Paleobiota of the Burgess Shale
This is a list of the biota of the Burgess Shale, a Cambrian lagerstätte located in Yoho National Park in Canada.
The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At 508 million years old, it is one of the earliest fossil beds containing soft-part imprints. During the Cambrian, the ecosystem of the Burgess Shale sat under 100 to 300 metres of water at the base of a submarine canyon known as the Cathedral Escarpment, which today is a part of the Canadian Rockies. The ecosystem would have sat in dimly lit water, most likely at the edge, or in the Mesopelagic zone. The ecosystem was preserved by rapid mudslides that quickly buried organisms near, or on the seafloor, which helps explain the rarity of nektonic organisms at the site. The shale would have supported unique environments like brine pools that could have also helped to preserve the fossils. Notable areas that expose the Burgess Shale include the Walcott Quarry, Marble Canyon, Stephen Formation, Tulip Beds, Stanley Glacier, the Trilobite Beds and the Cathedral Formation. With each site occupying a varying depth, and distance from the base of the escarpments.
Arthropoda
Crown-group arthropods and their stem-group relatives are extremely diverse and some species are abundant in the Burgess Shale. Along with their earlier-diverging cousins, the "Lobopodians", they provide great information on early Panarthropod evolution.
Lobopodians
Lobopodians, a grouping of worm-like panarthropods from which arthropods arose, were present in the shale.
Sponges
Sponges were extremely diverse in the shale, with many of them belonging to the class Demospongiae.
Comb-jellies (Ctenophora)
Crown-group and stem-group Ctenophores, also known as comb jellies, are moderately common in the shale, with five genera known from the site.
Hemichordata
Many of the Hemichordates from the shale have either remained enigmatic, or were once classified under other groupings.
Annelida
A number of different Annelid worms are known from the shale.
Priapulida
Various stem-group priapulids are known from the Burgess Shale.
Mollusca
The molluscs of the Burgess shale are diverse in body shapes, the ecological niches they filled, and their enigmatic qualities.
Brachiopods
Many of the brachiopods from the site are members of the class Lingulata.
Cnidaria
A wide variety of cnidarians like scyphozoans and conulariids are known from this site.
Echinodermata
The echinoderms of the shale represent extinct groups distantly related to extant groups.
Chordata
Chordates are very rare in the shale, but the two that are known are possibly being very important in the study of these creatures' earlier evolutions.
Gnathifera
A number of different gnathiferans, including chaetognaths and other groups are known from the Burgess Shale.
Chancellorids
An extinct group of enigmatic sponge-like animals covered in hollow spines
Cyanobacteria
Cyanobacteria are photosynthesizers, and would have been important in the shale.
Red algae are found in the shale, with three genera being known.
This section documents organisms from the shale whose taxonomic affinities are not fully understood, or that do not fit into any of the above groups.