Broadly speaking, the human brain is a collection of software hacks compiled into a single, somehow-functional unit. Each “feature” was added as a random mutation that solved some specific problem to increase our odds of survival. In short, the human brain is a mess. Everything about evolution is messy. So, I assume Eridians are also a mess of random mutations. But whatever led to their brains being how they are, it gave them what we humans would call “photographic memory.”
