Ammonite Fossils in the Philippines
Gone, but never forgotten.
This sea dweller disappeared almost at the same time when dinosaurs went extinct.
For today’s Discover Geology, the National Museum Bicol features fossils of an extinct squid-like sea creature from Bicol— the shelled cephalopods called ammonites.
Ammonites were predatory marine animals from the Class Cephalopoda having shells like nautilus, but squids, octopus, and cuttlefishes are their closest relative. Its shell is coiled with chambers divided by walls called septa, which help strengthen the shell and stop it from being crushed by external water pressure.
These squid-like sea creatures used to live in warm to temperate shallow saltwater environments. They came in different sizes and shapes: some were smaller than an inch to as large that can reach nine feet wide.
When did ammonites exactly vanish? These creatures lived during the Jurassic Period (201 million years ago) and became extinct at the end of the Cretaceous Period (66 million years ago). They were buried in sediments million years ago and became fossils in the long run.
Did you know that we have ammonite fossils in the Philippines? One of the sites where we discovered these include the Silungan ng Higante (Giant’s Haven) in San Andres, Catanduanes. These fossils from Catanduanes are estimated to be Aptian-Albian age (about 125–100.5 million years ago).
Though extinct, ammonite shells serve as “index fossils” to help our geologists date and identify the age of other fossils and rock formations.
If you are amazed by our latest heritage trivia, please visit our Geological Exhibit at the #NationalMuseum Bicol when we re-open to closely examine the replicas of these fossils from Silungan ng Higante in San Andres, Catanduanes.
You may want to read: