* Abstract Nouns: These represent ideas, qualities, or concepts that you can't physically touch. Examples include: love, freedom, happiness, courage.
* Concrete Nouns: These represent things you can physically touch or perceive with your senses. Examples include: dancer, rattlesnake, shoulders.
In the sentence, "The dancer picked up a rattlesnake and draped it over his shoulders," all the nouns are concrete:
* Dancer: A person who dances.
* Rattlesnake: A type of snake.
* Shoulders: Body parts.
Therefore, the sentence doesn't contain an abstract noun.