Our-year-old jonathan is sitting at the lunch counter next to his sister erin. they are having hot dogs for lunch. when his mom cuts jonathan's hot dog into five pieces and erin's into six pieces. jonathan protests, "erin has more than me! " which ability does jonathan not yet demonstrate?

   Conservation

Explanation:  The conservation theory of Swiss scientist Jean Piaget speaks of the ability to logically perceive a certain amount, volume, despite the different shape of a vessel containing a certain liquid, or size despite on how many different parts is divided a particular object, food as in this case. Piaget studied this on children, where he performed experiments and tested children's abilities to see some quantities remain the same even though the shape changes, or some objects remain the same, as far as sizes are concerned, when divided into several parts.

because he had a big bear belly