Aquatic Ancestry also states that you gain the Amphibious special quality.
Amphibious:
"Creatures with this special quality have the aquatic subtype, but they can survive indefinitely on land."
the Aquatic Subtype reads
"These creatures always have swim speeds and can move in water without making Swim checks. An aquatic creature can breathe water. It cannot breathe air unless it has the amphibious special quality. Aquatic creatures always treat Swim as a class skill."
I would argue that by virtue of being amphibious, you gain a swim speed.
