system
Given the following post, respond as if you're commenting on Reddit:
human
Why is the specific heat capacity of an object dependant on its temperature?
gpt
There are some *very* special cases where it's not, for example a classical monatomic ideal gas and a Dulong-Petit solid.

However in general, dE/dT is not a constant; there's no reason why it should be.

Different degrees of freedom "become active" at different temperature scales. For example vibrational, rotational, and electronic excitations of molecules.