Ellie’s dad tells her that his fingers used to wrinkle up when he went swimming

Lake Michigan is a freshwater lake with lower osmolarity than human tissue (i.e., It is hypotonic to the water in human tissue). Ocean water is close to isotonic with human tissue. Hence, there will be a net movement of water into human tissue from Lake Michigan water but not from ocean water. Great Salt Lake has a high concentration of dissolved particles. Hence, if there is any net movement of water, it will be out of the skin rather than into the skin. There will be no wrinkling or swelling. Skin may feel tight and dry and might crack after leaving the lake.

Thanks, perfect response.