades. Scientists have been gathering data to determine the potential causes of the fall. Climate change is one of the most significant factors of population loss. Climate change is a global phenomenon that may contribute to an amphibian decline at work. Direct effects of climate change may also be expected, as amphibians are more prone to climate change than other animals. 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. Local environmental changes can reduce the immune function and lead to outbreaks of pathogens and increased mortality or the conditions that change to make pathogen growth more favorable.

Conclusion

Thus, the climatic changes may affect the population in amphibians as they are highly sensitive to the minor variations in temperature and humidity.