The Apologia

Entropy means evolution can’t happen.

The Anapologia

Invoking the Second Law of Thermodynamics to claim that species can't increase in complexity suffers from a misunderstanding of the Second Law.

Formulations of the 2nd Law involve constraints on it's application expressed in terms like:

“In a closed system…”, “A system and it’s surroundings”, “An isolated system”, “The system and the environment” or a more general observation as Stephen Wolfram puts it "somehow things always tend to get progressively more random”.

The second “law” of thermodynamics is a bit like Occam’s Razor and Hector Barbossa’s view of Pirate Parley. It’s more of a guideline than a rule.

So a population of a particular species is not a closed system. There is input of energy from nutrition ultimately deriving from the sun. There is also Natural Selection, removing some randomness as the system evolves, unlike the case of thermodynamic systems where there is no selective pressure on possible states. With species there is also input of genetic material from other species, usually via viruses which can introduce changes that aren’t entirely random.