Mollusk - Evolution, Paleontology, Gastropods | Britannica
2024年11月11日 · The fossil record gives little clue about the origin of mollusks and how the classes differentiated in Precambrian times. Phylum Mollusca has about 50,000 species in the …
Mollusk Facts: Habitat, Behavior, Diet - ThoughtCo
2019年12月13日 · Examining the fossil evidence, paleontologists have established the existence of two now-extinct classes of mollusk. "Rostroconchians" lived in the world's oceans from …
The Mollusca - University of California Museum of Paleontology
Mollusca is one of the most diverse groups of animals on the planet, with at least 50,000 living species (and more likely around 200,000). It includes such familiar organisms as snails, …
Fossil Record of Gastropoda - Digital Atlas of Ancient Life
Gastropods have left behind an extraordinary fossil record that documents a rich evolutionary history. They are distinctive among animals for their high taxonomic, ecological, and …
Mollusca - Wikipedia
Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. They are highly diverse, not just in size and anatomical structure, but also in …
Evolution of molluscs - Wikipedia
The evolution of the molluscs is the way in which the Mollusca, one of the largest groups of invertebrate animals, evolved. This phylum includes gastropods, bivalves, scaphopods, …
Mollusk | Definition, Characteristics, Shell, Classification, & Facts ...
2024年11月11日 · Mollusk, any soft-bodied invertebrate of the phylum Mollusca, usually wholly or partly enclosed in a calcium carbonate shell secreted by a soft mantle covering the body. …
Half a billion-year-old spiny slug reveals the origins of molluscs
2024年8月2日 · A team of researchers including scientists from the University of Oxford have made an astonishing discovery of a new species of mollusc that lived 500 million years ago. …
Living Fossils: Mollusks - Digital Atlas of Ancient Life
Mollusks are a group of animals without back bones (invertebrates) that have an unsegmented body, often covered by a shell (exceptions include octopuses and squid). Mollusk shells are …
Class Bivalvia - Digital Atlas of Ancient Life
Bivalves (also known as “pelecypods” or, in older literature, “lamellibranchs”) are a very diverse and abundant group of mollusks. They live today throughout the world’s oceans and fresh …