The Department of Invertebrate Zoology was established in the California Academy or Sciences in 1914, and was combined with the Department of Geology in 1982. Our curators do research on Recent invertebrates, fossils, diatoms, and minerals. Over 2 million research specimens are maintained in our wet and dry collections.

Coral Reefs

Coral reefs are located in shallow waters of tropical and subtropical regions - which provide marine waters, warm temperatures and sunlight.  The organisms that build coral reefs are corals that house algal symbionts within their tissues.


The Echinodermata is a phylum of exclusively marine invertebrates with a fossil record extending back to the Precambrian.


The Opisthobranchia is a group of largely marine mollusks, the “sea slugs” - shelled slugs, sea hares, the pelagic pteropods, side-gilled slugs, and the nudibranchs – an extremely diverse group of gastropod mollusks.  The IZG department currently houses perhaps the world’s best opisthobranch collections of international scope.


Octocorallian coel-

enterates include some of the most beautiful and morphologically diverse animals in the oceans - the soft corals, sea fans, and sea pens. They are a group of corals characterized by eight feathery tentacles surrounding the mouth of each polyp.


Onychophora is a small group of very primitive arthropods that are interesting to evolutionary biologists for that very reason.


The CAS Diatom Collection web site is an ongoing project to present taxonomic information, images, records of collections, and references pertaining to diatoms. This work has been supported in part by grants BSR-9017609 and DEB-9505269 from the National Science Foundation.


Geology is the study of the Earth - a multidisciplinary science where earth scientists use aspects of physics, chemistry, biology and other fields to study earth history, materials, structure, and the processes that act upon the earth. Traditionally, geology is more of a field oriented science rather than a laboratory one, and remains that way today.  Rocks, minerals, and fossils make up substantial parts of our research and collections in the Academy’s IZG department.

Paleontology Laboratory

The Roopnarine Paleontology Lab is housed in the Department of Invertebrate Zoology and Geology. The department also houses the invertebrate and vertebrate fossil collections, the paleobotanical collection, the micropaleontology collections, and the gem and mineral collections.