Phanerozoic/Cambrian period

Kenneth Sobieski This page is under construction

General
The Cambrian Period, named for a sparsly fossiliferous sequence of rocks in Wales(Latin name: Cambria) occurred between 542 Million Years Ago (MYA) and 488 MYA. The system was named by Adam Sedgwick, a Geology professor at Cambridge University, in the 1830s.

Climate
The Cambrian world was bracketed between two ice ages, one during the late Late Proterozoic and the other during the Ordovician. During these ice ages, the decrease in global temperature led to mass extinctions. Cooler conditions eliminated many warm water species, and glaciation lowered global sea level. However, during the Cambrian there was no significant ice formation. None of the continents were located at the poles, and so land temperatures remained mild. In fact, global climate was probably warmer and more unifrom than it is today. With the beginning of the Cambrian at the retreat of Proterozoic ice, the sea level rose significantly. Lowland areas such as Baltica were flooded and much of the world was covered by epeiric seas. This event opened up new habitats where marine invertebrates, such as the trilobites, radiated and flourished.

Land Mass Configuration
Breakup of Rodinia into:
 * Gondwana (today's southern continents)
 * Laurentia (most of North America)
 * Siberia
 * Baltica

Intra-Cambrian Periods
Russian-Kazakhian Stages
 * Batyrbayan 		(491.5 - 488)
 * Aksayan 		(493 - 491.5)
 * Sakian 			(494.5 - 493)
 * Ayusokkanian 		(501 - 494.5)
 * Mayan 			(502-501)
 * Amgan 			(513 - 502)
 * Toyonian		(518.5 - 513)
 * Botomian 		(524 - 518.5)
 * Atdabanian 		(530 - 524)
 * Tommotian 		(534 - 530)
 * Nemakit-Daldynian 	(542 - 534)

Regional Stages
 * Dolgellian 		(492.5 - 488)
 * Festiniogian 		(496.8 - 492.5)
 * Maentwrogian 		(501 - 496.8)
 * Lenian			(524 - 513)

North American Stages
 * Sunwaptan 		(493MYA To 491MYA)
 * Steptoan		(494.5MYA To 493MYA)
 * Marjuman 		(504 To 494.5 Ma)
 * Delamaran 		(512MYA To 504MYA)
 * Dyeran 			(524.5MYA To 512MYA)
 * Montezuman 		(529.5MYA To 524.5MYA)

Australian Stages
 * Payntonian  		(491 - 488)
 * Idamean 		(497 - 494)
 * Mindyallan 		(501-497)
 * Boomerangian 		(504-501)
 * Undillian 		(506-504)
 * Florian 		(508-506)
 * Templetonian 		(510-508)
 * Ordian     		(520 - 510)

Chinese Stages
 * Zhungxian      	(505 - 501)
 * Zuzhuangian 		(509-505)
 * Maozhangian 		(513 - 509)
 * Longwangmioan 		(518-513)
 * Changlangpuan 		(523-518)
 * Qungzusian     	(532 - 523)
 * Meishuchuan 		(542 +/- 0.3 To 532 Ma)

Stratigraphy
On of the most famous stratigraphic formations is the Burgess Shale in what is now British Columbia's Yoho National Park, in an area of the Canadian Rocky Mountains known as the Burgess Pass.

Flora and Fauna: The Cambrian Explosion
With the breakup of Rodinia, and the melting of glaciers, the world gained much more warm, shallow, oxygen-rich coastlines which life could exploit. The favorable climate lead to what is popularly known as "The Cambrian Explosion." The Cambrian Explosion seems, in fact, to have been an "arms race" between the predators and the prey, which may also help to explain the diversity. Land Animals Sea Animals Land Plants Sea Plants
 * NONE
 * Invertibrates
 * Aysheaia pedunculata
 * Hallucigenia
 * Anomalocaris
 * Opabinia
 * Wiwaxia
 * Arthropods
 * trilobites
 * most abundant and diverse animals of Cambrian time
 * long antennae, compound eyes, many jointed legs, and a hard exoskeleton
 * ranged from a few millimeters (1 mm = 0.25 inches) to 45 centimeters (18 inches).
 * archaeocyathids
 * hyoliths
 * monoplacophorans
 * inarticulate brachiopods
 * primitive echinoderms
 * articulate brachiopods
 * stony and lacy bryozoans
 * stromatoporoids
 * cephalopods
 * crinoids and blastoids
 * starfish
 * graptolites
 * bivalves
 * gastropods
 * vertebrates
 * echinoids
 * crustaceans
 * gymnolaemate bryozoans
 * Vertibrates
 * Haikouichthys
 * NONE
 * Single-Celled
 * Algaes
 * Fungi (molds, mushrooms, and yeasts)
 * lichens (cooperation between fungi and algae to form a single-organism partnership)
 * mosses
 * Multi-Celled
 * None