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- Brachiopod - Wikipedia
Two major categories are traditionally recognized, articulate and inarticulate brachiopods The word "articulate" is used to describe the tooth-and-groove structures of the valve-hinge which is present in the articulate group, and absent from the inarticulate group
- Brachiopods - Examples, Characteristics, Fossils, Pictures
More than 12,000 fossil species have been recognized, with the earliest undisputed brachiopod dating back to the Early Cambrian Period It is believed that inarticulate brachiopods arose first, followed by articulate forms
- Fossil Brachiopods - U. S. National Park Service
Brachiopoda were a dominant group of marine organisms during the Paleozoic Their name comes from the Greek words brachion, meaning “arm,” and podos, meaning “foot ” This references to their internal anatomy Brachiopods were once thought to be mollusks, which have a muscular internal foot
- Brachiopods - British Geological Survey
Brachiopods are virtually defenceless and their shell, enclosing the animal’s organs, is the only protection against predators Most are permanently attached by a fleshy stalk (the pedicle) to a hard, sea-floor surface and are incapable of actively pursuing food
- Brachiopoda - Digital Atlas of Ancient Life
Brachiopods are marine invertebrates, meaning they have no backbone, and are one of the few animal groups that live only in the ocean They live on the ocean bottom in a variety of places, including soft sediments, on rocks, reefs, or in rock crevices where some even anchor themselves with a muscular stalk called a pedicle
- Brachiopods: Ancient Survivors Shed Light on Evolutionary Mysteries . . .
Brachiopod fossils can be found in rocks from the early Cambrian period, which began around 541 million years ago, all the way up to the present day This extensive fossil record provides valuable information about the evolution, diversity, and distribution of brachiopods over time
- Introduction to the Brachiopoda
Depsite their relative obscurity today, brachiopods have a long and rich paleontological history During the Paleozoic era, they were extremely abundant They diversified into a number of different morphologies and even participated in the build-up of ancient reefs
- Generalized Brachiopod Classification - University of Kentucky
Brachiopods are classified into sequentially more specific classes, orders, families, genera, and species, based on shape and features of their shells Brachiopods used to be classified into two broad ranks; inarticulate and articulate, which were then further subdivided
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