they were selectively favoured in such habitats. Not only can seahorses manoeuver exceptionally well in dense seagrass meadows, but the upright seagrass blades would have provided camouflage for their bodies and in that way improved their ability to ambush prey and avoid detection by predators. An alternative explanation for the evolution from pygmy pipehorse to seahorse is based on the finding that a vertically bent head is more efficient in capturing prey because it increases the animal's strike distance, which is considered particularly useful in tail-attached sit-and-wait predators. In that case, the evolution of an upright posture would merely be a means of maximising the angle between head and abdominal axis. There is as yet no fossil evidence for the evolution of seahorses from a pygmy pipehorse ancestor, as the fossil record of both groups is very sparse. The only pygmy pipehorse species of which fossils have been found (Hippotropiscis frenki) lived in the Central Paratethys Sea (the modern-day Tunjice Hills of Slovenia, north of the Mediterranean Sea) during the Middle Miocene, i.e. during a time when seahorses had already evolved. In fact, the oldest known seahorse species, Hippocampus sarmaticus and H. slovenicus, were found at the same site. Independent geological confirmation of the genetic data would require finding a fossil site from the Oligocene in which seahorse-like pygmy pipehorses are present, but seahorses are not. Given the fact that Idiotropiscis is endemic to temperate Australia and the most basal seahorse lineages occur in Australia and the tropical West Pacific, these regions are the most likely candidates for such a site. References External links Pictures: Ancient pygmy pipehorse species found National Geographic, 8 May 2012. How seahorses evolved to swim "standing up" National Geographic News, 22 May 2009 How the seahorse got its shape Nature Video, 21 January 2011 Sydney's pygmy pipehorse Australian Museum 14 September 2012 Wakatobi pygmy pipehorse Wakatobi Dive Resort Syngnathidae Fish subfamilies Taxa named by Charles Lucien Bonaparte