Sea horses (Hippocampus sp.) generally cling onto plants with their tails, and swim upright with their dorsal fin because they lack tail fins. Their ability to swim upright is based on their being able to fill their flotation sacs with air very quickly. Pictured is a fossilized sea horse discovered in rock beds in northern Italy. This sea horse, from Miocene period, is exactly the same in terms of all its organs and structures—its skeleton, flotation sac and gills—as present-day sea horses. Sea horses have remained unchanged since they first begin appearing in the fossil record, and fundamentally invalidate evolutionist claims.