Complex sentence: The meaning of "degeneration" was poorly defined but can be described as an organism's change from a more complex to a simpler, less differentiated form and in this respect, it is similar to 19th century conceptions of biological devolution.
Split into simpler sentences: The meaning of "degeneration" was poorly defined but can be described as an organism's change from a more complex to a simpler, less differentiated form. In this respect, it is similar to 19th century conceptions of biological devolution.