The simplicity of prokaryotic cells prevents them from

Differentiation and specialization.

Explanation:

The prokaryotes are the simplest unicellular organisms that do not posses a well defined nucleus, golgi apparatus, mitochondria and endoplasmic reticulum. The prokaryotes also lack cytoskeleton.

The eukaryotes are more complex in structure than prokaryotes. The eukaryotes have the ability for differentiation and specialization but the prokaryotes are simplest organisms. Thus, the simplicity of prokaryotic cells prevents them from differentiation and specialization.

explanation:

the fossil record extends back to a dog-like ancestor some 55 million years ago, which gave rise to the first horse-like species 55 to 42 million years ago in the genus eohippus.